[hamradio-commits] [soapyaudio] 01/02: Imported Upstream version 0~git20160607

Andreas E. Bombe aeb at moszumanska.debian.org
Thu Aug 25 01:25:32 UTC 2016


This is an automated email from the git hooks/post-receive script.

aeb pushed a commit to branch master
in repository soapyaudio.

commit 57702b030bdf02cf1278caa51fce9aa1dc522a8d
Author: Andreas Bombe <aeb at debian.org>
Date:   Wed Aug 24 21:57:41 2016 +0200

    Imported Upstream version 0~git20160607
---
 .gitignore                              |     1 +
 CMakeLists.txt                          |   158 +
 Findhamlib.cmake                        |    59 +
 LICENSE.txt                             |    21 +
 LibFindMacros.cmake                     |    99 +
 README.md                               |    11 +
 Registation.cpp                         |   112 +
 RigThread.cpp                           |   101 +
 RigThread.h                             |    49 +
 RtAudio/FunctionDiscoveryKeys_devpkey.h |   212 +
 RtAudio/RtAudio.cpp                     | 10229 ++++++++++++++++++++++++++++++
 RtAudio/RtAudio.h                       |  1163 ++++
 RtAudio/readme                          |    61 +
 Settings.cpp                            |   603 ++
 SoapyAudio.hpp                          |   275 +
 Streaming.cpp                           |   678 ++
 debian/changelog                        |     5 +
 debian/compat                           |     1 +
 debian/control                          |    22 +
 debian/copyright                        |    50 +
 debian/docs                             |     1 +
 debian/rules                            |    20 +
 debian/source/format                    |     1 +
 23 files changed, 13932 insertions(+)

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..378eac2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+build
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..66b1cdb
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,158 @@
+########################################################################
+# Build Soapy SDR support module for Audio Devices
+########################################################################
+cmake_minimum_required(VERSION 2.8.7)
+project(SoapyAudio CXX)
+
+find_package(SoapySDR "0.4.0" NO_MODULE REQUIRED)
+if (NOT SoapySDR_FOUND)
+    message(FATAL_ERROR "Soapy SDR development files not found...")
+endif ()
+
+list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR})
+
+option(USE_HAMLIB OFF "Support hamlib for radio control functions.")
+
+if (USE_HAMLIB)
+    find_package(hamlib REQUIRED)
+    
+    if (NOT hamlib_FOUND)
+        message(FATAL_ERROR "hamlib development files not found...")
+    endif ()
+    
+    include_directories(${hamlib_INCLUDE_DIRS})
+    if (${hamlib_STATIC_FOUND})
+        link_libraries(${hamlib_STATIC_LIBRARIES})
+    else()
+        link_libraries(${hamlib_LIBRARIES})
+    endif()
+
+	ADD_DEFINITIONS(-DUSE_HAMLIB)	    
+endif ()
+
+# list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR})
+
+include_directories(${CMAKE_CURRENT_SOURCE_DIR})
+include_directories(${CMAKE_CURRENT_SOURCE_DIR}/RtAudio)
+
+#enable c++11 features
+if(CMAKE_COMPILER_IS_GNUCXX)
+
+    #C++11 is a required language feature for this project
+    include(CheckCXXCompilerFlag)
+    CHECK_CXX_COMPILER_FLAG("-std=c++11" HAS_STD_CXX11)
+    if(HAS_STD_CXX11)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+    else(HAS_STD_CXX11)
+        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
+    endif()
+
+    #Thread support enabled (not the same as -lpthread)
+    list(APPEND AUDIO_LIBS -pthread)
+
+    #disable warnings for unused parameters
+    add_definitions(-Wno-unused-parameter)
+
+endif(CMAKE_COMPILER_IS_GNUCXX)
+
+if (APPLE)
+   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Wc++11-extensions")
+endif(APPLE)
+
+IF (WIN32)
+	set(USE_AUDIO_DS ON CACHE BOOL "Support DirectSound Audio")
+	set(USE_AUDIO_WASAPI OFF CACHE BOOL "Support WASAPI Audio")
+	# TODO:
+	# set(USE_AUDIO_ASIO OFF CACHE BOOL "Include support for ASIO Audio")
+
+	# WASAPI
+	IF(USE_AUDIO_WASAPI)
+		ADD_DEFINITIONS(-D__WINDOWS_WASAPI__)	
+		IF (NOT MSVC)	
+			SET(AUDIO_LIBS ${AUDIO_LIBS} -luuid -lksuser)
+		ENDIF(NOT MSVC)
+	ENDIF(USE_AUDIO_WASAPI)
+
+	# DirectSound
+	IF (USE_AUDIO_DS)	
+		ADD_DEFINITIONS(-D__WINDOWS_DS__)	
+		IF (MSVC)	
+			SET(AUDIO_LIBS ${AUDIO_LIBS} dsound.lib)
+		ELSE (MSVC)
+			SET(AUDIO_LIBS ${AUDIO_LIBS} -ldsound)
+		ENDIF (MSVC)
+	ENDIF(USE_AUDIO_DS)    
+ENDIF (WIN32)
+
+IF (UNIX AND NOT APPLE)
+    SET(USE_AUDIO_PULSE ON CACHE BOOL "Support Pulse Audio")
+    SET(USE_AUDIO_JACK OFF CACHE BOOL "Support Jack Audio")
+    SET(USE_AUDIO_ALSA OFF CACHE BOOL "Support ALSA Audio")
+    SET(USE_AUDIO_OSS OFF CACHE BOOL "Support OSS Audio")
+  
+    IF(USE_AUDIO_PULSE)
+       SET (AUDIO_LIBS ${AUDIO_LIBS} pulse-simple pulse)
+       ADD_DEFINITIONS(
+            -D__LINUX_PULSE__
+       )
+    ENDIF(USE_AUDIO_PULSE)
+
+    IF(USE_AUDIO_JACK)
+       find_package(Jack)
+       SET (AUDIO_LIBS ${AUDIO_LIBS} ${JACK_LIBRARIES})
+       ADD_DEFINITIONS(
+            -D__UNIX_JACK__
+       )
+       include_directories(${JACK_INCLUDE_DIRS})
+    ENDIF(USE_AUDIO_JACK)
+
+    IF(USE_AUDIO_ALSA)
+       SET (AUDIO_LIBS ${AUDIO_LIBS} asound)
+       set(ALSA_INCLUDE_DIR "/usr/include" CACHE FILEPATH "ALSA include path")
+       include_directories(${ALSA_INCLUDE_DIR})
+       set(ALSA_LIB_DIR "/usr/lib" CACHE FILEPATH "ALSA lib path")
+       link_directories(${ALSA_LIB_DIR})
+       ADD_DEFINITIONS(
+           -D__LINUX_ALSA__
+       )
+    ENDIF(USE_AUDIO_ALSA)
+
+    IF(USE_AUDIO_OSS)
+       SET (AUDIO_LIBS ${AUDIO_LIBS} oss)
+       ADD_DEFINITIONS(
+            -D__LINUX_OSS__
+       )
+    ENDIF(USE_AUDIO_OSS)
+ENDIF(UNIX AND NOT APPLE)
+
+IF (APPLE)
+ ADD_DEFINITIONS(
+   -D__MACOSX_CORE__
+ )    
+
+FIND_LIBRARY(COREAUDIO_LIBRARY CoreAudio)
+FIND_LIBRARY(COREFOUNDATION_LIBRARY CoreFoundation)
+SET (AUDIO_LIBS ${COREAUDIO_LIBRARY} ${COREFOUNDATION_LIBRARY} ${AUDIO_LIBS} )
+ENDIF (APPLE)
+
+IF (USE_HAMLIB)
+    SET (
+        HAMLIB_SOURCES 
+        RigThread.cpp
+        RigThread.h
+    )
+ENDIF()
+
+SOAPY_SDR_MODULE_UTIL(
+    TARGET audioSupport
+    SOURCES
+        SoapyAudio.hpp
+        Registation.cpp
+        Settings.cpp
+        Streaming.cpp
+        RtAudio/RtAudio.cpp
+        RtAudio/RtAudio.h        
+        ${HAMLIB_SOURCES}
+    LIBRARIES
+        ${AUDIO_LIBS}
+)
diff --git a/Findhamlib.cmake b/Findhamlib.cmake
new file mode 100644
index 0000000..abed74b
--- /dev/null
+++ b/Findhamlib.cmake
@@ -0,0 +1,59 @@
+# - Try to find hamlib
+# Once done, this will define:
+#
+#  hamlib_FOUND - system has Hamlib-2
+#  hamlib_INCLUDE_DIRS - the Hamlib-2 include directories
+#  hamlib_LIBRARIES - link these to use Hamlib-2
+#  hamlib_STATIC_FOUND - system has Hamlib-2 static archive
+#  hamlib_STATIC_LIBRARIES - link these to use Hamlib-2 static archive
+
+include (LibFindMacros)
+
+# pkg-config?
+find_path (__hamlib_pc_path NAMES hamlib.pc
+  PATH_SUFFIXES lib/pkgconfig
+)
+if (__hamlib_pc_path)
+  set (ENV{PKG_CONFIG_PATH} "${__hamlib_pc_path}" "$ENV{PKG_CONFIG_PATH}")
+  unset (__hamlib_pc_path CACHE)
+endif ()
+
+# Use pkg-config to get hints about paths, libs and, flags
+unset (__pkg_config_checked_hamlib CACHE)
+libfind_pkg_check_modules (PC_HAMLIB hamlib)
+
+if (NOT PC_HAMLIB_STATIC_LIBRARIES)
+  if (WIN32)
+    set (PC_HAMLIB_STATIC_LIBRARIES hamlib ws2_32)
+  else ()
+    set (PC_HAMLIB_STATIC_LIBRARIES hamlib m dl usb)
+  endif ()
+endif ()
+
+# The libraries
+libfind_library (hamlib hamlib)
+libfind_library (hamlib_STATIC libhamlib.a)
+
+find_path (hamlib_INCLUDE_DIR hamlib/rig.h)
+
+# Set the include dir variables and the libraries and let libfind_process do the rest
+set (hamlib_PROCESS_INCLUDES hamlib_INCLUDE_DIR)
+set (hamlib_PROCESS_LIBS hamlib_LIBRARY)
+libfind_process (hamlib)
+
+set (hamlib_STATIC_PROCESS_INCLUDES hamlib_STATIC_INCLUDE_DIR)
+set (hamlib_STATIC_PROCESS_LIBS hamlib_STATIC_LIBRARY PC_HAMLIB_STATIC_LIBRARIES)
+libfind_process (hamlib_STATIC)
+
+# make sure we return a full path for the library we return
+if (hamlib_FOUND)
+  list (REMOVE_ITEM hamlib_LIBRARIES hamlib)
+  if (hamlib_STATIC_LIBRARIES)
+    list (REMOVE_ITEM hamlib_STATIC_LIBRARIES hamlib)
+  endif ()
+endif ()
+
+# Handle the  QUIETLY and REQUIRED  arguments and set  HAMLIB_FOUND to
+# TRUE if all listed variables are TRUE
+include (FindPackageHandleStandardArgs)
+find_package_handle_standard_args (hamlib DEFAULT_MSG hamlib_INCLUDE_DIRS hamlib_LIBRARY hamlib_LIBRARIES)
diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..439cd08
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Charles J. Cliffe
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
\ No newline at end of file
diff --git a/LibFindMacros.cmake b/LibFindMacros.cmake
new file mode 100644
index 0000000..69975c5
--- /dev/null
+++ b/LibFindMacros.cmake
@@ -0,0 +1,99 @@
+# Works the same as find_package, but forwards the "REQUIRED" and "QUIET" arguments
+# used for the current package. For this to work, the first parameter must be the
+# prefix of the current package, then the prefix of the new package etc, which are
+# passed to find_package.
+macro (libfind_package PREFIX)
+  set (LIBFIND_PACKAGE_ARGS ${ARGN})
+  if (${PREFIX}_FIND_QUIETLY)
+    set (LIBFIND_PACKAGE_ARGS ${LIBFIND_PACKAGE_ARGS} QUIET)
+  endif (${PREFIX}_FIND_QUIETLY)
+  if (${PREFIX}_FIND_REQUIRED)
+    set (LIBFIND_PACKAGE_ARGS ${LIBFIND_PACKAGE_ARGS} REQUIRED)
+  endif (${PREFIX}_FIND_REQUIRED)
+  find_package(${LIBFIND_PACKAGE_ARGS})
+endmacro (libfind_package)
+
+# CMake developers made the UsePkgConfig system deprecated in the same release (2.6)
+# where they added pkg_check_modules. Consequently I need to support both in my scripts
+# to avoid those deprecated warnings. Here's a helper that does just that.
+# Works identically to pkg_check_modules, except that no checks are needed prior to use.
+macro (libfind_pkg_check_modules PREFIX PKGNAME)
+  if (${CMAKE_MAJOR_VERSION} EQUAL 2 AND ${CMAKE_MINOR_VERSION} EQUAL 4)
+    include(UsePkgConfig)
+    pkgconfig(${PKGNAME} ${PREFIX}_INCLUDE_DIRS ${PREFIX}_LIBRARY_DIRS ${PREFIX}_LDFLAGS ${PREFIX}_CFLAGS)
+  else (${CMAKE_MAJOR_VERSION} EQUAL 2 AND ${CMAKE_MINOR_VERSION} EQUAL 4)
+    find_package(PkgConfig)
+    if (PKG_CONFIG_FOUND)
+      pkg_check_modules(${PREFIX} ${PKGNAME})
+    endif (PKG_CONFIG_FOUND)
+  endif (${CMAKE_MAJOR_VERSION} EQUAL 2 AND ${CMAKE_MINOR_VERSION} EQUAL 4)
+endmacro (libfind_pkg_check_modules)
+
+# Do the final processing once the paths have been detected.
+# If include dirs are needed, ${PREFIX}_PROCESS_INCLUDES should be set to contain
+# all the variables, each of which contain one include directory.
+# Ditto for ${PREFIX}_PROCESS_LIBS and library files.
+# Will set ${PREFIX}_FOUND, ${PREFIX}_INCLUDE_DIRS and ${PREFIX}_LIBRARIES.
+# Also handles errors in case library detection was required, etc.
+macro (libfind_process PREFIX)
+  # Skip processing if already processed during this run
+  if (NOT ${PREFIX}_FOUND)
+    # Start with the assumption that the library was found
+    set (${PREFIX}_FOUND TRUE)
+
+    # Process all includes and set _FOUND to false if any are missing
+    foreach (i ${${PREFIX}_PROCESS_INCLUDES})
+      if (${i})
+        set (${PREFIX}_INCLUDE_DIRS ${${PREFIX}_INCLUDE_DIRS} ${${i}})
+        mark_as_advanced(${i})
+      else (${i})
+        set (${PREFIX}_FOUND FALSE)
+      endif (${i})
+    endforeach (i)
+
+    # Process all libraries and set _FOUND to false if any are missing
+    foreach (i ${${PREFIX}_PROCESS_LIBS})
+      if (${i})
+        set (${PREFIX}_LIBRARIES ${${PREFIX}_LIBRARIES} ${${i}})
+        mark_as_advanced(${i})
+      else (${i})
+        set (${PREFIX}_FOUND FALSE)
+      endif (${i})
+    endforeach (i)
+
+    # Print message and/or exit on fatal error
+    if (${PREFIX}_FOUND)
+      if (NOT ${PREFIX}_FIND_QUIETLY)
+        message (STATUS "Found ${PREFIX} ${${PREFIX}_VERSION}")
+      endif (NOT ${PREFIX}_FIND_QUIETLY)
+    else (${PREFIX}_FOUND)
+      if (${PREFIX}_FIND_REQUIRED)
+        foreach (i ${${PREFIX}_PROCESS_INCLUDES} ${${PREFIX}_PROCESS_LIBS})
+          message("${i}=${${i}}")
+        endforeach (i)
+        message (FATAL_ERROR "Required library ${PREFIX} NOT FOUND.\nInstall the library (dev version) and try again. If the library is already installed, use ccmake to set the missing variables manually.")
+      endif (${PREFIX}_FIND_REQUIRED)
+    endif (${PREFIX}_FOUND)
+  endif (NOT ${PREFIX}_FOUND)
+endmacro (libfind_process)
+
+macro(libfind_library PREFIX basename)
+  set(TMP "")
+  if(MSVC80)
+    set(TMP -vc80)
+  endif(MSVC80)
+  if(MSVC90)
+    set(TMP -vc90)
+  endif(MSVC90)
+  set(${PREFIX}_LIBNAMES ${basename}${TMP})
+  if(${ARGC} GREATER 2)
+    set(${PREFIX}_LIBNAMES ${basename}${TMP}-${ARGV2})
+    string(REGEX REPLACE "\\." "_" TMP ${${PREFIX}_LIBNAMES})
+    set(${PREFIX}_LIBNAMES ${${PREFIX}_LIBNAMES} ${TMP})
+  endif(${ARGC} GREATER 2)
+  find_library(${PREFIX}_LIBRARY
+    NAMES ${${PREFIX}_LIBNAMES}
+    PATHS ${${PREFIX}_PKGCONF_LIBRARY_DIRS}
+  )
+endmacro(libfind_library)
+
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..57e81b3
--- /dev/null
+++ b/README.md
@@ -0,0 +1,11 @@
+# Soapy SDR plugin for Audio devices
+
+##Dependencies
+
+* SoapySDR - https://github.com/pothosware/SoapySDR/wiki
+* rtaudio - https://www.music.mcgill.ca/~gary/rtaudio/
+* hamlib - http://sourceforge.net/projects/hamlib/
+
+##Documentation
+
+* https://github.com/pothosware/SoapyAudio/wiki
diff --git a/Registation.cpp b/Registation.cpp
new file mode 100644
index 0000000..82a3452
--- /dev/null
+++ b/Registation.cpp
@@ -0,0 +1,112 @@
+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2015 Charles J. Cliffe
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "SoapyAudio.hpp"
+#include <SoapySDR/Registry.hpp>
+#include <cstdlib> //malloc
+
+static std::vector<SoapySDR::Kwargs> findAudio(const SoapySDR::Kwargs &args)
+{
+    std::vector<SoapySDR::Kwargs> results;
+
+    RtAudio endac;
+
+    int numDevices = endac.getDeviceCount();
+
+    for (int i = 0; i < numDevices; i++) {
+        RtAudio::DeviceInfo info = endac.getDeviceInfo(i);
+        SoapySDR::Kwargs soapyInfo;
+
+        soapyInfo["device_id"] = std::to_string(i);
+        soapyInfo["label"] = info.name;
+        soapyInfo["default_output"] = info.isDefaultOutput ? "True" : "False";
+        soapyInfo["default_input"] = info.isDefaultInput ? "True" : "False";
+
+        // std::cout << "\tInput channels: " << info.inputChannels << std::endl;
+        // std::cout << "\tOutput channels: " << info.outputChannels << std::endl;
+        // std::cout << "\tDuplex channels: " << info.duplexChannels << std::endl;
+
+        // std::cout << "\t" << "Native formats:" << std::endl;
+        // RtAudioFormat nFormats = info.nativeFormats;
+        // if (nFormats & RTAUDIO_SINT8) {
+        //     std::cout << "\t\t8-bit signed integer." << std::endl;
+        // }
+        // if (nFormats & RTAUDIO_SINT16) {
+        //     std::cout << "\t\t16-bit signed integer." << std::endl;
+        // }
+        // if (nFormats & RTAUDIO_SINT24) {
+        //     std::cout << "\t\t24-bit signed integer." << std::endl;
+        // }
+        // if (nFormats & RTAUDIO_SINT32) {
+        //     std::cout << "\t\t32-bit signed integer." << std::endl;
+        // }
+        // if (nFormats & RTAUDIO_FLOAT32) {
+        //     std::cout << "\t\t32-bit float normalized between plus/minus 1.0." << std::endl;
+        // }
+        // if (nFormats & RTAUDIO_FLOAT64) {
+        //     std::cout << "\t\t32-bit float normalized between plus/minus 1.0." << std::endl;
+        // }
+
+        // filtering
+        if (info.inputChannels == 0) { // filter output devices for now
+            continue;
+        }
+        
+        if (args.count("device_id") != 0)
+        {
+            if (args.at("device_id") != soapyInfo.at("device_id"))
+            {
+                continue;
+            }
+            SoapySDR_logf(SOAPY_SDR_DEBUG, "Found device by device_id %s", soapyInfo.at("device_id").c_str());
+        }
+        
+        results.push_back(soapyInfo);
+    }
+    
+#ifdef USE_HAMLIB
+	rig_set_debug(RIG_DEBUG_ERR);
+	rig_load_all_backends();
+    SoapyAudio::rigCaps.clear();    
+	rig_list_foreach(SoapyAudio::add_hamlib_rig, 0);    
+    std::sort(SoapyAudio::rigCaps.begin(), SoapyAudio::rigCaps.end(), rigGreater());
+#endif
+
+    return results;
+}
+
+#ifdef USE_HAMLIB
+int SoapyAudio::add_hamlib_rig(const struct rig_caps *rc, void* f)
+{
+    rigCaps.push_back(rc);
+	return 1;
+}
+#endif
+
+static SoapySDR::Device *makeAudio(const SoapySDR::Kwargs &args)
+{
+    return new SoapyAudio(args);
+}
+
+static SoapySDR::Registry registerAudio("audio", &findAudio, &makeAudio, SOAPY_SDR_ABI_VERSION);
diff --git a/RigThread.cpp b/RigThread.cpp
new file mode 100644
index 0000000..ac96cc2
--- /dev/null
+++ b/RigThread.cpp
@@ -0,0 +1,101 @@
+#include "SoapyAudio.hpp"
+
+#ifdef USE_HAMLIB
+RigThread::RigThread() {
+    terminated.store(true);
+}
+
+RigThread::~RigThread() {
+
+}
+
+#ifdef __APPLE__
+void *RigThread::threadMain() {
+    terminated.store(false);
+    run();
+    return this;
+};
+
+void *RigThread::pthread_helper(void *context) {
+    return ((RigThread *) context)->threadMain();
+};
+#else
+void RigThread::threadMain() {
+    terminated.store(false);
+    run();
+};
+#endif
+
+void RigThread::setup(rig_model_t rig_model, std::string rig_file, int serial_rate) {
+    rigModel = rig_model;
+    rigFile = rig_file;
+    serialRate = serial_rate;
+};
+
+void RigThread::run() {
+    int retcode, status;
+
+    SoapySDR_log(SOAPY_SDR_DEBUG, "Rig thread starting.");    
+
+    rig = rig_init(rigModel);
+	strncpy(rig->state.rigport.pathname, rigFile.c_str(), FILPATHLEN - 1);
+	rig->state.rigport.parm.serial.rate = serialRate;
+	retcode = rig_open(rig);
+    
+    if (retcode != 0) {
+        SoapySDR_log(SOAPY_SDR_ERROR, "Rig failed to init.");
+        terminated.store(true);
+        return;
+    }
+    
+	char *info_buf = (char *)rig_get_info(rig);
+    
+    if (info_buf != nullptr) {
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "Rig Info: %s", info_buf);
+    }
+    
+    while (!terminated.load()) {
+        std::this_thread::sleep_for(std::chrono::milliseconds(150));
+        if (freqChanged.load()) {
+            status = rig_get_freq(rig, RIG_VFO_CURR, &freq);
+            if (freq != newFreq) {
+                freq = newFreq;
+                rig_set_freq(rig, RIG_VFO_CURR, freq);
+                SoapySDR_logf(SOAPY_SDR_DEBUG, "Set Rig Freq: %f", newFreq);
+            }
+            
+            freqChanged.store(false);
+        } else {
+            status = rig_get_freq(rig, RIG_VFO_CURR, &freq);
+        }
+        
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "Rig Freq: %f", freq);
+    }
+    
+    rig_close(rig);
+    rig_cleanup(rig);
+    
+    SoapySDR_log(SOAPY_SDR_DEBUG, "Rig thread exiting.");    
+};
+
+freq_t RigThread::getFrequency() {
+    if (freqChanged.load()) {
+        return newFreq;
+    } else {
+        return freq;
+    }
+}
+
+void RigThread::setFrequency(freq_t new_freq) {
+    newFreq = new_freq;
+    freqChanged.store(true);
+}
+
+void RigThread::terminate() {
+    terminated.store(true);
+};
+
+bool RigThread::isTerminated() {
+    return terminated.load();
+}
+#endif
\ No newline at end of file
diff --git a/RigThread.h b/RigThread.h
new file mode 100644
index 0000000..a0d39a4
--- /dev/null
+++ b/RigThread.h
@@ -0,0 +1,49 @@
+#pragma once
+
+#include <hamlib/rig.h>
+#include <hamlib/riglist.h>
+
+#ifdef USE_HAMLIB
+struct rigGreater
+{
+    bool operator()( const struct rig_caps *lx, const struct rig_caps *rx ) const {
+        std::string ln(std::string(std::string(lx->mfg_name) + " " + std::string(lx->model_name)));
+        std::string rn(std::string(std::string(rx->mfg_name) + " " + std::string(rx->model_name)));
+    	return ln.compare(rn)<0;
+    }
+};
+
+class RigThread {
+public:
+    RigThread();
+    ~RigThread();
+
+    void *pthread_helper(void *context);
+
+#ifdef __APPLE__
+    void *threadMain();
+#else
+    void threadMain();
+#endif
+
+    void setup(rig_model_t rig_model, std::string rig_file, int serial_rate);
+    void run();
+
+    void terminate();
+    bool isTerminated();
+
+    freq_t getFrequency();
+    void setFrequency(freq_t new_freq);
+    
+private:
+	RIG *rig;
+    rig_model_t rigModel;
+    std::string rigFile;
+    int serialRate;
+    
+    freq_t freq;
+    freq_t newFreq;
+    std::atomic_bool terminated, freqChanged;
+};
+
+#endif
\ No newline at end of file
diff --git a/RtAudio/FunctionDiscoveryKeys_devpkey.h b/RtAudio/FunctionDiscoveryKeys_devpkey.h
new file mode 100644
index 0000000..854244d
--- /dev/null
+++ b/RtAudio/FunctionDiscoveryKeys_devpkey.h
@@ -0,0 +1,212 @@
+#pragma once
+
+/*++
+
+Copyright (c) Microsoft Corporation.  All rights reserved.
+
+Module Name:
+
+    devpkey.h
+
+Abstract:
+
+    Defines property keys for the Plug and Play Device Property API.
+
+Author:
+
+    Jim Cavalaris (jamesca) 10-14-2003
+
+Environment:
+
+    User-mode only.
+
+Revision History:
+
+    14-October-2003     jamesca
+
+        Creation and initial implementation.
+
+    20-June-2006        dougb
+
+        Copied Jim's version replaced "DEFINE_DEVPROPKEY(DEVPKEY_" with "DEFINE_PROPERTYKEY(PKEY_"
+    
+--*/
+
+//#include <devpropdef.h>
+
+//
+// _NAME
+//
+
+DEFINE_PROPERTYKEY(PKEY_NAME,                          0xb725f130, 0x47ef, 0x101a, 0xa5, 0xf1, 0x02, 0x60, 0x8c, 0x9e, 0xeb, 0xac, 10);    // DEVPROP_TYPE_STRING
+
+//
+// Device properties
+// These PKEYs correspond to the old setupapi SPDRP_XXX properties
+//
+DEFINE_PROPERTYKEY(PKEY_Device_DeviceDesc,             0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 2);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_HardwareIds,            0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 3);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_CompatibleIds,          0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 4);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_Service,                0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 6);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_Class,                  0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 9);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_ClassGuid,              0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 10);    // DEVPROP_TYPE_GUID
+DEFINE_PROPERTYKEY(PKEY_Device_Driver,                 0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 11);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_ConfigFlags,            0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 12);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_Manufacturer,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 13);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_FriendlyName,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 14);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_LocationInfo,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 15);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_PDOName,                0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 16);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_Capabilities,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 17);    // DEVPROP_TYPE_UNINT32
+DEFINE_PROPERTYKEY(PKEY_Device_UINumber,               0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 18);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_UpperFilters,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 19);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_LowerFilters,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 20);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_BusTypeGuid,            0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 21);    // DEVPROP_TYPE_GUID
+DEFINE_PROPERTYKEY(PKEY_Device_LegacyBusType,          0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 22);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_BusNumber,              0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 23);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_EnumeratorName,         0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 24);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_Security,               0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 25);    // DEVPROP_TYPE_SECURITY_DESCRIPTOR
+DEFINE_PROPERTYKEY(PKEY_Device_SecuritySDS,            0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 26);    // DEVPROP_TYPE_SECURITY_DESCRIPTOR_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DevType,                0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 27);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_Exclusive,              0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 28);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_Characteristics,        0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 29);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_Address,                0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 30);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_UINumberDescFormat,     0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 31);    // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_PowerData,              0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 32);    // DEVPROP_TYPE_BINARY
+DEFINE_PROPERTYKEY(PKEY_Device_RemovalPolicy,          0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 33);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_RemovalPolicyDefault,   0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 34);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_RemovalPolicyOverride,  0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 35);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_InstallState,           0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 36);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_LocationPaths,          0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 37);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_BaseContainerId,        0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67, 0xd1, 0x46, 0xa8, 0x50, 0xe0, 38);    // DEVPROP_TYPE_GUID
+
+//
+// Device properties
+// These PKEYs correspond to a device's status and problem code
+//
+DEFINE_PROPERTYKEY(PKEY_Device_DevNodeStatus,          0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 2);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_ProblemCode,            0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 3);     // DEVPROP_TYPE_UINT32
+
+//
+// Device properties
+// These PKEYs correspond to device relations
+//
+DEFINE_PROPERTYKEY(PKEY_Device_EjectionRelations,      0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 4);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_RemovalRelations,       0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 5);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_PowerRelations,         0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 6);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_BusRelations,           0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 7);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_Parent,                 0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 8);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_Children,               0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 9);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_Siblings,               0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 10);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_TransportRelations,     0x4340a6c5, 0x93fa, 0x4706, 0x97, 0x2c, 0x7b, 0x64, 0x80, 0x08, 0xa5, 0xa7, 11);    // DEVPROP_TYPE_STRING_LIST
+
+//
+// Other Device properties
+//
+DEFINE_PROPERTYKEY(PKEY_Device_Reported,               0x80497100, 0x8c73, 0x48b9, 0xaa, 0xd9, 0xce, 0x38, 0x7e, 0x19, 0xc5, 0x6e, 2);     // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_Device_Legacy,                 0x80497100, 0x8c73, 0x48b9, 0xaa, 0xd9, 0xce, 0x38, 0x7e, 0x19, 0xc5, 0x6e, 3);     // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_Device_InstanceId,             0x78c34fc8, 0x104a, 0x4aca, 0x9e, 0xa4, 0x52, 0x4d, 0x52, 0x99, 0x6e, 0x57, 256);   // DEVPROP_TYPE_STRING
+
+DEFINE_PROPERTYKEY(PKEY_Device_ContainerId,            0x8c7ed206, 0x3f8a, 0x4827, 0xb3, 0xab, 0xae, 0x9e, 0x1f, 0xae, 0xfc, 0x6c, 2);     // DEVPROP_TYPE_GUID
+
+DEFINE_PROPERTYKEY(PKEY_Device_ModelId,                0x80d81ea6, 0x7473, 0x4b0c, 0x82, 0x16, 0xef, 0xc1, 0x1a, 0x2c, 0x4c, 0x8b, 2);     // DEVPROP_TYPE_GUID
+
+DEFINE_PROPERTYKEY(PKEY_Device_FriendlyNameAttributes, 0x80d81ea6, 0x7473, 0x4b0c, 0x82, 0x16, 0xef, 0xc1, 0x1a, 0x2c, 0x4c, 0x8b, 3);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_ManufacturerAttributes, 0x80d81ea6, 0x7473, 0x4b0c, 0x82, 0x16, 0xef, 0xc1, 0x1a, 0x2c, 0x4c, 0x8b, 4);     // DEVPROP_TYPE_UINT32
+
+DEFINE_PROPERTYKEY(PKEY_Device_PresenceNotForDevice,   0x80d81ea6, 0x7473, 0x4b0c, 0x82, 0x16, 0xef, 0xc1, 0x1a, 0x2c, 0x4c, 0x8b, 5);     // DEVPROP_TYPE_BOOLEAN
+
+
+DEFINE_PROPERTYKEY(PKEY_Numa_Proximity_Domain,         0x540b947e, 0x8b40, 0x45bc, 0xa8, 0xa2, 0x6a, 0x0b, 0x89, 0x4c, 0xbd, 0xa2, 1);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_DHP_Rebalance_Policy,   0x540b947e, 0x8b40, 0x45bc, 0xa8, 0xa2, 0x6a, 0x0b, 0x89, 0x4c, 0xbd, 0xa2, 2);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_Numa_Node,              0x540b947e, 0x8b40, 0x45bc, 0xa8, 0xa2, 0x6a, 0x0b, 0x89, 0x4c, 0xbd, 0xa2, 3);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_BusReportedDeviceDesc,  0x540b947e, 0x8b40, 0x45bc, 0xa8, 0xa2, 0x6a, 0x0b, 0x89, 0x4c, 0xbd, 0xa2, 4);     // DEVPROP_TYPE_STRING
+
+DEFINE_PROPERTYKEY(PKEY_Device_InstallInProgress,      0x83da6326, 0x97a6, 0x4088, 0x94, 0x53, 0xa1, 0x92, 0x3f, 0x57, 0x3b, 0x29, 9);     // DEVPROP_TYPE_BOOLEAN
+
+//
+// Device driver properties
+//
+DEFINE_PROPERTYKEY(PKEY_Device_DriverDate,             0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 2);      // DEVPROP_TYPE_FILETIME
+DEFINE_PROPERTYKEY(PKEY_Device_DriverVersion,          0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 3);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverDesc,             0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 4);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverInfPath,          0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 5);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverInfSection,       0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 6);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverInfSectionExt,    0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 7);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_MatchingDeviceId,       0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 8);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverProvider,         0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 9);      // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverPropPageProvider, 0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 10);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverCoInstallers,     0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 11);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_Device_ResourcePickerTags,     0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 12);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_ResourcePickerExceptions, 0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 13); // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_Device_DriverRank,             0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 14);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_DriverLogoLevel,        0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 15);     // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_Device_NoConnectSound,         0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 17);     // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_Device_GenericDriverInstalled, 0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 18);     // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_Device_AdditionalSoftwareRequested, 0xa8b865dd, 0x2e3d, 0x4094, 0xad, 0x97, 0xe5, 0x93, 0xa7, 0xc, 0x75, 0xd6, 19);// DEVPROP_TYPE_BOOLEAN
+
+//
+// Device safe-removal properties
+//
+DEFINE_PROPERTYKEY(PKEY_Device_SafeRemovalRequired,    0xafd97640,  0x86a3, 0x4210, 0xb6, 0x7c, 0x28, 0x9c, 0x41, 0xaa, 0xbe, 0x55, 2);    // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_Device_SafeRemovalRequiredOverride, 0xafd97640,  0x86a3, 0x4210, 0xb6, 0x7c, 0x28, 0x9c, 0x41, 0xaa, 0xbe, 0x55, 3);// DEVPROP_TYPE_BOOLEAN
+
+
+//
+// Device properties that were set by the driver package that was installed
+// on the device.
+//
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_Model,                  0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 2);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_VendorWebSite,          0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 3);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_DetailedDescription,    0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 4);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_DocumentationLink,      0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 5);     // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_Icon,                   0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 6);     // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_DrvPkg_BrandingIcon,           0xcf73bb51, 0x3abf, 0x44a2, 0x85, 0xe0, 0x9a, 0x3d, 0xc7, 0xa1, 0x21, 0x32, 7);     // DEVPROP_TYPE_STRING_LIST
+
+//
+// Device setup class properties
+// These PKEYs correspond to the old setupapi SPCRP_XXX properties
+//
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_UpperFilters,      0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 19);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_LowerFilters,      0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 20);    // DEVPROP_TYPE_STRING_LIST
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_Security,          0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 25);    // DEVPROP_TYPE_SECURITY_DESCRIPTOR
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_SecuritySDS,       0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 26);    // DEVPROP_TYPE_SECURITY_DESCRIPTOR_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_DevType,           0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 27);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_Exclusive,         0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 28);    // DEVPROP_TYPE_UINT32
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_Characteristics,   0x4321918b, 0xf69e, 0x470d, 0xa5, 0xde, 0x4d, 0x88, 0xc7, 0x5a, 0xd2, 0x4b, 29);    // DEVPROP_TYPE_UINT32
+
+//
+// Device setup class properties
+// These PKEYs correspond to registry values under the device class GUID key
+//
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_Name,              0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 2);  // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_ClassName,         0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 3);  // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_Icon,              0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 4);  // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_ClassInstaller,    0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 5);  // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_PropPageProvider,  0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 6);  // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_NoInstallClass,    0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 7);  // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_NoDisplayClass,    0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 8);  // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_SilentInstall,     0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 9);  // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_NoUseClass,        0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 10); // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_DefaultService,    0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 11); // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_IconPath,          0x259abffc, 0x50a7, 0x47ce, 0xaf, 0x8, 0x68, 0xc9, 0xa7, 0xd7, 0x33, 0x66, 12); // DEVPROP_TYPE_STRING_LIST
+
+//
+// Other Device setup class properties
+//
+DEFINE_PROPERTYKEY(PKEY_DeviceClass_ClassCoInstallers, 0x713d1703, 0xa2e2, 0x49f5, 0x92, 0x14, 0x56, 0x47, 0x2e, 0xf3, 0xda, 0x5c, 2); // DEVPROP_TYPE_STRING_LIST
+
+//
+// Device interface properties
+//
+DEFINE_PROPERTYKEY(PKEY_DeviceInterface_FriendlyName,  0x026e516e, 0xb814, 0x414b, 0x83, 0xcd, 0x85, 0x6d, 0x6f, 0xef, 0x48, 0x22, 2); // DEVPROP_TYPE_STRING
+DEFINE_PROPERTYKEY(PKEY_DeviceInterface_Enabled,       0x026e516e, 0xb814, 0x414b, 0x83, 0xcd, 0x85, 0x6d, 0x6f, 0xef, 0x48, 0x22, 3); // DEVPROP_TYPE_BOOLEAN
+DEFINE_PROPERTYKEY(PKEY_DeviceInterface_ClassGuid,     0x026e516e, 0xb814, 0x414b, 0x83, 0xcd, 0x85, 0x6d, 0x6f, 0xef, 0x48, 0x22, 4); // DEVPROP_TYPE_GUID
+
+//
+// Device interface class properties
+//
+DEFINE_PROPERTYKEY(PKEY_DeviceInterfaceClass_DefaultInterface,  0x14c83a99, 0x0b3f, 0x44b7, 0xbe, 0x4c, 0xa1, 0x78, 0xd3, 0x99, 0x05, 0x64, 2); // DEVPROP_TYPE_STRING
+
+
+
+
diff --git a/RtAudio/RtAudio.cpp b/RtAudio/RtAudio.cpp
new file mode 100644
index 0000000..af61bc7
--- /dev/null
+++ b/RtAudio/RtAudio.cpp
@@ -0,0 +1,10229 @@
+/************************************************************************/
+/*! \class RtAudio
+    \brief Realtime audio i/o C++ classes.
+
+    RtAudio provides a common API (Application Programming Interface)
+    for realtime audio input/output across Linux (native ALSA, Jack,
+    and OSS), Macintosh OS X (CoreAudio and Jack), and Windows
+    (DirectSound, ASIO and WASAPI) operating systems.
+
+    RtAudio WWW site: http://www.music.mcgill.ca/~gary/rtaudio/
+
+    RtAudio: realtime audio i/o C++ classes
+    Copyright (c) 2001-2016 Gary P. Scavone
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation files
+    (the "Software"), to deal in the Software without restriction,
+    including without limitation the rights to use, copy, modify, merge,
+    publish, distribute, sublicense, and/or sell copies of the Software,
+    and to permit persons to whom the Software is furnished to do so,
+    subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    Any person wishing to distribute modifications to the Software is
+    asked to send the modifications to the original developer so that
+    they can be incorporated into the canonical version.  This is,
+    however, not a binding provision of this license.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+    ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+    CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+/************************************************************************/
+
+// RtAudio: Version 4.1.2
+
+#include "RtAudio.h"
+#include <iostream>
+#include <cstdlib>
+#include <cstring>
+#include <climits>
+#include <algorithm>
+
+// Static variable definitions.
+const unsigned int RtApi::MAX_SAMPLE_RATES = 14;
+const unsigned int RtApi::SAMPLE_RATES[] = {
+  4000, 5512, 8000, 9600, 11025, 16000, 22050,
+  32000, 44100, 48000, 88200, 96000, 176400, 192000
+};
+
+#if defined(__WINDOWS_DS__) || defined(__WINDOWS_ASIO__) || defined(__WINDOWS_WASAPI__)
+  #define MUTEX_INITIALIZE(A) InitializeCriticalSection(A)
+  #define MUTEX_DESTROY(A)    DeleteCriticalSection(A)
+  #define MUTEX_LOCK(A)       EnterCriticalSection(A)
+  #define MUTEX_UNLOCK(A)     LeaveCriticalSection(A)
+
+  #include "tchar.h"
+
+  static std::string convertCharPointerToStdString(const char *text)
+  {
+    return std::string(text);
+  }
+
+  static std::string convertCharPointerToStdString(const wchar_t *text)
+  {
+    int length = WideCharToMultiByte(CP_UTF8, 0, text, -1, NULL, 0, NULL, NULL);
+    std::string s( length-1, '\0' );
+    WideCharToMultiByte(CP_UTF8, 0, text, -1, &s[0], length, NULL, NULL);
+    return s;
+  }
+
+#elif defined(__LINUX_ALSA__) || defined(__LINUX_PULSE__) || defined(__UNIX_JACK__) || defined(__LINUX_OSS__) || defined(__MACOSX_CORE__)
+  // pthread API
+  #define MUTEX_INITIALIZE(A) pthread_mutex_init(A, NULL)
+  #define MUTEX_DESTROY(A)    pthread_mutex_destroy(A)
+  #define MUTEX_LOCK(A)       pthread_mutex_lock(A)
+  #define MUTEX_UNLOCK(A)     pthread_mutex_unlock(A)
+#else
+  #define MUTEX_INITIALIZE(A) abs(*A) // dummy definitions
+  #define MUTEX_DESTROY(A)    abs(*A) // dummy definitions
+#endif
+
+// *************************************************** //
+//
+// RtAudio definitions.
+//
+// *************************************************** //
+
+std::string RtAudio :: getVersion( void ) throw()
+{
+  return RTAUDIO_VERSION;
+}
+
+void RtAudio :: getCompiledApi( std::vector<RtAudio::Api> &apis ) throw()
+{
+  apis.clear();
+
+  // The order here will control the order of RtAudio's API search in
+  // the constructor.
+#if defined(__UNIX_JACK__)
+  apis.push_back( UNIX_JACK );
+#endif
+#if defined(__LINUX_ALSA__)
+  apis.push_back( LINUX_ALSA );
+#endif
+#if defined(__LINUX_PULSE__)
+  apis.push_back( LINUX_PULSE );
+#endif
+#if defined(__LINUX_OSS__)
+  apis.push_back( LINUX_OSS );
+#endif
+#if defined(__WINDOWS_ASIO__)
+  apis.push_back( WINDOWS_ASIO );
+#endif
+#if defined(__WINDOWS_WASAPI__)
+  apis.push_back( WINDOWS_WASAPI );
+#endif
+#if defined(__WINDOWS_DS__)
+  apis.push_back( WINDOWS_DS );
+#endif
+#if defined(__MACOSX_CORE__)
+  apis.push_back( MACOSX_CORE );
+#endif
+#if defined(__RTAUDIO_DUMMY__)
+  apis.push_back( RTAUDIO_DUMMY );
+#endif
+}
+
+void RtAudio :: openRtApi( RtAudio::Api api )
+{
+  if ( rtapi_ )
+    delete rtapi_;
+  rtapi_ = 0;
+
+#if defined(__UNIX_JACK__)
+  if ( api == UNIX_JACK )
+    rtapi_ = new RtApiJack();
+#endif
+#if defined(__LINUX_ALSA__)
+  if ( api == LINUX_ALSA )
+    rtapi_ = new RtApiAlsa();
+#endif
+#if defined(__LINUX_PULSE__)
+  if ( api == LINUX_PULSE )
+    rtapi_ = new RtApiPulse();
+#endif
+#if defined(__LINUX_OSS__)
+  if ( api == LINUX_OSS )
+    rtapi_ = new RtApiOss();
+#endif
+#if defined(__WINDOWS_ASIO__)
+  if ( api == WINDOWS_ASIO )
+    rtapi_ = new RtApiAsio();
+#endif
+#if defined(__WINDOWS_WASAPI__)
+  if ( api == WINDOWS_WASAPI )
+    rtapi_ = new RtApiWasapi();
+#endif
+#if defined(__WINDOWS_DS__)
+  if ( api == WINDOWS_DS )
+    rtapi_ = new RtApiDs();
+#endif
+#if defined(__MACOSX_CORE__)
+  if ( api == MACOSX_CORE )
+    rtapi_ = new RtApiCore();
+#endif
+#if defined(__RTAUDIO_DUMMY__)
+  if ( api == RTAUDIO_DUMMY )
+    rtapi_ = new RtApiDummy();
+#endif
+}
+
+RtAudio :: RtAudio( RtAudio::Api api )
+{
+  rtapi_ = 0;
+
+  if ( api != UNSPECIFIED ) {
+    // Attempt to open the specified API.
+    openRtApi( api );
+    if ( rtapi_ ) return;
+
+    // No compiled support for specified API value.  Issue a debug
+    // warning and continue as if no API was specified.
+    std::cerr << "\nRtAudio: no compiled support for specified API argument!\n" << std::endl;
+  }
+
+  // Iterate through the compiled APIs and return as soon as we find
+  // one with at least one device or we reach the end of the list.
+  std::vector< RtAudio::Api > apis;
+  getCompiledApi( apis );
+  for ( unsigned int i=0; i<apis.size(); i++ ) {
+    openRtApi( apis[i] );
+    if ( rtapi_ && rtapi_->getDeviceCount() ) break;
+  }
+
+  if ( rtapi_ ) return;
+
+  // It should not be possible to get here because the preprocessor
+  // definition __RTAUDIO_DUMMY__ is automatically defined if no
+  // API-specific definitions are passed to the compiler. But just in
+  // case something weird happens, we'll thow an error.
+  std::string errorText = "\nRtAudio: no compiled API support found ... critical error!!\n\n";
+  throw( RtAudioError( errorText, RtAudioError::UNSPECIFIED ) );
+}
+
+RtAudio :: ~RtAudio() throw()
+{
+  if ( rtapi_ )
+    delete rtapi_;
+}
+
+void RtAudio :: openStream( RtAudio::StreamParameters *outputParameters,
+                            RtAudio::StreamParameters *inputParameters,
+                            RtAudioFormat format, unsigned int sampleRate,
+                            unsigned int *bufferFrames,
+                            RtAudioCallback callback, void *userData,
+                            RtAudio::StreamOptions *options,
+                            RtAudioErrorCallback errorCallback )
+{
+  return rtapi_->openStream( outputParameters, inputParameters, format,
+                             sampleRate, bufferFrames, callback,
+                             userData, options, errorCallback );
+}
+
+// *************************************************** //
+//
+// Public RtApi definitions (see end of file for
+// private or protected utility functions).
+//
+// *************************************************** //
+
+RtApi :: RtApi()
+{
+  stream_.state = STREAM_CLOSED;
+  stream_.mode = UNINITIALIZED;
+  stream_.apiHandle = 0;
+  stream_.userBuffer[0] = 0;
+  stream_.userBuffer[1] = 0;
+  MUTEX_INITIALIZE( &stream_.mutex );
+  showWarnings_ = true;
+  firstErrorOccurred_ = false;
+}
+
+RtApi :: ~RtApi()
+{
+  MUTEX_DESTROY( &stream_.mutex );
+}
+
+void RtApi :: openStream( RtAudio::StreamParameters *oParams,
+                          RtAudio::StreamParameters *iParams,
+                          RtAudioFormat format, unsigned int sampleRate,
+                          unsigned int *bufferFrames,
+                          RtAudioCallback callback, void *userData,
+                          RtAudio::StreamOptions *options,
+                          RtAudioErrorCallback errorCallback )
+{
+  if ( stream_.state != STREAM_CLOSED ) {
+    errorText_ = "RtApi::openStream: a stream is already open!";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+
+  // Clear stream information potentially left from a previously open stream.
+  clearStreamInfo();
+
+  if ( oParams && oParams->nChannels < 1 ) {
+    errorText_ = "RtApi::openStream: a non-NULL output StreamParameters structure cannot have an nChannels value less than one.";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+
+  if ( iParams && iParams->nChannels < 1 ) {
+    errorText_ = "RtApi::openStream: a non-NULL input StreamParameters structure cannot have an nChannels value less than one.";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+
+  if ( oParams == NULL && iParams == NULL ) {
+    errorText_ = "RtApi::openStream: input and output StreamParameters structures are both NULL!";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+
+  if ( formatBytes(format) == 0 ) {
+    errorText_ = "RtApi::openStream: 'format' parameter value is undefined.";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+
+  unsigned int nDevices = getDeviceCount();
+  unsigned int oChannels = 0;
+  if ( oParams ) {
+    oChannels = oParams->nChannels;
+    if ( oParams->deviceId >= nDevices ) {
+      errorText_ = "RtApi::openStream: output device parameter value is invalid.";
+      error( RtAudioError::INVALID_USE );
+      return;
+    }
+  }
+
+  unsigned int iChannels = 0;
+  if ( iParams ) {
+    iChannels = iParams->nChannels;
+    if ( iParams->deviceId >= nDevices ) {
+      errorText_ = "RtApi::openStream: input device parameter value is invalid.";
+      error( RtAudioError::INVALID_USE );
+      return;
+    }
+  }
+
+  bool result;
+
+  if ( oChannels > 0 ) {
+
+    result = probeDeviceOpen( oParams->deviceId, OUTPUT, oChannels, oParams->firstChannel,
+                              sampleRate, format, bufferFrames, options );
+    if ( result == false ) {
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+  }
+
+  if ( iChannels > 0 ) {
+
+    result = probeDeviceOpen( iParams->deviceId, INPUT, iChannels, iParams->firstChannel,
+                              sampleRate, format, bufferFrames, options );
+    if ( result == false ) {
+      if ( oChannels > 0 ) closeStream();
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+  }
+
+  stream_.callbackInfo.callback = (void *) callback;
+  stream_.callbackInfo.userData = userData;
+  stream_.callbackInfo.errorCallback = (void *) errorCallback;
+
+  if ( options ) options->numberOfBuffers = stream_.nBuffers;
+  stream_.state = STREAM_STOPPED;
+}
+
+unsigned int RtApi :: getDefaultInputDevice( void )
+{
+  // Should be implemented in subclasses if possible.
+  return 0;
+}
+
+unsigned int RtApi :: getDefaultOutputDevice( void )
+{
+  // Should be implemented in subclasses if possible.
+  return 0;
+}
+
+void RtApi :: closeStream( void )
+{
+  // MUST be implemented in subclasses!
+  return;
+}
+
+bool RtApi :: probeDeviceOpen( unsigned int /*device*/, StreamMode /*mode*/, unsigned int /*channels*/,
+                               unsigned int /*firstChannel*/, unsigned int /*sampleRate*/,
+                               RtAudioFormat /*format*/, unsigned int * /*bufferSize*/,
+                               RtAudio::StreamOptions * /*options*/ )
+{
+  // MUST be implemented in subclasses!
+  return FAILURE;
+}
+
+void RtApi :: tickStreamTime( void )
+{
+  // Subclasses that do not provide their own implementation of
+  // getStreamTime should call this function once per buffer I/O to
+  // provide basic stream time support.
+
+  stream_.streamTime += ( stream_.bufferSize * 1.0 / stream_.sampleRate );
+
+#if defined( HAVE_GETTIMEOFDAY )
+  gettimeofday( &stream_.lastTickTimestamp, NULL );
+#endif
+}
+
+long RtApi :: getStreamLatency( void )
+{
+  verifyStream();
+
+  long totalLatency = 0;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX )
+    totalLatency = stream_.latency[0];
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX )
+    totalLatency += stream_.latency[1];
+
+  return totalLatency;
+}
+
+double RtApi :: getStreamTime( void )
+{
+  verifyStream();
+
+#if defined( HAVE_GETTIMEOFDAY )
+  // Return a very accurate estimate of the stream time by
+  // adding in the elapsed time since the last tick.
+  struct timeval then;
+  struct timeval now;
+
+  if ( stream_.state != STREAM_RUNNING || stream_.streamTime == 0.0 )
+    return stream_.streamTime;
+
+  gettimeofday( &now, NULL );
+  then = stream_.lastTickTimestamp;
+  return stream_.streamTime +
+    ((now.tv_sec + 0.000001 * now.tv_usec) -
+     (then.tv_sec + 0.000001 * then.tv_usec));     
+#else
+  return stream_.streamTime;
+#endif
+}
+
+void RtApi :: setStreamTime( double time )
+{
+  verifyStream();
+
+  if ( time >= 0.0 )
+    stream_.streamTime = time;
+}
+
+unsigned int RtApi :: getStreamSampleRate( void )
+{
+ verifyStream();
+
+ return stream_.sampleRate;
+}
+
+
+// *************************************************** //
+//
+// OS/API-specific methods.
+//
+// *************************************************** //
+
+#if defined(__MACOSX_CORE__)
+
+// The OS X CoreAudio API is designed to use a separate callback
+// procedure for each of its audio devices.  A single RtAudio duplex
+// stream using two different devices is supported here, though it
+// cannot be guaranteed to always behave correctly because we cannot
+// synchronize these two callbacks.
+//
+// A property listener is installed for over/underrun information.
+// However, no functionality is currently provided to allow property
+// listeners to trigger user handlers because it is unclear what could
+// be done if a critical stream parameter (buffer size, sample rate,
+// device disconnect) notification arrived.  The listeners entail
+// quite a bit of extra code and most likely, a user program wouldn't
+// be prepared for the result anyway.  However, we do provide a flag
+// to the client callback function to inform of an over/underrun.
+
+// A structure to hold various information related to the CoreAudio API
+// implementation.
+struct CoreHandle {
+  AudioDeviceID id[2];    // device ids
+#if defined( MAC_OS_X_VERSION_10_5 ) && ( MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_5 )
+  AudioDeviceIOProcID procId[2];
+#endif
+  UInt32 iStream[2];      // device stream index (or first if using multiple)
+  UInt32 nStreams[2];     // number of streams to use
+  bool xrun[2];
+  char *deviceBuffer;
+  pthread_cond_t condition;
+  int drainCounter;       // Tracks callback counts when draining
+  bool internalDrain;     // Indicates if stop is initiated from callback or not.
+
+  CoreHandle()
+    :deviceBuffer(0), drainCounter(0), internalDrain(false) { nStreams[0] = 1; nStreams[1] = 1; id[0] = 0; id[1] = 0; xrun[0] = false; xrun[1] = false; }
+};
+
+RtApiCore:: RtApiCore()
+{
+#if defined( AVAILABLE_MAC_OS_X_VERSION_10_6_AND_LATER )
+  // This is a largely undocumented but absolutely necessary
+  // requirement starting with OS-X 10.6.  If not called, queries and
+  // updates to various audio device properties are not handled
+  // correctly.
+  CFRunLoopRef theRunLoop = NULL;
+  AudioObjectPropertyAddress property = { kAudioHardwarePropertyRunLoop,
+                                          kAudioObjectPropertyScopeGlobal,
+                                          kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectSetPropertyData( kAudioObjectSystemObject, &property, 0, NULL, sizeof(CFRunLoopRef), &theRunLoop);
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::RtApiCore: error setting run loop property!";
+    error( RtAudioError::WARNING );
+  }
+#endif
+}
+
+RtApiCore :: ~RtApiCore()
+{
+  // The subclass destructor gets called before the base class
+  // destructor, so close an existing stream before deallocating
+  // apiDeviceId memory.
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+}
+
+unsigned int RtApiCore :: getDeviceCount( void )
+{
+  // Find out how many audio devices there are, if any.
+  UInt32 dataSize;
+  AudioObjectPropertyAddress propertyAddress = { kAudioHardwarePropertyDevices, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectGetPropertyDataSize( kAudioObjectSystemObject, &propertyAddress, 0, NULL, &dataSize );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDeviceCount: OS-X error getting device info!";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  return dataSize / sizeof( AudioDeviceID );
+}
+
+unsigned int RtApiCore :: getDefaultInputDevice( void )
+{
+  unsigned int nDevices = getDeviceCount();
+  if ( nDevices <= 1 ) return 0;
+
+  AudioDeviceID id;
+  UInt32 dataSize = sizeof( AudioDeviceID );
+  AudioObjectPropertyAddress property = { kAudioHardwarePropertyDefaultInputDevice, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property, 0, NULL, &dataSize, &id );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDefaultInputDevice: OS-X system error getting device.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  dataSize *= nDevices;
+  AudioDeviceID deviceList[ nDevices ];
+  property.mSelector = kAudioHardwarePropertyDevices;
+  result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property, 0, NULL, &dataSize, (void *) &deviceList );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDefaultInputDevice: OS-X system error getting device IDs.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  for ( unsigned int i=0; i<nDevices; i++ )
+    if ( id == deviceList[i] ) return i;
+
+  errorText_ = "RtApiCore::getDefaultInputDevice: No default device found!";
+  error( RtAudioError::WARNING );
+  return 0;
+}
+
+unsigned int RtApiCore :: getDefaultOutputDevice( void )
+{
+  unsigned int nDevices = getDeviceCount();
+  if ( nDevices <= 1 ) return 0;
+
+  AudioDeviceID id;
+  UInt32 dataSize = sizeof( AudioDeviceID );
+  AudioObjectPropertyAddress property = { kAudioHardwarePropertyDefaultOutputDevice, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property, 0, NULL, &dataSize, &id );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDefaultOutputDevice: OS-X system error getting device.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  dataSize = sizeof( AudioDeviceID ) * nDevices;
+  AudioDeviceID deviceList[ nDevices ];
+  property.mSelector = kAudioHardwarePropertyDevices;
+  result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property, 0, NULL, &dataSize, (void *) &deviceList );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDefaultOutputDevice: OS-X system error getting device IDs.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  for ( unsigned int i=0; i<nDevices; i++ )
+    if ( id == deviceList[i] ) return i;
+
+  errorText_ = "RtApiCore::getDefaultOutputDevice: No default device found!";
+  error( RtAudioError::WARNING );
+  return 0;
+}
+
+RtAudio::DeviceInfo RtApiCore :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  // Get device ID
+  unsigned int nDevices = getDeviceCount();
+  if ( nDevices == 0 ) {
+    errorText_ = "RtApiCore::getDeviceInfo: no devices found!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  if ( device >= nDevices ) {
+    errorText_ = "RtApiCore::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  AudioDeviceID deviceList[ nDevices ];
+  UInt32 dataSize = sizeof( AudioDeviceID ) * nDevices;
+  AudioObjectPropertyAddress property = { kAudioHardwarePropertyDevices,
+                                          kAudioObjectPropertyScopeGlobal,
+                                          kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property,
+                                                0, NULL, &dataSize, (void *) &deviceList );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::getDeviceInfo: OS-X system error getting device IDs.";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  AudioDeviceID id = deviceList[ device ];
+
+  // Get the device name.
+  info.name.erase();
+  CFStringRef cfname;
+  dataSize = sizeof( CFStringRef );
+  property.mSelector = kAudioObjectPropertyManufacturer;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &cfname );
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceInfo: system error (" << getErrorCode( result ) << ") getting device manufacturer.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  //const char *mname = CFStringGetCStringPtr( cfname, CFStringGetSystemEncoding() );
+  int length = CFStringGetLength(cfname);
+  char *mname = (char *)malloc(length * 3 + 1);
+#if defined( UNICODE ) || defined( _UNICODE )
+  CFStringGetCString(cfname, mname, length * 3 + 1, kCFStringEncodingUTF8);
+#else
+  CFStringGetCString(cfname, mname, length * 3 + 1, CFStringGetSystemEncoding());
+#endif
+  info.name.append( (const char *)mname, strlen(mname) );
+  info.name.append( ": " );
+  CFRelease( cfname );
+  free(mname);
+
+  property.mSelector = kAudioObjectPropertyName;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &cfname );
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceInfo: system error (" << getErrorCode( result ) << ") getting device name.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  //const char *name = CFStringGetCStringPtr( cfname, CFStringGetSystemEncoding() );
+  length = CFStringGetLength(cfname);
+  char *name = (char *)malloc(length * 3 + 1);
+#if defined( UNICODE ) || defined( _UNICODE )
+  CFStringGetCString(cfname, name, length * 3 + 1, kCFStringEncodingUTF8);
+#else
+  CFStringGetCString(cfname, name, length * 3 + 1, CFStringGetSystemEncoding());
+#endif
+  info.name.append( (const char *)name, strlen(name) );
+  CFRelease( cfname );
+  free(name);
+
+  // Get the output stream "configuration".
+  AudioBufferList	*bufferList = nil;
+  property.mSelector = kAudioDevicePropertyStreamConfiguration;
+  property.mScope = kAudioDevicePropertyScopeOutput;
+  //  property.mElement = kAudioObjectPropertyElementWildcard;
+  dataSize = 0;
+  result = AudioObjectGetPropertyDataSize( id, &property, 0, NULL, &dataSize );
+  if ( result != noErr || dataSize == 0 ) {
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting output stream configuration info for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Allocate the AudioBufferList.
+  bufferList = (AudioBufferList *) malloc( dataSize );
+  if ( bufferList == NULL ) {
+    errorText_ = "RtApiCore::getDeviceInfo: memory error allocating output AudioBufferList.";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, bufferList );
+  if ( result != noErr || dataSize == 0 ) {
+    free( bufferList );
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting output stream configuration for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Get output channel information.
+  unsigned int i, nStreams = bufferList->mNumberBuffers;
+  for ( i=0; i<nStreams; i++ )
+    info.outputChannels += bufferList->mBuffers[i].mNumberChannels;
+  free( bufferList );
+
+  // Get the input stream "configuration".
+  property.mScope = kAudioDevicePropertyScopeInput;
+  result = AudioObjectGetPropertyDataSize( id, &property, 0, NULL, &dataSize );
+  if ( result != noErr || dataSize == 0 ) {
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting input stream configuration info for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Allocate the AudioBufferList.
+  bufferList = (AudioBufferList *) malloc( dataSize );
+  if ( bufferList == NULL ) {
+    errorText_ = "RtApiCore::getDeviceInfo: memory error allocating input AudioBufferList.";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, bufferList );
+  if (result != noErr || dataSize == 0) {
+    free( bufferList );
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting input stream configuration for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Get input channel information.
+  nStreams = bufferList->mNumberBuffers;
+  for ( i=0; i<nStreams; i++ )
+    info.inputChannels += bufferList->mBuffers[i].mNumberChannels;
+  free( bufferList );
+
+  // If device opens for both playback and capture, we determine the channels.
+  if ( info.outputChannels > 0 && info.inputChannels > 0 )
+    info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+
+  // Probe the device sample rates.
+  bool isInput = false;
+  if ( info.outputChannels == 0 ) isInput = true;
+
+  // Determine the supported sample rates.
+  property.mSelector = kAudioDevicePropertyAvailableNominalSampleRates;
+  if ( isInput == false ) property.mScope = kAudioDevicePropertyScopeOutput;
+  result = AudioObjectGetPropertyDataSize( id, &property, 0, NULL, &dataSize );
+  if ( result != kAudioHardwareNoError || dataSize == 0 ) {
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting sample rate info.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  UInt32 nRanges = dataSize / sizeof( AudioValueRange );
+  AudioValueRange rangeList[ nRanges ];
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &rangeList );
+  if ( result != kAudioHardwareNoError ) {
+    errorStream_ << "RtApiCore::getDeviceInfo: system error (" << getErrorCode( result ) << ") getting sample rates.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // The sample rate reporting mechanism is a bit of a mystery.  It
+  // seems that it can either return individual rates or a range of
+  // rates.  I assume that if the min / max range values are the same,
+  // then that represents a single supported rate and if the min / max
+  // range values are different, the device supports an arbitrary
+  // range of values (though there might be multiple ranges, so we'll
+  // use the most conservative range).
+  Float64 minimumRate = 1.0, maximumRate = 10000000000.0;
+  bool haveValueRange = false;
+  info.sampleRates.clear();
+  for ( UInt32 i=0; i<nRanges; i++ ) {
+    if ( rangeList[i].mMinimum == rangeList[i].mMaximum ) {
+      unsigned int tmpSr = (unsigned int) rangeList[i].mMinimum;
+      info.sampleRates.push_back( tmpSr );
+
+      if ( !info.preferredSampleRate || ( tmpSr <= 48000 && tmpSr > info.preferredSampleRate ) )
+        info.preferredSampleRate = tmpSr;
+
+    } else {
+      haveValueRange = true;
+      if ( rangeList[i].mMinimum > minimumRate ) minimumRate = rangeList[i].mMinimum;
+      if ( rangeList[i].mMaximum < maximumRate ) maximumRate = rangeList[i].mMaximum;
+    }
+  }
+
+  if ( haveValueRange ) {
+    for ( unsigned int k=0; k<MAX_SAMPLE_RATES; k++ ) {
+      if ( SAMPLE_RATES[k] >= (unsigned int) minimumRate && SAMPLE_RATES[k] <= (unsigned int) maximumRate ) {
+        info.sampleRates.push_back( SAMPLE_RATES[k] );
+
+        if ( !info.preferredSampleRate || ( SAMPLE_RATES[k] <= 48000 && SAMPLE_RATES[k] > info.preferredSampleRate ) )
+          info.preferredSampleRate = SAMPLE_RATES[k];
+      }
+    }
+  }
+
+  // Sort and remove any redundant values
+  std::sort( info.sampleRates.begin(), info.sampleRates.end() );
+  info.sampleRates.erase( unique( info.sampleRates.begin(), info.sampleRates.end() ), info.sampleRates.end() );
+
+  if ( info.sampleRates.size() == 0 ) {
+    errorStream_ << "RtApiCore::probeDeviceInfo: No supported sample rates found for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // CoreAudio always uses 32-bit floating point data for PCM streams.
+  // Thus, any other "physical" formats supported by the device are of
+  // no interest to the client.
+  info.nativeFormats = RTAUDIO_FLOAT32;
+
+  if ( info.outputChannels > 0 )
+    if ( getDefaultOutputDevice() == device ) info.isDefaultOutput = true;
+  if ( info.inputChannels > 0 )
+    if ( getDefaultInputDevice() == device ) info.isDefaultInput = true;
+
+  info.probed = true;
+  return info;
+}
+
+static OSStatus callbackHandler( AudioDeviceID inDevice,
+                                 const AudioTimeStamp* /*inNow*/,
+                                 const AudioBufferList* inInputData,
+                                 const AudioTimeStamp* /*inInputTime*/,
+                                 AudioBufferList* outOutputData,
+                                 const AudioTimeStamp* /*inOutputTime*/,
+                                 void* infoPointer )
+{
+  CallbackInfo *info = (CallbackInfo *) infoPointer;
+
+  RtApiCore *object = (RtApiCore *) info->object;
+  if ( object->callbackEvent( inDevice, inInputData, outOutputData ) == false )
+    return kAudioHardwareUnspecifiedError;
+  else
+    return kAudioHardwareNoError;
+}
+
+static OSStatus xrunListener( AudioObjectID /*inDevice*/,
+                              UInt32 nAddresses,
+                              const AudioObjectPropertyAddress properties[],
+                              void* handlePointer )
+{
+  CoreHandle *handle = (CoreHandle *) handlePointer;
+  for ( UInt32 i=0; i<nAddresses; i++ ) {
+    if ( properties[i].mSelector == kAudioDeviceProcessorOverload ) {
+      if ( properties[i].mScope == kAudioDevicePropertyScopeInput )
+        handle->xrun[1] = true;
+      else
+        handle->xrun[0] = true;
+    }
+  }
+
+  return kAudioHardwareNoError;
+}
+
+static OSStatus rateListener( AudioObjectID inDevice,
+                              UInt32 /*nAddresses*/,
+                              const AudioObjectPropertyAddress /*properties*/[],
+                              void* ratePointer )
+{
+  Float64 *rate = (Float64 *) ratePointer;
+  UInt32 dataSize = sizeof( Float64 );
+  AudioObjectPropertyAddress property = { kAudioDevicePropertyNominalSampleRate,
+                                          kAudioObjectPropertyScopeGlobal,
+                                          kAudioObjectPropertyElementMaster };
+  AudioObjectGetPropertyData( inDevice, &property, 0, NULL, &dataSize, rate );
+  return kAudioHardwareNoError;
+}
+
+bool RtApiCore :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                   unsigned int firstChannel, unsigned int sampleRate,
+                                   RtAudioFormat format, unsigned int *bufferSize,
+                                   RtAudio::StreamOptions *options )
+{
+  // Get device ID
+  unsigned int nDevices = getDeviceCount();
+  if ( nDevices == 0 ) {
+    // This should not happen because a check is made before this function is called.
+    errorText_ = "RtApiCore::probeDeviceOpen: no devices found!";
+    return FAILURE;
+  }
+
+  if ( device >= nDevices ) {
+    // This should not happen because a check is made before this function is called.
+    errorText_ = "RtApiCore::probeDeviceOpen: device ID is invalid!";
+    return FAILURE;
+  }
+
+  AudioDeviceID deviceList[ nDevices ];
+  UInt32 dataSize = sizeof( AudioDeviceID ) * nDevices;
+  AudioObjectPropertyAddress property = { kAudioHardwarePropertyDevices,
+                                          kAudioObjectPropertyScopeGlobal,
+                                          kAudioObjectPropertyElementMaster };
+  OSStatus result = AudioObjectGetPropertyData( kAudioObjectSystemObject, &property,
+                                                0, NULL, &dataSize, (void *) &deviceList );
+  if ( result != noErr ) {
+    errorText_ = "RtApiCore::probeDeviceOpen: OS-X system error getting device IDs.";
+    return FAILURE;
+  }
+
+  AudioDeviceID id = deviceList[ device ];
+
+  // Setup for stream mode.
+  bool isInput = false;
+  if ( mode == INPUT ) {
+    isInput = true;
+    property.mScope = kAudioDevicePropertyScopeInput;
+  }
+  else
+    property.mScope = kAudioDevicePropertyScopeOutput;
+
+  // Get the stream "configuration".
+  AudioBufferList	*bufferList = nil;
+  dataSize = 0;
+  property.mSelector = kAudioDevicePropertyStreamConfiguration;
+  result = AudioObjectGetPropertyDataSize( id, &property, 0, NULL, &dataSize );
+  if ( result != noErr || dataSize == 0 ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting stream configuration info for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Allocate the AudioBufferList.
+  bufferList = (AudioBufferList *) malloc( dataSize );
+  if ( bufferList == NULL ) {
+    errorText_ = "RtApiCore::probeDeviceOpen: memory error allocating AudioBufferList.";
+    return FAILURE;
+  }
+
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, bufferList );
+  if (result != noErr || dataSize == 0) {
+    free( bufferList );
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting stream configuration for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Search for one or more streams that contain the desired number of
+  // channels. CoreAudio devices can have an arbitrary number of
+  // streams and each stream can have an arbitrary number of channels.
+  // For each stream, a single buffer of interleaved samples is
+  // provided.  RtAudio prefers the use of one stream of interleaved
+  // data or multiple consecutive single-channel streams.  However, we
+  // now support multiple consecutive multi-channel streams of
+  // interleaved data as well.
+  UInt32 iStream, offsetCounter = firstChannel;
+  UInt32 nStreams = bufferList->mNumberBuffers;
+  bool monoMode = false;
+  bool foundStream = false;
+
+  // First check that the device supports the requested number of
+  // channels.
+  UInt32 deviceChannels = 0;
+  for ( iStream=0; iStream<nStreams; iStream++ )
+    deviceChannels += bufferList->mBuffers[iStream].mNumberChannels;
+
+  if ( deviceChannels < ( channels + firstChannel ) ) {
+    free( bufferList );
+    errorStream_ << "RtApiCore::probeDeviceOpen: the device (" << device << ") does not support the requested channel count.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Look for a single stream meeting our needs.
+  UInt32 firstStream, streamCount = 1, streamChannels = 0, channelOffset = 0;
+  for ( iStream=0; iStream<nStreams; iStream++ ) {
+    streamChannels = bufferList->mBuffers[iStream].mNumberChannels;
+    if ( streamChannels >= channels + offsetCounter ) {
+      firstStream = iStream;
+      channelOffset = offsetCounter;
+      foundStream = true;
+      break;
+    }
+    if ( streamChannels > offsetCounter ) break;
+    offsetCounter -= streamChannels;
+  }
+
+  // If we didn't find a single stream above, then we should be able
+  // to meet the channel specification with multiple streams.
+  if ( foundStream == false ) {
+    monoMode = true;
+    offsetCounter = firstChannel;
+    for ( iStream=0; iStream<nStreams; iStream++ ) {
+      streamChannels = bufferList->mBuffers[iStream].mNumberChannels;
+      if ( streamChannels > offsetCounter ) break;
+      offsetCounter -= streamChannels;
+    }
+
+    firstStream = iStream;
+    channelOffset = offsetCounter;
+    Int32 channelCounter = channels + offsetCounter - streamChannels;
+
+    if ( streamChannels > 1 ) monoMode = false;
+    while ( channelCounter > 0 ) {
+      streamChannels = bufferList->mBuffers[++iStream].mNumberChannels;
+      if ( streamChannels > 1 ) monoMode = false;
+      channelCounter -= streamChannels;
+      streamCount++;
+    }
+  }
+
+  free( bufferList );
+
+  // Determine the buffer size.
+  AudioValueRange	bufferRange;
+  dataSize = sizeof( AudioValueRange );
+  property.mSelector = kAudioDevicePropertyBufferFrameSizeRange;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &bufferRange );
+
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting buffer size range for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  if ( bufferRange.mMinimum > *bufferSize ) *bufferSize = (unsigned long) bufferRange.mMinimum;
+  else if ( bufferRange.mMaximum < *bufferSize ) *bufferSize = (unsigned long) bufferRange.mMaximum;
+  if ( options && options->flags & RTAUDIO_MINIMIZE_LATENCY ) *bufferSize = (unsigned long) bufferRange.mMinimum;
+
+  // Set the buffer size.  For multiple streams, I'm assuming we only
+  // need to make this setting for the master channel.
+  UInt32 theSize = (UInt32) *bufferSize;
+  dataSize = sizeof( UInt32 );
+  property.mSelector = kAudioDevicePropertyBufferFrameSize;
+  result = AudioObjectSetPropertyData( id, &property, 0, NULL, dataSize, &theSize );
+
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting the buffer size for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // If attempting to setup a duplex stream, the bufferSize parameter
+  // MUST be the same in both directions!
+  *bufferSize = theSize;
+  if ( stream_.mode == OUTPUT && mode == INPUT && *bufferSize != stream_.bufferSize ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error setting buffer size for duplex stream on device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  stream_.bufferSize = *bufferSize;
+  stream_.nBuffers = 1;
+
+  // Try to set "hog" mode ... it's not clear to me this is working.
+  if ( options && options->flags & RTAUDIO_HOG_DEVICE ) {
+    pid_t hog_pid;
+    dataSize = sizeof( hog_pid );
+    property.mSelector = kAudioDevicePropertyHogMode;
+    result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &hog_pid );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting 'hog' state!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    if ( hog_pid != getpid() ) {
+      hog_pid = getpid();
+      result = AudioObjectSetPropertyData( id, &property, 0, NULL, dataSize, &hog_pid );
+      if ( result != noErr ) {
+        errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting 'hog' state!";
+        errorText_ = errorStream_.str();
+        return FAILURE;
+      }
+    }
+  }
+
+  // Check and if necessary, change the sample rate for the device.
+  Float64 nominalRate;
+  dataSize = sizeof( Float64 );
+  property.mSelector = kAudioDevicePropertyNominalSampleRate;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &nominalRate );
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting current sample rate.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Only change the sample rate if off by more than 1 Hz.
+  if ( fabs( nominalRate - (double)sampleRate ) > 1.0 ) {
+
+    // Set a property listener for the sample rate change
+    Float64 reportedRate = 0.0;
+    AudioObjectPropertyAddress tmp = { kAudioDevicePropertyNominalSampleRate, kAudioObjectPropertyScopeGlobal, kAudioObjectPropertyElementMaster };
+    result = AudioObjectAddPropertyListener( id, &tmp, rateListener, (void *) &reportedRate );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting sample rate property listener for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    nominalRate = (Float64) sampleRate;
+    result = AudioObjectSetPropertyData( id, &property, 0, NULL, dataSize, &nominalRate );
+    if ( result != noErr ) {
+      AudioObjectRemovePropertyListener( id, &tmp, rateListener, (void *) &reportedRate );
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting sample rate for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Now wait until the reported nominal rate is what we just set.
+    UInt32 microCounter = 0;
+    while ( reportedRate != nominalRate ) {
+      microCounter += 5000;
+      if ( microCounter > 5000000 ) break;
+      usleep( 5000 );
+    }
+
+    // Remove the property listener.
+    AudioObjectRemovePropertyListener( id, &tmp, rateListener, (void *) &reportedRate );
+
+    if ( microCounter > 5000000 ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: timeout waiting for sample rate update for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+
+  // Now set the stream format for all streams.  Also, check the
+  // physical format of the device and change that if necessary.
+  AudioStreamBasicDescription	description;
+  dataSize = sizeof( AudioStreamBasicDescription );
+  property.mSelector = kAudioStreamPropertyVirtualFormat;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &description );
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting stream format for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Set the sample rate and data format id.  However, only make the
+  // change if the sample rate is not within 1.0 of the desired
+  // rate and the format is not linear pcm.
+  bool updateFormat = false;
+  if ( fabs( description.mSampleRate - (Float64)sampleRate ) > 1.0 ) {
+    description.mSampleRate = (Float64) sampleRate;
+    updateFormat = true;
+  }
+
+  if ( description.mFormatID != kAudioFormatLinearPCM ) {
+    description.mFormatID = kAudioFormatLinearPCM;
+    updateFormat = true;
+  }
+
+  if ( updateFormat ) {
+    result = AudioObjectSetPropertyData( id, &property, 0, NULL, dataSize, &description );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting sample rate or data format for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+
+  // Now check the physical format.
+  property.mSelector = kAudioStreamPropertyPhysicalFormat;
+  result = AudioObjectGetPropertyData( id, &property, 0, NULL,  &dataSize, &description );
+  if ( result != noErr ) {
+    errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting stream physical format for device (" << device << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  //std::cout << "Current physical stream format:" << std::endl;
+  //std::cout << "   mBitsPerChan = " << description.mBitsPerChannel << std::endl;
+  //std::cout << "   aligned high = " << (description.mFormatFlags & kAudioFormatFlagIsAlignedHigh) << ", isPacked = " << (description.mFormatFlags & kAudioFormatFlagIsPacked) << std::endl;
+  //std::cout << "   bytesPerFrame = " << description.mBytesPerFrame << std::endl;
+  //std::cout << "   sample rate = " << description.mSampleRate << std::endl;
+
+  if ( description.mFormatID != kAudioFormatLinearPCM || description.mBitsPerChannel < 16 ) {
+    description.mFormatID = kAudioFormatLinearPCM;
+    //description.mSampleRate = (Float64) sampleRate;
+    AudioStreamBasicDescription	testDescription = description;
+    UInt32 formatFlags;
+
+    // We'll try higher bit rates first and then work our way down.
+    std::vector< std::pair<UInt32, UInt32>  > physicalFormats;
+    formatFlags = (description.mFormatFlags | kLinearPCMFormatFlagIsFloat) & ~kLinearPCMFormatFlagIsSignedInteger;
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 32, formatFlags ) );
+    formatFlags = (description.mFormatFlags | kLinearPCMFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked) & ~kLinearPCMFormatFlagIsFloat;
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 32, formatFlags ) );
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 24, formatFlags ) );   // 24-bit packed
+    formatFlags &= ~( kAudioFormatFlagIsPacked | kAudioFormatFlagIsAlignedHigh );
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 24.2, formatFlags ) ); // 24-bit in 4 bytes, aligned low
+    formatFlags |= kAudioFormatFlagIsAlignedHigh;
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 24.4, formatFlags ) ); // 24-bit in 4 bytes, aligned high
+    formatFlags = (description.mFormatFlags | kLinearPCMFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked) & ~kLinearPCMFormatFlagIsFloat;
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 16, formatFlags ) );
+    physicalFormats.push_back( std::pair<Float32, UInt32>( 8, formatFlags ) );
+
+    bool setPhysicalFormat = false;
+    for( unsigned int i=0; i<physicalFormats.size(); i++ ) {
+      testDescription = description;
+      testDescription.mBitsPerChannel = (UInt32) physicalFormats[i].first;
+      testDescription.mFormatFlags = physicalFormats[i].second;
+      if ( (24 == (UInt32)physicalFormats[i].first) && ~( physicalFormats[i].second & kAudioFormatFlagIsPacked ) )
+        testDescription.mBytesPerFrame =  4 * testDescription.mChannelsPerFrame;
+      else
+        testDescription.mBytesPerFrame =  testDescription.mBitsPerChannel/8 * testDescription.mChannelsPerFrame;
+      testDescription.mBytesPerPacket = testDescription.mBytesPerFrame * testDescription.mFramesPerPacket;
+      result = AudioObjectSetPropertyData( id, &property, 0, NULL, dataSize, &testDescription );
+      if ( result == noErr ) {
+        setPhysicalFormat = true;
+        //std::cout << "Updated physical stream format:" << std::endl;
+        //std::cout << "   mBitsPerChan = " << testDescription.mBitsPerChannel << std::endl;
+        //std::cout << "   aligned high = " << (testDescription.mFormatFlags & kAudioFormatFlagIsAlignedHigh) << ", isPacked = " << (testDescription.mFormatFlags & kAudioFormatFlagIsPacked) << std::endl;
+        //std::cout << "   bytesPerFrame = " << testDescription.mBytesPerFrame << std::endl;
+        //std::cout << "   sample rate = " << testDescription.mSampleRate << std::endl;
+        break;
+      }
+    }
+
+    if ( !setPhysicalFormat ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") setting physical data format for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  } // done setting virtual/physical formats.
+
+  // Get the stream / device latency.
+  UInt32 latency;
+  dataSize = sizeof( UInt32 );
+  property.mSelector = kAudioDevicePropertyLatency;
+  if ( AudioObjectHasProperty( id, &property ) == true ) {
+    result = AudioObjectGetPropertyData( id, &property, 0, NULL, &dataSize, &latency );
+    if ( result == kAudioHardwareNoError ) stream_.latency[ mode ] = latency;
+    else {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error (" << getErrorCode( result ) << ") getting device latency for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      error( RtAudioError::WARNING );
+    }
+  }
+
+  // Byte-swapping: According to AudioHardware.h, the stream data will
+  // always be presented in native-endian format, so we should never
+  // need to byte swap.
+  stream_.doByteSwap[mode] = false;
+
+  // From the CoreAudio documentation, PCM data must be supplied as
+  // 32-bit floats.
+  stream_.userFormat = format;
+  stream_.deviceFormat[mode] = RTAUDIO_FLOAT32;
+
+  if ( streamCount == 1 )
+    stream_.nDeviceChannels[mode] = description.mChannelsPerFrame;
+  else // multiple streams
+    stream_.nDeviceChannels[mode] = channels;
+  stream_.nUserChannels[mode] = channels;
+  stream_.channelOffset[mode] = channelOffset;  // offset within a CoreAudio stream
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) stream_.userInterleaved = false;
+  else stream_.userInterleaved = true;
+  stream_.deviceInterleaved[mode] = true;
+  if ( monoMode == true ) stream_.deviceInterleaved[mode] = false;
+
+  // Set flags for buffer conversion.
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.nUserChannels[mode] < stream_.nDeviceChannels[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( streamCount == 1 ) {
+    if ( stream_.nUserChannels[mode] > 1 &&
+         stream_.userInterleaved != stream_.deviceInterleaved[mode] )
+      stream_.doConvertBuffer[mode] = true;
+  }
+  else if ( monoMode && stream_.userInterleaved )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate our CoreHandle structure for the stream.
+  CoreHandle *handle = 0;
+  if ( stream_.apiHandle == 0 ) {
+    try {
+      handle = new CoreHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiCore::probeDeviceOpen: error allocating CoreHandle memory.";
+      goto error;
+    }
+
+    if ( pthread_cond_init( &handle->condition, NULL ) ) {
+      errorText_ = "RtApiCore::probeDeviceOpen: error initializing pthread condition variable.";
+      goto error;
+    }
+    stream_.apiHandle = (void *) handle;
+  }
+  else
+    handle = (CoreHandle *) stream_.apiHandle;
+  handle->iStream[mode] = firstStream;
+  handle->nStreams[mode] = streamCount;
+  handle->id[mode] = id;
+
+  // Allocate necessary internal buffers.
+  unsigned long bufferBytes;
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  //  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  stream_.userBuffer[mode] = (char *) malloc( bufferBytes * sizeof(char) );
+  memset( stream_.userBuffer[mode], 0, bufferBytes * sizeof(char) );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiCore::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  // If possible, we will make use of the CoreAudio stream buffers as
+  // "device buffers".  However, we can't do this if using multiple
+  // streams.
+  if ( stream_.doConvertBuffer[mode] && handle->nStreams[mode] > 1 ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( mode == INPUT ) {
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+        if ( bufferBytes <= bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiCore::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  stream_.sampleRate = sampleRate;
+  stream_.device[mode] = device;
+  stream_.state = STREAM_STOPPED;
+  stream_.callbackInfo.object = (void *) this;
+
+  // Setup the buffer conversion information structure.
+  if ( stream_.doConvertBuffer[mode] ) {
+    if ( streamCount > 1 ) setConvertInfo( mode, 0 );
+    else setConvertInfo( mode, channelOffset );
+  }
+
+  if ( mode == INPUT && stream_.mode == OUTPUT && stream_.device[0] == device )
+    // Only one callback procedure per device.
+    stream_.mode = DUPLEX;
+  else {
+#if defined( MAC_OS_X_VERSION_10_5 ) && ( MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_5 )
+    result = AudioDeviceCreateIOProcID( id, callbackHandler, (void *) &stream_.callbackInfo, &handle->procId[mode] );
+#else
+    // deprecated in favor of AudioDeviceCreateIOProcID()
+    result = AudioDeviceAddIOProc( id, callbackHandler, (void *) &stream_.callbackInfo );
+#endif
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::probeDeviceOpen: system error setting callback for device (" << device << ").";
+      errorText_ = errorStream_.str();
+      goto error;
+    }
+    if ( stream_.mode == OUTPUT && mode == INPUT )
+      stream_.mode = DUPLEX;
+    else
+      stream_.mode = mode;
+  }
+
+  // Setup the device property listener for over/underload.
+  property.mSelector = kAudioDeviceProcessorOverload;
+  property.mScope = kAudioObjectPropertyScopeGlobal;
+  result = AudioObjectAddPropertyListener( id, &property, xrunListener, (void *) handle );
+
+  return SUCCESS;
+
+ error:
+  if ( handle ) {
+    pthread_cond_destroy( &handle->condition );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.state = STREAM_CLOSED;
+  return FAILURE;
+}
+
+void RtApiCore :: closeStream( void )
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiCore::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  CoreHandle *handle = (CoreHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    if (handle) {
+      AudioObjectPropertyAddress property = { kAudioHardwarePropertyDevices,
+        kAudioObjectPropertyScopeGlobal,
+        kAudioObjectPropertyElementMaster };
+
+      property.mSelector = kAudioDeviceProcessorOverload;
+      property.mScope = kAudioObjectPropertyScopeGlobal;
+      if (AudioObjectRemovePropertyListener( handle->id[0], &property, xrunListener, (void *) handle ) != noErr) {
+        errorText_ = "RtApiCore::closeStream(): error removing property listener!";
+        error( RtAudioError::WARNING );
+      }
+    }
+    if ( stream_.state == STREAM_RUNNING )
+      AudioDeviceStop( handle->id[0], callbackHandler );
+#if defined( MAC_OS_X_VERSION_10_5 ) && ( MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_5 )
+    AudioDeviceDestroyIOProcID( handle->id[0], handle->procId[0] );
+#else
+    // deprecated in favor of AudioDeviceDestroyIOProcID()
+    AudioDeviceRemoveIOProc( handle->id[0], callbackHandler );
+#endif
+  }
+
+  if ( stream_.mode == INPUT || ( stream_.mode == DUPLEX && stream_.device[0] != stream_.device[1] ) ) {
+    if (handle) {
+      AudioObjectPropertyAddress property = { kAudioHardwarePropertyDevices,
+        kAudioObjectPropertyScopeGlobal,
+        kAudioObjectPropertyElementMaster };
+
+      property.mSelector = kAudioDeviceProcessorOverload;
+      property.mScope = kAudioObjectPropertyScopeGlobal;
+      if (AudioObjectRemovePropertyListener( handle->id[1], &property, xrunListener, (void *) handle ) != noErr) {
+        errorText_ = "RtApiCore::closeStream(): error removing property listener!";
+        error( RtAudioError::WARNING );
+      }
+    }
+    if ( stream_.state == STREAM_RUNNING )
+      AudioDeviceStop( handle->id[1], callbackHandler );
+#if defined( MAC_OS_X_VERSION_10_5 ) && ( MAC_OS_X_VERSION_MIN_REQUIRED >= MAC_OS_X_VERSION_10_5 )
+    AudioDeviceDestroyIOProcID( handle->id[1], handle->procId[1] );
+#else
+    // deprecated in favor of AudioDeviceDestroyIOProcID()
+    AudioDeviceRemoveIOProc( handle->id[1], callbackHandler );
+#endif
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  // Destroy pthread condition variable.
+  pthread_cond_destroy( &handle->condition );
+  delete handle;
+  stream_.apiHandle = 0;
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+void RtApiCore :: startStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiCore::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  OSStatus result = noErr;
+  CoreHandle *handle = (CoreHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    result = AudioDeviceStart( handle->id[0], callbackHandler );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::startStream: system error (" << getErrorCode( result ) << ") starting callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  if ( stream_.mode == INPUT ||
+       ( stream_.mode == DUPLEX && stream_.device[0] != stream_.device[1] ) ) {
+
+    result = AudioDeviceStart( handle->id[1], callbackHandler );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::startStream: system error starting input callback procedure on device (" << stream_.device[1] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  handle->drainCounter = 0;
+  handle->internalDrain = false;
+  stream_.state = STREAM_RUNNING;
+
+ unlock:
+  if ( result == noErr ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiCore :: stopStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiCore::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  OSStatus result = noErr;
+  CoreHandle *handle = (CoreHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    if ( handle->drainCounter == 0 ) {
+      handle->drainCounter = 2;
+      pthread_cond_wait( &handle->condition, &stream_.mutex ); // block until signaled
+    }
+
+    result = AudioDeviceStop( handle->id[0], callbackHandler );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::stopStream: system error (" << getErrorCode( result ) << ") stopping callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  if ( stream_.mode == INPUT || ( stream_.mode == DUPLEX && stream_.device[0] != stream_.device[1] ) ) {
+
+    result = AudioDeviceStop( handle->id[1], callbackHandler );
+    if ( result != noErr ) {
+      errorStream_ << "RtApiCore::stopStream: system error (" << getErrorCode( result ) << ") stopping input callback procedure on device (" << stream_.device[1] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  stream_.state = STREAM_STOPPED;
+
+ unlock:
+  if ( result == noErr ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiCore :: abortStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiCore::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  CoreHandle *handle = (CoreHandle *) stream_.apiHandle;
+  handle->drainCounter = 2;
+
+  stopStream();
+}
+
+// This function will be called by a spawned thread when the user
+// callback function signals that the stream should be stopped or
+// aborted.  It is better to handle it this way because the
+// callbackEvent() function probably should return before the AudioDeviceStop()
+// function is called.
+static void *coreStopStream( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiCore *object = (RtApiCore *) info->object;
+
+  object->stopStream();
+  pthread_exit( NULL );
+}
+
+bool RtApiCore :: callbackEvent( AudioDeviceID deviceId,
+                                 const AudioBufferList *inBufferList,
+                                 const AudioBufferList *outBufferList )
+{
+  if ( stream_.state == STREAM_STOPPED || stream_.state == STREAM_STOPPING ) return SUCCESS;
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiCore::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return FAILURE;
+  }
+
+  CallbackInfo *info = (CallbackInfo *) &stream_.callbackInfo;
+  CoreHandle *handle = (CoreHandle *) stream_.apiHandle;
+
+  // Check if we were draining the stream and signal is finished.
+  if ( handle->drainCounter > 3 ) {
+    ThreadHandle threadId;
+
+    stream_.state = STREAM_STOPPING;
+    if ( handle->internalDrain == true )
+      pthread_create( &threadId, NULL, coreStopStream, info );
+    else // external call to stopStream()
+      pthread_cond_signal( &handle->condition );
+    return SUCCESS;
+  }
+
+  AudioDeviceID outputDevice = handle->id[0];
+
+  // Invoke user callback to get fresh output data UNLESS we are
+  // draining stream or duplex mode AND the input/output devices are
+  // different AND this function is called for the input device.
+  if ( handle->drainCounter == 0 && ( stream_.mode != DUPLEX || deviceId == outputDevice ) ) {
+    RtAudioCallback callback = (RtAudioCallback) info->callback;
+    double streamTime = getStreamTime();
+    RtAudioStreamStatus status = 0;
+    if ( stream_.mode != INPUT && handle->xrun[0] == true ) {
+      status |= RTAUDIO_OUTPUT_UNDERFLOW;
+      handle->xrun[0] = false;
+    }
+    if ( stream_.mode != OUTPUT && handle->xrun[1] == true ) {
+      status |= RTAUDIO_INPUT_OVERFLOW;
+      handle->xrun[1] = false;
+    }
+
+    int cbReturnValue = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                                  stream_.bufferSize, streamTime, status, info->userData );
+    if ( cbReturnValue == 2 ) {
+      stream_.state = STREAM_STOPPING;
+      handle->drainCounter = 2;
+      abortStream();
+      return SUCCESS;
+    }
+    else if ( cbReturnValue == 1 ) {
+      handle->drainCounter = 1;
+      handle->internalDrain = true;
+    }
+  }
+
+  if ( stream_.mode == OUTPUT || ( stream_.mode == DUPLEX && deviceId == outputDevice ) ) {
+
+    if ( handle->drainCounter > 1 ) { // write zeros to the output stream
+
+      if ( handle->nStreams[0] == 1 ) {
+        memset( outBufferList->mBuffers[handle->iStream[0]].mData,
+                0,
+                outBufferList->mBuffers[handle->iStream[0]].mDataByteSize );
+      }
+      else { // fill multiple streams with zeros
+        for ( unsigned int i=0; i<handle->nStreams[0]; i++ ) {
+          memset( outBufferList->mBuffers[handle->iStream[0]+i].mData,
+                  0,
+                  outBufferList->mBuffers[handle->iStream[0]+i].mDataByteSize );
+        }
+      }
+    }
+    else if ( handle->nStreams[0] == 1 ) {
+      if ( stream_.doConvertBuffer[0] ) { // convert directly to CoreAudio stream buffer
+        convertBuffer( (char *) outBufferList->mBuffers[handle->iStream[0]].mData,
+                       stream_.userBuffer[0], stream_.convertInfo[0] );
+      }
+      else { // copy from user buffer
+        memcpy( outBufferList->mBuffers[handle->iStream[0]].mData,
+                stream_.userBuffer[0],
+                outBufferList->mBuffers[handle->iStream[0]].mDataByteSize );
+      }
+    }
+    else { // fill multiple streams
+      Float32 *inBuffer = (Float32 *) stream_.userBuffer[0];
+      if ( stream_.doConvertBuffer[0] ) {
+        convertBuffer( stream_.deviceBuffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+        inBuffer = (Float32 *) stream_.deviceBuffer;
+      }
+
+      if ( stream_.deviceInterleaved[0] == false ) { // mono mode
+        UInt32 bufferBytes = outBufferList->mBuffers[handle->iStream[0]].mDataByteSize;
+        for ( unsigned int i=0; i<stream_.nUserChannels[0]; i++ ) {
+          memcpy( outBufferList->mBuffers[handle->iStream[0]+i].mData,
+                  (void *)&inBuffer[i*stream_.bufferSize], bufferBytes );
+        }
+      }
+      else { // fill multiple multi-channel streams with interleaved data
+        UInt32 streamChannels, channelsLeft, inJump, outJump, inOffset;
+        Float32 *out, *in;
+
+        bool inInterleaved = ( stream_.userInterleaved ) ? true : false;
+        UInt32 inChannels = stream_.nUserChannels[0];
+        if ( stream_.doConvertBuffer[0] ) {
+          inInterleaved = true; // device buffer will always be interleaved for nStreams > 1 and not mono mode
+          inChannels = stream_.nDeviceChannels[0];
+        }
+
+        if ( inInterleaved ) inOffset = 1;
+        else inOffset = stream_.bufferSize;
+
+        channelsLeft = inChannels;
+        for ( unsigned int i=0; i<handle->nStreams[0]; i++ ) {
+          in = inBuffer;
+          out = (Float32 *) outBufferList->mBuffers[handle->iStream[0]+i].mData;
+          streamChannels = outBufferList->mBuffers[handle->iStream[0]+i].mNumberChannels;
+
+          outJump = 0;
+          // Account for possible channel offset in first stream
+          if ( i == 0 && stream_.channelOffset[0] > 0 ) {
+            streamChannels -= stream_.channelOffset[0];
+            outJump = stream_.channelOffset[0];
+            out += outJump;
+          }
+
+          // Account for possible unfilled channels at end of the last stream
+          if ( streamChannels > channelsLeft ) {
+            outJump = streamChannels - channelsLeft;
+            streamChannels = channelsLeft;
+          }
+
+          // Determine input buffer offsets and skips
+          if ( inInterleaved ) {
+            inJump = inChannels;
+            in += inChannels - channelsLeft;
+          }
+          else {
+            inJump = 1;
+            in += (inChannels - channelsLeft) * inOffset;
+          }
+
+          for ( unsigned int i=0; i<stream_.bufferSize; i++ ) {
+            for ( unsigned int j=0; j<streamChannels; j++ ) {
+              *out++ = in[j*inOffset];
+            }
+            out += outJump;
+            in += inJump;
+          }
+          channelsLeft -= streamChannels;
+        }
+      }
+    }
+  }
+
+  // Don't bother draining input
+  if ( handle->drainCounter ) {
+    handle->drainCounter++;
+    goto unlock;
+  }
+
+  AudioDeviceID inputDevice;
+  inputDevice = handle->id[1];
+  if ( stream_.mode == INPUT || ( stream_.mode == DUPLEX && deviceId == inputDevice ) ) {
+
+    if ( handle->nStreams[1] == 1 ) {
+      if ( stream_.doConvertBuffer[1] ) { // convert directly from CoreAudio stream buffer
+        convertBuffer( stream_.userBuffer[1],
+                       (char *) inBufferList->mBuffers[handle->iStream[1]].mData,
+                       stream_.convertInfo[1] );
+      }
+      else { // copy to user buffer
+        memcpy( stream_.userBuffer[1],
+                inBufferList->mBuffers[handle->iStream[1]].mData,
+                inBufferList->mBuffers[handle->iStream[1]].mDataByteSize );
+      }
+    }
+    else { // read from multiple streams
+      Float32 *outBuffer = (Float32 *) stream_.userBuffer[1];
+      if ( stream_.doConvertBuffer[1] ) outBuffer = (Float32 *) stream_.deviceBuffer;
+
+      if ( stream_.deviceInterleaved[1] == false ) { // mono mode
+        UInt32 bufferBytes = inBufferList->mBuffers[handle->iStream[1]].mDataByteSize;
+        for ( unsigned int i=0; i<stream_.nUserChannels[1]; i++ ) {
+          memcpy( (void *)&outBuffer[i*stream_.bufferSize],
+                  inBufferList->mBuffers[handle->iStream[1]+i].mData, bufferBytes );
+        }
+      }
+      else { // read from multiple multi-channel streams
+        UInt32 streamChannels, channelsLeft, inJump, outJump, outOffset;
+        Float32 *out, *in;
+
+        bool outInterleaved = ( stream_.userInterleaved ) ? true : false;
+        UInt32 outChannels = stream_.nUserChannels[1];
+        if ( stream_.doConvertBuffer[1] ) {
+          outInterleaved = true; // device buffer will always be interleaved for nStreams > 1 and not mono mode
+          outChannels = stream_.nDeviceChannels[1];
+        }
+
+        if ( outInterleaved ) outOffset = 1;
+        else outOffset = stream_.bufferSize;
+
+        channelsLeft = outChannels;
+        for ( unsigned int i=0; i<handle->nStreams[1]; i++ ) {
+          out = outBuffer;
+          in = (Float32 *) inBufferList->mBuffers[handle->iStream[1]+i].mData;
+          streamChannels = inBufferList->mBuffers[handle->iStream[1]+i].mNumberChannels;
+
+          inJump = 0;
+          // Account for possible channel offset in first stream
+          if ( i == 0 && stream_.channelOffset[1] > 0 ) {
+            streamChannels -= stream_.channelOffset[1];
+            inJump = stream_.channelOffset[1];
+            in += inJump;
+          }
+
+          // Account for possible unread channels at end of the last stream
+          if ( streamChannels > channelsLeft ) {
+            inJump = streamChannels - channelsLeft;
+            streamChannels = channelsLeft;
+          }
+
+          // Determine output buffer offsets and skips
+          if ( outInterleaved ) {
+            outJump = outChannels;
+            out += outChannels - channelsLeft;
+          }
+          else {
+            outJump = 1;
+            out += (outChannels - channelsLeft) * outOffset;
+          }
+
+          for ( unsigned int i=0; i<stream_.bufferSize; i++ ) {
+            for ( unsigned int j=0; j<streamChannels; j++ ) {
+              out[j*outOffset] = *in++;
+            }
+            out += outJump;
+            in += inJump;
+          }
+          channelsLeft -= streamChannels;
+        }
+      }
+      
+      if ( stream_.doConvertBuffer[1] ) { // convert from our internal "device" buffer
+        convertBuffer( stream_.userBuffer[1],
+                       stream_.deviceBuffer,
+                       stream_.convertInfo[1] );
+      }
+    }
+  }
+
+ unlock:
+  //MUTEX_UNLOCK( &stream_.mutex );
+
+  RtApi::tickStreamTime();
+  return SUCCESS;
+}
+
+const char* RtApiCore :: getErrorCode( OSStatus code )
+{
+  switch( code ) {
+
+  case kAudioHardwareNotRunningError:
+    return "kAudioHardwareNotRunningError";
+
+  case kAudioHardwareUnspecifiedError:
+    return "kAudioHardwareUnspecifiedError";
+
+  case kAudioHardwareUnknownPropertyError:
+    return "kAudioHardwareUnknownPropertyError";
+
+  case kAudioHardwareBadPropertySizeError:
+    return "kAudioHardwareBadPropertySizeError";
+
+  case kAudioHardwareIllegalOperationError:
+    return "kAudioHardwareIllegalOperationError";
+
+  case kAudioHardwareBadObjectError:
+    return "kAudioHardwareBadObjectError";
+
+  case kAudioHardwareBadDeviceError:
+    return "kAudioHardwareBadDeviceError";
+
+  case kAudioHardwareBadStreamError:
+    return "kAudioHardwareBadStreamError";
+
+  case kAudioHardwareUnsupportedOperationError:
+    return "kAudioHardwareUnsupportedOperationError";
+
+  case kAudioDeviceUnsupportedFormatError:
+    return "kAudioDeviceUnsupportedFormatError";
+
+  case kAudioDevicePermissionsError:
+    return "kAudioDevicePermissionsError";
+
+  default:
+    return "CoreAudio unknown error";
+  }
+}
+
+  //******************** End of __MACOSX_CORE__ *********************//
+#endif
+
+#if defined(__UNIX_JACK__)
+
+// JACK is a low-latency audio server, originally written for the
+// GNU/Linux operating system and now also ported to OS-X. It can
+// connect a number of different applications to an audio device, as
+// well as allowing them to share audio between themselves.
+//
+// When using JACK with RtAudio, "devices" refer to JACK clients that
+// have ports connected to the server.  The JACK server is typically
+// started in a terminal as follows:
+//
+// .jackd -d alsa -d hw:0
+//
+// or through an interface program such as qjackctl.  Many of the
+// parameters normally set for a stream are fixed by the JACK server
+// and can be specified when the JACK server is started.  In
+// particular,
+//
+// .jackd -d alsa -d hw:0 -r 44100 -p 512 -n 4
+//
+// specifies a sample rate of 44100 Hz, a buffer size of 512 sample
+// frames, and number of buffers = 4.  Once the server is running, it
+// is not possible to override these values.  If the values are not
+// specified in the command-line, the JACK server uses default values.
+//
+// The JACK server does not have to be running when an instance of
+// RtApiJack is created, though the function getDeviceCount() will
+// report 0 devices found until JACK has been started.  When no
+// devices are available (i.e., the JACK server is not running), a
+// stream cannot be opened.
+
+#include <jack/jack.h>
+#include <unistd.h>
+#include <cstdio>
+
+// A structure to hold various information related to the Jack API
+// implementation.
+struct JackHandle {
+  jack_client_t *client;
+  jack_port_t **ports[2];
+  std::string deviceName[2];
+  bool xrun[2];
+  pthread_cond_t condition;
+  int drainCounter;       // Tracks callback counts when draining
+  bool internalDrain;     // Indicates if stop is initiated from callback or not.
+
+  JackHandle()
+    :client(0), drainCounter(0), internalDrain(false) { ports[0] = 0; ports[1] = 0; xrun[0] = false; xrun[1] = false; }
+};
+
+static void jackSilentError( const char * ) {};
+
+RtApiJack :: RtApiJack()
+{
+  // Nothing to do here.
+#if !defined(__RTAUDIO_DEBUG__)
+  // Turn off Jack's internal error reporting.
+  jack_set_error_function( &jackSilentError );
+#endif
+}
+
+RtApiJack :: ~RtApiJack()
+{
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+}
+
+unsigned int RtApiJack :: getDeviceCount( void )
+{
+  // See if we can become a jack client.
+  jack_options_t options = (jack_options_t) ( JackNoStartServer ); //JackNullOption;
+  jack_status_t *status = NULL;
+  jack_client_t *client = jack_client_open( "RtApiJackCount", options, status );
+  if ( client == 0 ) return 0;
+
+  const char **ports;
+  std::string port, previousPort;
+  unsigned int nChannels = 0, nDevices = 0;
+  ports = jack_get_ports( client, NULL, NULL, 0 );
+  if ( ports ) {
+    // Parse the port names up to the first colon (:).
+    size_t iColon = 0;
+    do {
+      port = (char *) ports[ nChannels ];
+      iColon = port.find(":");
+      if ( iColon != std::string::npos ) {
+        port = port.substr( 0, iColon + 1 );
+        if ( port != previousPort ) {
+          nDevices++;
+          previousPort = port;
+        }
+      }
+    } while ( ports[++nChannels] );
+    free( ports );
+  }
+
+  jack_client_close( client );
+  return nDevices;
+}
+
+RtAudio::DeviceInfo RtApiJack :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  jack_options_t options = (jack_options_t) ( JackNoStartServer ); //JackNullOption
+  jack_status_t *status = NULL;
+  jack_client_t *client = jack_client_open( "RtApiJackInfo", options, status );
+  if ( client == 0 ) {
+    errorText_ = "RtApiJack::getDeviceInfo: Jack server not found or connection error!";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  const char **ports;
+  std::string port, previousPort;
+  unsigned int nPorts = 0, nDevices = 0;
+  ports = jack_get_ports( client, NULL, NULL, 0 );
+  if ( ports ) {
+    // Parse the port names up to the first colon (:).
+    size_t iColon = 0;
+    do {
+      port = (char *) ports[ nPorts ];
+      iColon = port.find(":");
+      if ( iColon != std::string::npos ) {
+        port = port.substr( 0, iColon );
+        if ( port != previousPort ) {
+          if ( nDevices == device ) info.name = port;
+          nDevices++;
+          previousPort = port;
+        }
+      }
+    } while ( ports[++nPorts] );
+    free( ports );
+  }
+
+  if ( device >= nDevices ) {
+    jack_client_close( client );
+    errorText_ = "RtApiJack::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  // Get the current jack server sample rate.
+  info.sampleRates.clear();
+
+  info.preferredSampleRate = jack_get_sample_rate( client );
+  info.sampleRates.push_back( info.preferredSampleRate );
+
+  // Count the available ports containing the client name as device
+  // channels.  Jack "input ports" equal RtAudio output channels.
+  unsigned int nChannels = 0;
+  ports = jack_get_ports( client, info.name.c_str(), NULL, JackPortIsInput );
+  if ( ports ) {
+    while ( ports[ nChannels ] ) nChannels++;
+    free( ports );
+    info.outputChannels = nChannels;
+  }
+
+  // Jack "output ports" equal RtAudio input channels.
+  nChannels = 0;
+  ports = jack_get_ports( client, info.name.c_str(), NULL, JackPortIsOutput );
+  if ( ports ) {
+    while ( ports[ nChannels ] ) nChannels++;
+    free( ports );
+    info.inputChannels = nChannels;
+  }
+
+  if ( info.outputChannels == 0 && info.inputChannels == 0 ) {
+    jack_client_close(client);
+    errorText_ = "RtApiJack::getDeviceInfo: error determining Jack input/output channels!";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // If device opens for both playback and capture, we determine the channels.
+  if ( info.outputChannels > 0 && info.inputChannels > 0 )
+    info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+
+  // Jack always uses 32-bit floats.
+  info.nativeFormats = RTAUDIO_FLOAT32;
+
+  // Jack doesn't provide default devices so we'll use the first available one.
+  if ( device == 0 && info.outputChannels > 0 )
+    info.isDefaultOutput = true;
+  if ( device == 0 && info.inputChannels > 0 )
+    info.isDefaultInput = true;
+
+  jack_client_close(client);
+  info.probed = true;
+  return info;
+}
+
+static int jackCallbackHandler( jack_nframes_t nframes, void *infoPointer )
+{
+  CallbackInfo *info = (CallbackInfo *) infoPointer;
+
+  RtApiJack *object = (RtApiJack *) info->object;
+  if ( object->callbackEvent( (unsigned long) nframes ) == false ) return 1;
+
+  return 0;
+}
+
+// This function will be called by a spawned thread when the Jack
+// server signals that it is shutting down.  It is necessary to handle
+// it this way because the jackShutdown() function must return before
+// the jack_deactivate() function (in closeStream()) will return.
+static void *jackCloseStream( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiJack *object = (RtApiJack *) info->object;
+
+  object->closeStream();
+
+  pthread_exit( NULL );
+}
+static void jackShutdown( void *infoPointer )
+{
+  CallbackInfo *info = (CallbackInfo *) infoPointer;
+  RtApiJack *object = (RtApiJack *) info->object;
+
+  // Check current stream state.  If stopped, then we'll assume this
+  // was called as a result of a call to RtApiJack::stopStream (the
+  // deactivation of a client handle causes this function to be called).
+  // If not, we'll assume the Jack server is shutting down or some
+  // other problem occurred and we should close the stream.
+  if ( object->isStreamRunning() == false ) return;
+
+  ThreadHandle threadId;
+  pthread_create( &threadId, NULL, jackCloseStream, info );
+  std::cerr << "\nRtApiJack: the Jack server is shutting down this client ... stream stopped and closed!!\n" << std::endl;
+}
+
+static int jackXrun( void *infoPointer )
+{
+  JackHandle *handle = (JackHandle *) infoPointer;
+
+  if ( handle->ports[0] ) handle->xrun[0] = true;
+  if ( handle->ports[1] ) handle->xrun[1] = true;
+
+  return 0;
+}
+
+bool RtApiJack :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                   unsigned int firstChannel, unsigned int sampleRate,
+                                   RtAudioFormat format, unsigned int *bufferSize,
+                                   RtAudio::StreamOptions *options )
+{
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+
+  // Look for jack server and try to become a client (only do once per stream).
+  jack_client_t *client = 0;
+  if ( mode == OUTPUT || ( mode == INPUT && stream_.mode != OUTPUT ) ) {
+    jack_options_t jackoptions = (jack_options_t) ( JackNoStartServer ); //JackNullOption;
+    jack_status_t *status = NULL;
+    if ( options && !options->streamName.empty() )
+      client = jack_client_open( options->streamName.c_str(), jackoptions, status );
+    else
+      client = jack_client_open( "RtApiJack", jackoptions, status );
+    if ( client == 0 ) {
+      errorText_ = "RtApiJack::probeDeviceOpen: Jack server not found or connection error!";
+      error( RtAudioError::WARNING );
+      return FAILURE;
+    }
+  }
+  else {
+    // The handle must have been created on an earlier pass.
+    client = handle->client;
+  }
+
+  const char **ports;
+  std::string port, previousPort, deviceName;
+  unsigned int nPorts = 0, nDevices = 0;
+  ports = jack_get_ports( client, NULL, NULL, 0 );
+  if ( ports ) {
+    // Parse the port names up to the first colon (:).
+    size_t iColon = 0;
+    do {
+      port = (char *) ports[ nPorts ];
+      iColon = port.find(":");
+      if ( iColon != std::string::npos ) {
+        port = port.substr( 0, iColon );
+        if ( port != previousPort ) {
+          if ( nDevices == device ) deviceName = port;
+          nDevices++;
+          previousPort = port;
+        }
+      }
+    } while ( ports[++nPorts] );
+    free( ports );
+  }
+
+  if ( device >= nDevices ) {
+    errorText_ = "RtApiJack::probeDeviceOpen: device ID is invalid!";
+    return FAILURE;
+  }
+
+  // Count the available ports containing the client name as device
+  // channels.  Jack "input ports" equal RtAudio output channels.
+  unsigned int nChannels = 0;
+  unsigned long flag = JackPortIsInput;
+  if ( mode == INPUT ) flag = JackPortIsOutput;
+  ports = jack_get_ports( client, deviceName.c_str(), NULL, flag );
+  if ( ports ) {
+    while ( ports[ nChannels ] ) nChannels++;
+    free( ports );
+  }
+
+  // Compare the jack ports for specified client to the requested number of channels.
+  if ( nChannels < (channels + firstChannel) ) {
+    errorStream_ << "RtApiJack::probeDeviceOpen: requested number of channels (" << channels << ") + offset (" << firstChannel << ") not found for specified device (" << device << ":" << deviceName << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Check the jack server sample rate.
+  unsigned int jackRate = jack_get_sample_rate( client );
+  if ( sampleRate != jackRate ) {
+    jack_client_close( client );
+    errorStream_ << "RtApiJack::probeDeviceOpen: the requested sample rate (" << sampleRate << ") is different than the JACK server rate (" << jackRate << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  stream_.sampleRate = jackRate;
+
+  // Get the latency of the JACK port.
+  ports = jack_get_ports( client, deviceName.c_str(), NULL, flag );
+  if ( ports[ firstChannel ] ) {
+    // Added by Ge Wang
+    jack_latency_callback_mode_t cbmode = (mode == INPUT ? JackCaptureLatency : JackPlaybackLatency);
+    // the range (usually the min and max are equal)
+    jack_latency_range_t latrange; latrange.min = latrange.max = 0;
+    // get the latency range
+    jack_port_get_latency_range( jack_port_by_name( client, ports[firstChannel] ), cbmode, &latrange );
+    // be optimistic, use the min!
+    stream_.latency[mode] = latrange.min;
+    //stream_.latency[mode] = jack_port_get_latency( jack_port_by_name( client, ports[ firstChannel ] ) );
+  }
+  free( ports );
+
+  // The jack server always uses 32-bit floating-point data.
+  stream_.deviceFormat[mode] = RTAUDIO_FLOAT32;
+  stream_.userFormat = format;
+
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) stream_.userInterleaved = false;
+  else stream_.userInterleaved = true;
+
+  // Jack always uses non-interleaved buffers.
+  stream_.deviceInterleaved[mode] = false;
+
+  // Jack always provides host byte-ordered data.
+  stream_.doByteSwap[mode] = false;
+
+  // Get the buffer size.  The buffer size and number of buffers
+  // (periods) is set when the jack server is started.
+  stream_.bufferSize = (int) jack_get_buffer_size( client );
+  *bufferSize = stream_.bufferSize;
+
+  stream_.nDeviceChannels[mode] = channels;
+  stream_.nUserChannels[mode] = channels;
+
+  // Set flags for buffer conversion.
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+       stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate our JackHandle structure for the stream.
+  if ( handle == 0 ) {
+    try {
+      handle = new JackHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiJack::probeDeviceOpen: error allocating JackHandle memory.";
+      goto error;
+    }
+
+    if ( pthread_cond_init(&handle->condition, NULL) ) {
+      errorText_ = "RtApiJack::probeDeviceOpen: error initializing pthread condition variable.";
+      goto error;
+    }
+    stream_.apiHandle = (void *) handle;
+    handle->client = client;
+  }
+  handle->deviceName[mode] = deviceName;
+
+  // Allocate necessary internal buffers.
+  unsigned long bufferBytes;
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiJack::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    if ( mode == OUTPUT )
+      bufferBytes = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+    else { // mode == INPUT
+      bufferBytes = stream_.nDeviceChannels[1] * formatBytes( stream_.deviceFormat[1] );
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes(stream_.deviceFormat[0]);
+        if ( bufferBytes < bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiJack::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  // Allocate memory for the Jack ports (channels) identifiers.
+  handle->ports[mode] = (jack_port_t **) malloc ( sizeof (jack_port_t *) * channels );
+  if ( handle->ports[mode] == NULL )  {
+    errorText_ = "RtApiJack::probeDeviceOpen: error allocating port memory.";
+    goto error;
+  }
+
+  stream_.device[mode] = device;
+  stream_.channelOffset[mode] = firstChannel;
+  stream_.state = STREAM_STOPPED;
+  stream_.callbackInfo.object = (void *) this;
+
+  if ( stream_.mode == OUTPUT && mode == INPUT )
+    // We had already set up the stream for output.
+    stream_.mode = DUPLEX;
+  else {
+    stream_.mode = mode;
+    jack_set_process_callback( handle->client, jackCallbackHandler, (void *) &stream_.callbackInfo );
+    jack_set_xrun_callback( handle->client, jackXrun, (void *) &handle );
+    jack_on_shutdown( handle->client, jackShutdown, (void *) &stream_.callbackInfo );
+  }
+
+  // Register our ports.
+  char label[64];
+  if ( mode == OUTPUT ) {
+    for ( unsigned int i=0; i<stream_.nUserChannels[0]; i++ ) {
+      snprintf( label, 64, "outport %d", i );
+      handle->ports[0][i] = jack_port_register( handle->client, (const char *)label,
+                                                JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0 );
+    }
+  }
+  else {
+    for ( unsigned int i=0; i<stream_.nUserChannels[1]; i++ ) {
+      snprintf( label, 64, "inport %d", i );
+      handle->ports[1][i] = jack_port_register( handle->client, (const char *)label,
+                                                JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0 );
+    }
+  }
+
+  // Setup the buffer conversion information structure.  We don't use
+  // buffers to do channel offsets, so we override that parameter
+  // here.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, 0 );
+
+  return SUCCESS;
+
+ error:
+  if ( handle ) {
+    pthread_cond_destroy( &handle->condition );
+    jack_client_close( handle->client );
+
+    if ( handle->ports[0] ) free( handle->ports[0] );
+    if ( handle->ports[1] ) free( handle->ports[1] );
+
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  return FAILURE;
+}
+
+void RtApiJack :: closeStream( void )
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiJack::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+  if ( handle ) {
+
+    if ( stream_.state == STREAM_RUNNING )
+      jack_deactivate( handle->client );
+
+    jack_client_close( handle->client );
+  }
+
+  if ( handle ) {
+    if ( handle->ports[0] ) free( handle->ports[0] );
+    if ( handle->ports[1] ) free( handle->ports[1] );
+    pthread_cond_destroy( &handle->condition );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+void RtApiJack :: startStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiJack::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+  int result = jack_activate( handle->client );
+  if ( result ) {
+    errorText_ = "RtApiJack::startStream(): unable to activate JACK client!";
+    goto unlock;
+  }
+
+  const char **ports;
+
+  // Get the list of available ports.
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    result = 1;
+    ports = jack_get_ports( handle->client, handle->deviceName[0].c_str(), NULL, JackPortIsInput);
+    if ( ports == NULL) {
+      errorText_ = "RtApiJack::startStream(): error determining available JACK input ports!";
+      goto unlock;
+    }
+
+    // Now make the port connections.  Since RtAudio wasn't designed to
+    // allow the user to select particular channels of a device, we'll
+    // just open the first "nChannels" ports with offset.
+    for ( unsigned int i=0; i<stream_.nUserChannels[0]; i++ ) {
+      result = 1;
+      if ( ports[ stream_.channelOffset[0] + i ] )
+        result = jack_connect( handle->client, jack_port_name( handle->ports[0][i] ), ports[ stream_.channelOffset[0] + i ] );
+      if ( result ) {
+        free( ports );
+        errorText_ = "RtApiJack::startStream(): error connecting output ports!";
+        goto unlock;
+      }
+    }
+    free(ports);
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+    result = 1;
+    ports = jack_get_ports( handle->client, handle->deviceName[1].c_str(), NULL, JackPortIsOutput );
+    if ( ports == NULL) {
+      errorText_ = "RtApiJack::startStream(): error determining available JACK output ports!";
+      goto unlock;
+    }
+
+    // Now make the port connections.  See note above.
+    for ( unsigned int i=0; i<stream_.nUserChannels[1]; i++ ) {
+      result = 1;
+      if ( ports[ stream_.channelOffset[1] + i ] )
+        result = jack_connect( handle->client, ports[ stream_.channelOffset[1] + i ], jack_port_name( handle->ports[1][i] ) );
+      if ( result ) {
+        free( ports );
+        errorText_ = "RtApiJack::startStream(): error connecting input ports!";
+        goto unlock;
+      }
+    }
+    free(ports);
+  }
+
+  handle->drainCounter = 0;
+  handle->internalDrain = false;
+  stream_.state = STREAM_RUNNING;
+
+ unlock:
+  if ( result == 0 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiJack :: stopStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiJack::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    if ( handle->drainCounter == 0 ) {
+      handle->drainCounter = 2;
+      pthread_cond_wait( &handle->condition, &stream_.mutex ); // block until signaled
+    }
+  }
+
+  jack_deactivate( handle->client );
+  stream_.state = STREAM_STOPPED;
+}
+
+void RtApiJack :: abortStream( void )
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiJack::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+  handle->drainCounter = 2;
+
+  stopStream();
+}
+
+// This function will be called by a spawned thread when the user
+// callback function signals that the stream should be stopped or
+// aborted.  It is necessary to handle it this way because the
+// callbackEvent() function must return before the jack_deactivate()
+// function will return.
+static void *jackStopStream( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiJack *object = (RtApiJack *) info->object;
+
+  object->stopStream();
+  pthread_exit( NULL );
+}
+
+bool RtApiJack :: callbackEvent( unsigned long nframes )
+{
+  if ( stream_.state == STREAM_STOPPED || stream_.state == STREAM_STOPPING ) return SUCCESS;
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiCore::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return FAILURE;
+  }
+  if ( stream_.bufferSize != nframes ) {
+    errorText_ = "RtApiCore::callbackEvent(): the JACK buffer size has changed ... cannot process!";
+    error( RtAudioError::WARNING );
+    return FAILURE;
+  }
+
+  CallbackInfo *info = (CallbackInfo *) &stream_.callbackInfo;
+  JackHandle *handle = (JackHandle *) stream_.apiHandle;
+
+  // Check if we were draining the stream and signal is finished.
+  if ( handle->drainCounter > 3 ) {
+    ThreadHandle threadId;
+
+    stream_.state = STREAM_STOPPING;
+    if ( handle->internalDrain == true )
+      pthread_create( &threadId, NULL, jackStopStream, info );
+    else
+      pthread_cond_signal( &handle->condition );
+    return SUCCESS;
+  }
+
+  // Invoke user callback first, to get fresh output data.
+  if ( handle->drainCounter == 0 ) {
+    RtAudioCallback callback = (RtAudioCallback) info->callback;
+    double streamTime = getStreamTime();
+    RtAudioStreamStatus status = 0;
+    if ( stream_.mode != INPUT && handle->xrun[0] == true ) {
+      status |= RTAUDIO_OUTPUT_UNDERFLOW;
+      handle->xrun[0] = false;
+    }
+    if ( stream_.mode != OUTPUT && handle->xrun[1] == true ) {
+      status |= RTAUDIO_INPUT_OVERFLOW;
+      handle->xrun[1] = false;
+    }
+    int cbReturnValue = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                                  stream_.bufferSize, streamTime, status, info->userData );
+    if ( cbReturnValue == 2 ) {
+      stream_.state = STREAM_STOPPING;
+      handle->drainCounter = 2;
+      ThreadHandle id;
+      pthread_create( &id, NULL, jackStopStream, info );
+      return SUCCESS;
+    }
+    else if ( cbReturnValue == 1 ) {
+      handle->drainCounter = 1;
+      handle->internalDrain = true;
+    }
+  }
+
+  jack_default_audio_sample_t *jackbuffer;
+  unsigned long bufferBytes = nframes * sizeof( jack_default_audio_sample_t );
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    if ( handle->drainCounter > 1 ) { // write zeros to the output stream
+
+      for ( unsigned int i=0; i<stream_.nDeviceChannels[0]; i++ ) {
+        jackbuffer = (jack_default_audio_sample_t *) jack_port_get_buffer( handle->ports[0][i], (jack_nframes_t) nframes );
+        memset( jackbuffer, 0, bufferBytes );
+      }
+
+    }
+    else if ( stream_.doConvertBuffer[0] ) {
+
+      convertBuffer( stream_.deviceBuffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+
+      for ( unsigned int i=0; i<stream_.nDeviceChannels[0]; i++ ) {
+        jackbuffer = (jack_default_audio_sample_t *) jack_port_get_buffer( handle->ports[0][i], (jack_nframes_t) nframes );
+        memcpy( jackbuffer, &stream_.deviceBuffer[i*bufferBytes], bufferBytes );
+      }
+    }
+    else { // no buffer conversion
+      for ( unsigned int i=0; i<stream_.nUserChannels[0]; i++ ) {
+        jackbuffer = (jack_default_audio_sample_t *) jack_port_get_buffer( handle->ports[0][i], (jack_nframes_t) nframes );
+        memcpy( jackbuffer, &stream_.userBuffer[0][i*bufferBytes], bufferBytes );
+      }
+    }
+  }
+
+  // Don't bother draining input
+  if ( handle->drainCounter ) {
+    handle->drainCounter++;
+    goto unlock;
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    if ( stream_.doConvertBuffer[1] ) {
+      for ( unsigned int i=0; i<stream_.nDeviceChannels[1]; i++ ) {
+        jackbuffer = (jack_default_audio_sample_t *) jack_port_get_buffer( handle->ports[1][i], (jack_nframes_t) nframes );
+        memcpy( &stream_.deviceBuffer[i*bufferBytes], jackbuffer, bufferBytes );
+      }
+      convertBuffer( stream_.userBuffer[1], stream_.deviceBuffer, stream_.convertInfo[1] );
+    }
+    else { // no buffer conversion
+      for ( unsigned int i=0; i<stream_.nUserChannels[1]; i++ ) {
+        jackbuffer = (jack_default_audio_sample_t *) jack_port_get_buffer( handle->ports[1][i], (jack_nframes_t) nframes );
+        memcpy( &stream_.userBuffer[1][i*bufferBytes], jackbuffer, bufferBytes );
+      }
+    }
+  }
+
+ unlock:
+  RtApi::tickStreamTime();
+  return SUCCESS;
+}
+  //******************** End of __UNIX_JACK__ *********************//
+#endif
+
+#if defined(__WINDOWS_ASIO__) // ASIO API on Windows
+
+// The ASIO API is designed around a callback scheme, so this
+// implementation is similar to that used for OS-X CoreAudio and Linux
+// Jack.  The primary constraint with ASIO is that it only allows
+// access to a single driver at a time.  Thus, it is not possible to
+// have more than one simultaneous RtAudio stream.
+//
+// This implementation also requires a number of external ASIO files
+// and a few global variables.  The ASIO callback scheme does not
+// allow for the passing of user data, so we must create a global
+// pointer to our callbackInfo structure.
+//
+// On unix systems, we make use of a pthread condition variable.
+// Since there is no equivalent in Windows, I hacked something based
+// on information found in
+// http://www.cs.wustl.edu/~schmidt/win32-cv-1.html.
+
+#include "asiosys.h"
+#include "asio.h"
+#include "iasiothiscallresolver.h"
+#include "asiodrivers.h"
+#include <cmath>
+
+static AsioDrivers drivers;
+static ASIOCallbacks asioCallbacks;
+static ASIODriverInfo driverInfo;
+static CallbackInfo *asioCallbackInfo;
+static bool asioXRun;
+
+struct AsioHandle {
+  int drainCounter;       // Tracks callback counts when draining
+  bool internalDrain;     // Indicates if stop is initiated from callback or not.
+  ASIOBufferInfo *bufferInfos;
+  HANDLE condition;
+
+  AsioHandle()
+    :drainCounter(0), internalDrain(false), bufferInfos(0) {}
+};
+
+// Function declarations (definitions at end of section)
+static const char* getAsioErrorString( ASIOError result );
+static void sampleRateChanged( ASIOSampleRate sRate );
+static long asioMessages( long selector, long value, void* message, double* opt );
+
+RtApiAsio :: RtApiAsio()
+{
+  // ASIO cannot run on a multi-threaded appartment. You can call
+  // CoInitialize beforehand, but it must be for appartment threading
+  // (in which case, CoInitilialize will return S_FALSE here).
+  coInitialized_ = false;
+  HRESULT hr = CoInitialize( NULL ); 
+  if ( FAILED(hr) ) {
+    errorText_ = "RtApiAsio::ASIO requires a single-threaded appartment. Call CoInitializeEx(0,COINIT_APARTMENTTHREADED)";
+    error( RtAudioError::WARNING );
+  }
+  coInitialized_ = true;
+
+  drivers.removeCurrentDriver();
+  driverInfo.asioVersion = 2;
+
+  // See note in DirectSound implementation about GetDesktopWindow().
+  driverInfo.sysRef = GetForegroundWindow();
+}
+
+RtApiAsio :: ~RtApiAsio()
+{
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+  if ( coInitialized_ ) CoUninitialize();
+}
+
+unsigned int RtApiAsio :: getDeviceCount( void )
+{
+  return (unsigned int) drivers.asioGetNumDev();
+}
+
+RtAudio::DeviceInfo RtApiAsio :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  // Get device ID
+  unsigned int nDevices = getDeviceCount();
+  if ( nDevices == 0 ) {
+    errorText_ = "RtApiAsio::getDeviceInfo: no devices found!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  if ( device >= nDevices ) {
+    errorText_ = "RtApiAsio::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  // If a stream is already open, we cannot probe other devices.  Thus, use the saved results.
+  if ( stream_.state != STREAM_CLOSED ) {
+    if ( device >= devices_.size() ) {
+      errorText_ = "RtApiAsio::getDeviceInfo: device ID was not present before stream was opened.";
+      error( RtAudioError::WARNING );
+      return info;
+    }
+    return devices_[ device ];
+  }
+
+  char driverName[32];
+  ASIOError result = drivers.asioGetDriverName( (int) device, driverName, 32 );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::getDeviceInfo: unable to get driver name (" << getAsioErrorString( result ) << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  info.name = driverName;
+
+  if ( !drivers.loadDriver( driverName ) ) {
+    errorStream_ << "RtApiAsio::getDeviceInfo: unable to load driver (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  result = ASIOInit( &driverInfo );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::getDeviceInfo: error (" << getAsioErrorString( result ) << ") initializing driver (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Determine the device channel information.
+  long inputChannels, outputChannels;
+  result = ASIOGetChannels( &inputChannels, &outputChannels );
+  if ( result != ASE_OK ) {
+    drivers.removeCurrentDriver();
+    errorStream_ << "RtApiAsio::getDeviceInfo: error (" << getAsioErrorString( result ) << ") getting channel count (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  info.outputChannels = outputChannels;
+  info.inputChannels = inputChannels;
+  if ( info.outputChannels > 0 && info.inputChannels > 0 )
+    info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+
+  // Determine the supported sample rates.
+  info.sampleRates.clear();
+  for ( unsigned int i=0; i<MAX_SAMPLE_RATES; i++ ) {
+    result = ASIOCanSampleRate( (ASIOSampleRate) SAMPLE_RATES[i] );
+    if ( result == ASE_OK ) {
+      info.sampleRates.push_back( SAMPLE_RATES[i] );
+
+      if ( !info.preferredSampleRate || ( SAMPLE_RATES[i] <= 48000 && SAMPLE_RATES[i] > info.preferredSampleRate ) )
+        info.preferredSampleRate = SAMPLE_RATES[i];
+    }
+  }
+
+  // Determine supported data types ... just check first channel and assume rest are the same.
+  ASIOChannelInfo channelInfo;
+  channelInfo.channel = 0;
+  channelInfo.isInput = true;
+  if ( info.inputChannels <= 0 ) channelInfo.isInput = false;
+  result = ASIOGetChannelInfo( &channelInfo );
+  if ( result != ASE_OK ) {
+    drivers.removeCurrentDriver();
+    errorStream_ << "RtApiAsio::getDeviceInfo: error (" << getAsioErrorString( result ) << ") getting driver channel info (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  info.nativeFormats = 0;
+  if ( channelInfo.type == ASIOSTInt16MSB || channelInfo.type == ASIOSTInt16LSB )
+    info.nativeFormats |= RTAUDIO_SINT16;
+  else if ( channelInfo.type == ASIOSTInt32MSB || channelInfo.type == ASIOSTInt32LSB )
+    info.nativeFormats |= RTAUDIO_SINT32;
+  else if ( channelInfo.type == ASIOSTFloat32MSB || channelInfo.type == ASIOSTFloat32LSB )
+    info.nativeFormats |= RTAUDIO_FLOAT32;
+  else if ( channelInfo.type == ASIOSTFloat64MSB || channelInfo.type == ASIOSTFloat64LSB )
+    info.nativeFormats |= RTAUDIO_FLOAT64;
+  else if ( channelInfo.type == ASIOSTInt24MSB || channelInfo.type == ASIOSTInt24LSB )
+    info.nativeFormats |= RTAUDIO_SINT24;
+
+  if ( info.outputChannels > 0 )
+    if ( getDefaultOutputDevice() == device ) info.isDefaultOutput = true;
+  if ( info.inputChannels > 0 )
+    if ( getDefaultInputDevice() == device ) info.isDefaultInput = true;
+
+  info.probed = true;
+  drivers.removeCurrentDriver();
+  return info;
+}
+
+static void bufferSwitch( long index, ASIOBool /*processNow*/ )
+{
+  RtApiAsio *object = (RtApiAsio *) asioCallbackInfo->object;
+  object->callbackEvent( index );
+}
+
+void RtApiAsio :: saveDeviceInfo( void )
+{
+  devices_.clear();
+
+  unsigned int nDevices = getDeviceCount();
+  devices_.resize( nDevices );
+  for ( unsigned int i=0; i<nDevices; i++ )
+    devices_[i] = getDeviceInfo( i );
+}
+
+bool RtApiAsio :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                   unsigned int firstChannel, unsigned int sampleRate,
+                                   RtAudioFormat format, unsigned int *bufferSize,
+                                   RtAudio::StreamOptions *options )
+{////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+  bool isDuplexInput =  mode == INPUT && stream_.mode == OUTPUT;
+
+  // For ASIO, a duplex stream MUST use the same driver.
+  if ( isDuplexInput && stream_.device[0] != device ) {
+    errorText_ = "RtApiAsio::probeDeviceOpen: an ASIO duplex stream must use the same device for input and output!";
+    return FAILURE;
+  }
+
+  char driverName[32];
+  ASIOError result = drivers.asioGetDriverName( (int) device, driverName, 32 );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: unable to get driver name (" << getAsioErrorString( result ) << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Only load the driver once for duplex stream.
+  if ( !isDuplexInput ) {
+    // The getDeviceInfo() function will not work when a stream is open
+    // because ASIO does not allow multiple devices to run at the same
+    // time.  Thus, we'll probe the system before opening a stream and
+    // save the results for use by getDeviceInfo().
+    this->saveDeviceInfo();
+
+    if ( !drivers.loadDriver( driverName ) ) {
+      errorStream_ << "RtApiAsio::probeDeviceOpen: unable to load driver (" << driverName << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    result = ASIOInit( &driverInfo );
+    if ( result != ASE_OK ) {
+      errorStream_ << "RtApiAsio::probeDeviceOpen: error (" << getAsioErrorString( result ) << ") initializing driver (" << driverName << ").";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+
+  // keep them before any "goto error", they are used for error cleanup + goto device boundary checks
+  bool buffersAllocated = false;
+  AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+  unsigned int nChannels;
+
+
+  // Check the device channel count.
+  long inputChannels, outputChannels;
+  result = ASIOGetChannels( &inputChannels, &outputChannels );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: error (" << getAsioErrorString( result ) << ") getting channel count (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  if ( ( mode == OUTPUT && (channels+firstChannel) > (unsigned int) outputChannels) ||
+       ( mode == INPUT && (channels+firstChannel) > (unsigned int) inputChannels) ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") does not support requested channel count (" << channels << ") + offset (" << firstChannel << ").";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+  stream_.nDeviceChannels[mode] = channels;
+  stream_.nUserChannels[mode] = channels;
+  stream_.channelOffset[mode] = firstChannel;
+
+  // Verify the sample rate is supported.
+  result = ASIOCanSampleRate( (ASIOSampleRate) sampleRate );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") does not support requested sample rate (" << sampleRate << ").";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  // Get the current sample rate
+  ASIOSampleRate currentRate;
+  result = ASIOGetSampleRate( &currentRate );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error getting sample rate.";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  // Set the sample rate only if necessary
+  if ( currentRate != sampleRate ) {
+    result = ASIOSetSampleRate( (ASIOSampleRate) sampleRate );
+    if ( result != ASE_OK ) {
+      errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error setting sample rate (" << sampleRate << ").";
+      errorText_ = errorStream_.str();
+      goto error;
+    }
+  }
+
+  // Determine the driver data type.
+  ASIOChannelInfo channelInfo;
+  channelInfo.channel = 0;
+  if ( mode == OUTPUT ) channelInfo.isInput = false;
+  else channelInfo.isInput = true;
+  result = ASIOGetChannelInfo( &channelInfo );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error (" << getAsioErrorString( result ) << ") getting data format.";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  // Assuming WINDOWS host is always little-endian.
+  stream_.doByteSwap[mode] = false;
+  stream_.userFormat = format;
+  stream_.deviceFormat[mode] = 0;
+  if ( channelInfo.type == ASIOSTInt16MSB || channelInfo.type == ASIOSTInt16LSB ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+    if ( channelInfo.type == ASIOSTInt16MSB ) stream_.doByteSwap[mode] = true;
+  }
+  else if ( channelInfo.type == ASIOSTInt32MSB || channelInfo.type == ASIOSTInt32LSB ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+    if ( channelInfo.type == ASIOSTInt32MSB ) stream_.doByteSwap[mode] = true;
+  }
+  else if ( channelInfo.type == ASIOSTFloat32MSB || channelInfo.type == ASIOSTFloat32LSB ) {
+    stream_.deviceFormat[mode] = RTAUDIO_FLOAT32;
+    if ( channelInfo.type == ASIOSTFloat32MSB ) stream_.doByteSwap[mode] = true;
+  }
+  else if ( channelInfo.type == ASIOSTFloat64MSB || channelInfo.type == ASIOSTFloat64LSB ) {
+    stream_.deviceFormat[mode] = RTAUDIO_FLOAT64;
+    if ( channelInfo.type == ASIOSTFloat64MSB ) stream_.doByteSwap[mode] = true;
+  }
+  else if ( channelInfo.type == ASIOSTInt24MSB || channelInfo.type == ASIOSTInt24LSB ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+    if ( channelInfo.type == ASIOSTInt24MSB ) stream_.doByteSwap[mode] = true;
+  }
+
+  if ( stream_.deviceFormat[mode] == 0 ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") data format not supported by RtAudio.";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  // Set the buffer size.  For a duplex stream, this will end up
+  // setting the buffer size based on the input constraints, which
+  // should be ok.
+  long minSize, maxSize, preferSize, granularity;
+  result = ASIOGetBufferSize( &minSize, &maxSize, &preferSize, &granularity );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error (" << getAsioErrorString( result ) << ") getting buffer size.";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  if ( isDuplexInput ) {
+    // When this is the duplex input (output was opened before), then we have to use the same
+    // buffersize as the output, because it might use the preferred buffer size, which most
+    // likely wasn't passed as input to this. The buffer sizes have to be identically anyway,
+    // So instead of throwing an error, make them equal. The caller uses the reference
+    // to the "bufferSize" param as usual to set up processing buffers.
+
+    *bufferSize = stream_.bufferSize;
+
+  } else {
+    if ( *bufferSize == 0 ) *bufferSize = preferSize;
+    else if ( *bufferSize < (unsigned int) minSize ) *bufferSize = (unsigned int) minSize;
+    else if ( *bufferSize > (unsigned int) maxSize ) *bufferSize = (unsigned int) maxSize;
+    else if ( granularity == -1 ) {
+      // Make sure bufferSize is a power of two.
+      int log2_of_min_size = 0;
+      int log2_of_max_size = 0;
+
+      for ( unsigned int i = 0; i < sizeof(long) * 8; i++ ) {
+        if ( minSize & ((long)1 << i) ) log2_of_min_size = i;
+        if ( maxSize & ((long)1 << i) ) log2_of_max_size = i;
+      }
+
+      long min_delta = std::abs( (long)*bufferSize - ((long)1 << log2_of_min_size) );
+      int min_delta_num = log2_of_min_size;
+
+      for (int i = log2_of_min_size + 1; i <= log2_of_max_size; i++) {
+        long current_delta = std::abs( (long)*bufferSize - ((long)1 << i) );
+        if (current_delta < min_delta) {
+          min_delta = current_delta;
+          min_delta_num = i;
+        }
+      }
+
+      *bufferSize = ( (unsigned int)1 << min_delta_num );
+      if ( *bufferSize < (unsigned int) minSize ) *bufferSize = (unsigned int) minSize;
+      else if ( *bufferSize > (unsigned int) maxSize ) *bufferSize = (unsigned int) maxSize;
+    }
+    else if ( granularity != 0 ) {
+      // Set to an even multiple of granularity, rounding up.
+      *bufferSize = (*bufferSize + granularity-1) / granularity * granularity;
+    }
+  }
+
+  /*
+  // we don't use it anymore, see above!
+  // Just left it here for the case...
+  if ( isDuplexInput && stream_.bufferSize != *bufferSize ) {
+    errorText_ = "RtApiAsio::probeDeviceOpen: input/output buffersize discrepancy!";
+    goto error;
+  }
+  */
+
+  stream_.bufferSize = *bufferSize;
+  stream_.nBuffers = 2;
+
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) stream_.userInterleaved = false;
+  else stream_.userInterleaved = true;
+
+  // ASIO always uses non-interleaved buffers.
+  stream_.deviceInterleaved[mode] = false;
+
+  // Allocate, if necessary, our AsioHandle structure for the stream.
+  if ( handle == 0 ) {
+    try {
+      handle = new AsioHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiAsio::probeDeviceOpen: error allocating AsioHandle memory.";
+      goto error;
+    }
+    handle->bufferInfos = 0;
+
+    // Create a manual-reset event.
+    handle->condition = CreateEvent( NULL,   // no security
+                                     TRUE,   // manual-reset
+                                     FALSE,  // non-signaled initially
+                                     NULL ); // unnamed
+    stream_.apiHandle = (void *) handle;
+  }
+
+  // Create the ASIO internal buffers.  Since RtAudio sets up input
+  // and output separately, we'll have to dispose of previously
+  // created output buffers for a duplex stream.
+  if ( mode == INPUT && stream_.mode == OUTPUT ) {
+    ASIODisposeBuffers();
+    if ( handle->bufferInfos ) free( handle->bufferInfos );
+  }
+
+  // Allocate, initialize, and save the bufferInfos in our stream callbackInfo structure.
+  unsigned int i;
+  nChannels = stream_.nDeviceChannels[0] + stream_.nDeviceChannels[1];
+  handle->bufferInfos = (ASIOBufferInfo *) malloc( nChannels * sizeof(ASIOBufferInfo) );
+  if ( handle->bufferInfos == NULL ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: error allocating bufferInfo memory for driver (" << driverName << ").";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+
+  ASIOBufferInfo *infos;
+  infos = handle->bufferInfos;
+  for ( i=0; i<stream_.nDeviceChannels[0]; i++, infos++ ) {
+    infos->isInput = ASIOFalse;
+    infos->channelNum = i + stream_.channelOffset[0];
+    infos->buffers[0] = infos->buffers[1] = 0;
+  }
+  for ( i=0; i<stream_.nDeviceChannels[1]; i++, infos++ ) {
+    infos->isInput = ASIOTrue;
+    infos->channelNum = i + stream_.channelOffset[1];
+    infos->buffers[0] = infos->buffers[1] = 0;
+  }
+
+  // prepare for callbacks
+  stream_.sampleRate = sampleRate;
+  stream_.device[mode] = device;
+  stream_.mode = isDuplexInput ? DUPLEX : mode;
+
+  // store this class instance before registering callbacks, that are going to use it
+  asioCallbackInfo = &stream_.callbackInfo;
+  stream_.callbackInfo.object = (void *) this;
+
+  // Set up the ASIO callback structure and create the ASIO data buffers.
+  asioCallbacks.bufferSwitch = &bufferSwitch;
+  asioCallbacks.sampleRateDidChange = &sampleRateChanged;
+  asioCallbacks.asioMessage = &asioMessages;
+  asioCallbacks.bufferSwitchTimeInfo = NULL;
+  result = ASIOCreateBuffers( handle->bufferInfos, nChannels, stream_.bufferSize, &asioCallbacks );
+  if ( result != ASE_OK ) {
+    // Standard method failed. This can happen with strict/misbehaving drivers that return valid buffer size ranges
+    // but only accept the preferred buffer size as parameter for ASIOCreateBuffers. eg. Creatives ASIO driver
+    // in that case, let's be naïve and try that instead
+    *bufferSize = preferSize;
+    stream_.bufferSize = *bufferSize;
+    result = ASIOCreateBuffers( handle->bufferInfos, nChannels, stream_.bufferSize, &asioCallbacks );
+  }
+
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error (" << getAsioErrorString( result ) << ") creating buffers.";
+    errorText_ = errorStream_.str();
+    goto error;
+  }
+  buffersAllocated = true;  
+  stream_.state = STREAM_STOPPED;
+
+  // Set flags for buffer conversion.
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+       stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate necessary internal buffers
+  unsigned long bufferBytes;
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiAsio::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( isDuplexInput && stream_.deviceBuffer ) {
+      unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+      if ( bufferBytes <= bytesOut ) makeBuffer = false;
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiAsio::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  // Determine device latencies
+  long inputLatency, outputLatency;
+  result = ASIOGetLatencies( &inputLatency, &outputLatency );
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::probeDeviceOpen: driver (" << driverName << ") error (" << getAsioErrorString( result ) << ") getting latency.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING); // warn but don't fail
+  }
+  else {
+    stream_.latency[0] = outputLatency;
+    stream_.latency[1] = inputLatency;
+  }
+
+  // Setup the buffer conversion information structure.  We don't use
+  // buffers to do channel offsets, so we override that parameter
+  // here.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, 0 );
+
+  return SUCCESS;
+
+ error:
+  if ( !isDuplexInput ) {
+    // the cleanup for error in the duplex input, is done by RtApi::openStream
+    // So we clean up for single channel only
+
+    if ( buffersAllocated )
+      ASIODisposeBuffers();
+
+    drivers.removeCurrentDriver();
+
+    if ( handle ) {
+      CloseHandle( handle->condition );
+      if ( handle->bufferInfos )
+        free( handle->bufferInfos );
+
+      delete handle;
+      stream_.apiHandle = 0;
+    }
+
+
+    if ( stream_.userBuffer[mode] ) {
+      free( stream_.userBuffer[mode] );
+      stream_.userBuffer[mode] = 0;
+    }
+
+    if ( stream_.deviceBuffer ) {
+      free( stream_.deviceBuffer );
+      stream_.deviceBuffer = 0;
+    }
+  }
+
+  return FAILURE;
+}////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+void RtApiAsio :: closeStream()
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiAsio::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  if ( stream_.state == STREAM_RUNNING ) {
+    stream_.state = STREAM_STOPPED;
+    ASIOStop();
+  }
+  ASIODisposeBuffers();
+  drivers.removeCurrentDriver();
+
+  AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+  if ( handle ) {
+    CloseHandle( handle->condition );
+    if ( handle->bufferInfos )
+      free( handle->bufferInfos );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+bool stopThreadCalled = false;
+
+void RtApiAsio :: startStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiAsio::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+  ASIOError result = ASIOStart();
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::startStream: error (" << getAsioErrorString( result ) << ") starting device.";
+    errorText_ = errorStream_.str();
+    goto unlock;
+  }
+
+  handle->drainCounter = 0;
+  handle->internalDrain = false;
+  ResetEvent( handle->condition );
+  stream_.state = STREAM_RUNNING;
+  asioXRun = false;
+
+ unlock:
+  stopThreadCalled = false;
+
+  if ( result == ASE_OK ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiAsio :: stopStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiAsio::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    if ( handle->drainCounter == 0 ) {
+      handle->drainCounter = 2;
+      WaitForSingleObject( handle->condition, INFINITE );  // block until signaled
+    }
+  }
+
+  stream_.state = STREAM_STOPPED;
+
+  ASIOError result = ASIOStop();
+  if ( result != ASE_OK ) {
+    errorStream_ << "RtApiAsio::stopStream: error (" << getAsioErrorString( result ) << ") stopping device.";
+    errorText_ = errorStream_.str();
+  }
+
+  if ( result == ASE_OK ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiAsio :: abortStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiAsio::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // The following lines were commented-out because some behavior was
+  // noted where the device buffers need to be zeroed to avoid
+  // continuing sound, even when the device buffers are completely
+  // disposed.  So now, calling abort is the same as calling stop.
+  // AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+  // handle->drainCounter = 2;
+  stopStream();
+}
+
+// This function will be called by a spawned thread when the user
+// callback function signals that the stream should be stopped or
+// aborted.  It is necessary to handle it this way because the
+// callbackEvent() function must return before the ASIOStop()
+// function will return.
+static unsigned __stdcall asioStopStream( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiAsio *object = (RtApiAsio *) info->object;
+
+  object->stopStream();
+  _endthreadex( 0 );
+  return 0;
+}
+
+bool RtApiAsio :: callbackEvent( long bufferIndex )
+{
+  if ( stream_.state == STREAM_STOPPED || stream_.state == STREAM_STOPPING ) return SUCCESS;
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiAsio::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return FAILURE;
+  }
+
+  CallbackInfo *info = (CallbackInfo *) &stream_.callbackInfo;
+  AsioHandle *handle = (AsioHandle *) stream_.apiHandle;
+
+  // Check if we were draining the stream and signal if finished.
+  if ( handle->drainCounter > 3 ) {
+
+    stream_.state = STREAM_STOPPING;
+    if ( handle->internalDrain == false )
+      SetEvent( handle->condition );
+    else { // spawn a thread to stop the stream
+      unsigned threadId;
+      stream_.callbackInfo.thread = _beginthreadex( NULL, 0, &asioStopStream,
+                                                    &stream_.callbackInfo, 0, &threadId );
+    }
+    return SUCCESS;
+  }
+
+  // Invoke user callback to get fresh output data UNLESS we are
+  // draining stream.
+  if ( handle->drainCounter == 0 ) {
+    RtAudioCallback callback = (RtAudioCallback) info->callback;
+    double streamTime = getStreamTime();
+    RtAudioStreamStatus status = 0;
+    if ( stream_.mode != INPUT && asioXRun == true ) {
+      status |= RTAUDIO_OUTPUT_UNDERFLOW;
+      asioXRun = false;
+    }
+    if ( stream_.mode != OUTPUT && asioXRun == true ) {
+      status |= RTAUDIO_INPUT_OVERFLOW;
+      asioXRun = false;
+    }
+    int cbReturnValue = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                                     stream_.bufferSize, streamTime, status, info->userData );
+    if ( cbReturnValue == 2 ) {
+      stream_.state = STREAM_STOPPING;
+      handle->drainCounter = 2;
+      unsigned threadId;
+      stream_.callbackInfo.thread = _beginthreadex( NULL, 0, &asioStopStream,
+                                                    &stream_.callbackInfo, 0, &threadId );
+      return SUCCESS;
+    }
+    else if ( cbReturnValue == 1 ) {
+      handle->drainCounter = 1;
+      handle->internalDrain = true;
+    }
+  }
+
+  unsigned int nChannels, bufferBytes, i, j;
+  nChannels = stream_.nDeviceChannels[0] + stream_.nDeviceChannels[1];
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    bufferBytes = stream_.bufferSize * formatBytes( stream_.deviceFormat[0] );
+
+    if ( handle->drainCounter > 1 ) { // write zeros to the output stream
+
+      for ( i=0, j=0; i<nChannels; i++ ) {
+        if ( handle->bufferInfos[i].isInput != ASIOTrue )
+          memset( handle->bufferInfos[i].buffers[bufferIndex], 0, bufferBytes );
+      }
+
+    }
+    else if ( stream_.doConvertBuffer[0] ) {
+
+      convertBuffer( stream_.deviceBuffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+      if ( stream_.doByteSwap[0] )
+        byteSwapBuffer( stream_.deviceBuffer,
+                        stream_.bufferSize * stream_.nDeviceChannels[0],
+                        stream_.deviceFormat[0] );
+
+      for ( i=0, j=0; i<nChannels; i++ ) {
+        if ( handle->bufferInfos[i].isInput != ASIOTrue )
+          memcpy( handle->bufferInfos[i].buffers[bufferIndex],
+                  &stream_.deviceBuffer[j++*bufferBytes], bufferBytes );
+      }
+
+    }
+    else {
+
+      if ( stream_.doByteSwap[0] )
+        byteSwapBuffer( stream_.userBuffer[0],
+                        stream_.bufferSize * stream_.nUserChannels[0],
+                        stream_.userFormat );
+
+      for ( i=0, j=0; i<nChannels; i++ ) {
+        if ( handle->bufferInfos[i].isInput != ASIOTrue )
+          memcpy( handle->bufferInfos[i].buffers[bufferIndex],
+                  &stream_.userBuffer[0][bufferBytes*j++], bufferBytes );
+      }
+
+    }
+  }
+
+  // Don't bother draining input
+  if ( handle->drainCounter ) {
+    handle->drainCounter++;
+    goto unlock;
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    bufferBytes = stream_.bufferSize * formatBytes(stream_.deviceFormat[1]);
+
+    if (stream_.doConvertBuffer[1]) {
+
+      // Always interleave ASIO input data.
+      for ( i=0, j=0; i<nChannels; i++ ) {
+        if ( handle->bufferInfos[i].isInput == ASIOTrue )
+          memcpy( &stream_.deviceBuffer[j++*bufferBytes],
+                  handle->bufferInfos[i].buffers[bufferIndex],
+                  bufferBytes );
+      }
+
+      if ( stream_.doByteSwap[1] )
+        byteSwapBuffer( stream_.deviceBuffer,
+                        stream_.bufferSize * stream_.nDeviceChannels[1],
+                        stream_.deviceFormat[1] );
+      convertBuffer( stream_.userBuffer[1], stream_.deviceBuffer, stream_.convertInfo[1] );
+
+    }
+    else {
+      for ( i=0, j=0; i<nChannels; i++ ) {
+        if ( handle->bufferInfos[i].isInput == ASIOTrue ) {
+          memcpy( &stream_.userBuffer[1][bufferBytes*j++],
+                  handle->bufferInfos[i].buffers[bufferIndex],
+                  bufferBytes );
+        }
+      }
+
+      if ( stream_.doByteSwap[1] )
+        byteSwapBuffer( stream_.userBuffer[1],
+                        stream_.bufferSize * stream_.nUserChannels[1],
+                        stream_.userFormat );
+    }
+  }
+
+ unlock:
+  // The following call was suggested by Malte Clasen.  While the API
+  // documentation indicates it should not be required, some device
+  // drivers apparently do not function correctly without it.
+  ASIOOutputReady();
+
+  RtApi::tickStreamTime();
+  return SUCCESS;
+}
+
+static void sampleRateChanged( ASIOSampleRate sRate )
+{
+  // The ASIO documentation says that this usually only happens during
+  // external sync.  Audio processing is not stopped by the driver,
+  // actual sample rate might not have even changed, maybe only the
+  // sample rate status of an AES/EBU or S/PDIF digital input at the
+  // audio device.
+
+  RtApi *object = (RtApi *) asioCallbackInfo->object;
+  try {
+    object->stopStream();
+  }
+  catch ( RtAudioError &exception ) {
+    std::cerr << "\nRtApiAsio: sampleRateChanged() error (" << exception.getMessage() << ")!\n" << std::endl;
+    return;
+  }
+
+  std::cerr << "\nRtApiAsio: driver reports sample rate changed to " << sRate << " ... stream stopped!!!\n" << std::endl;
+}
+
+static long asioMessages( long selector, long value, void* /*message*/, double* /*opt*/ )
+{
+  long ret = 0;
+
+  switch( selector ) {
+  case kAsioSelectorSupported:
+    if ( value == kAsioResetRequest
+         || value == kAsioEngineVersion
+         || value == kAsioResyncRequest
+         || value == kAsioLatenciesChanged
+         // The following three were added for ASIO 2.0, you don't
+         // necessarily have to support them.
+         || value == kAsioSupportsTimeInfo
+         || value == kAsioSupportsTimeCode
+         || value == kAsioSupportsInputMonitor)
+      ret = 1L;
+    break;
+  case kAsioResetRequest:
+    // Defer the task and perform the reset of the driver during the
+    // next "safe" situation.  You cannot reset the driver right now,
+    // as this code is called from the driver.  Reset the driver is
+    // done by completely destruct is. I.e. ASIOStop(),
+    // ASIODisposeBuffers(), Destruction Afterwards you initialize the
+    // driver again.
+    std::cerr << "\nRtApiAsio: driver reset requested!!!" << std::endl;
+    ret = 1L;
+    break;
+  case kAsioResyncRequest:
+    // This informs the application that the driver encountered some
+    // non-fatal data loss.  It is used for synchronization purposes
+    // of different media.  Added mainly to work around the Win16Mutex
+    // problems in Windows 95/98 with the Windows Multimedia system,
+    // which could lose data because the Mutex was held too long by
+    // another thread.  However a driver can issue it in other
+    // situations, too.
+    // std::cerr << "\nRtApiAsio: driver resync requested!!!" << std::endl;
+    asioXRun = true;
+    ret = 1L;
+    break;
+  case kAsioLatenciesChanged:
+    // This will inform the host application that the drivers were
+    // latencies changed.  Beware, it this does not mean that the
+    // buffer sizes have changed!  You might need to update internal
+    // delay data.
+    std::cerr << "\nRtApiAsio: driver latency may have changed!!!" << std::endl;
+    ret = 1L;
+    break;
+  case kAsioEngineVersion:
+    // Return the supported ASIO version of the host application.  If
+    // a host application does not implement this selector, ASIO 1.0
+    // is assumed by the driver.
+    ret = 2L;
+    break;
+  case kAsioSupportsTimeInfo:
+    // Informs the driver whether the
+    // asioCallbacks.bufferSwitchTimeInfo() callback is supported.
+    // For compatibility with ASIO 1.0 drivers the host application
+    // should always support the "old" bufferSwitch method, too.
+    ret = 0;
+    break;
+  case kAsioSupportsTimeCode:
+    // Informs the driver whether application is interested in time
+    // code info.  If an application does not need to know about time
+    // code, the driver has less work to do.
+    ret = 0;
+    break;
+  }
+  return ret;
+}
+
+static const char* getAsioErrorString( ASIOError result )
+{
+  struct Messages 
+  {
+    ASIOError value;
+    const char*message;
+  };
+
+  static const Messages m[] = 
+    {
+      {   ASE_NotPresent,    "Hardware input or output is not present or available." },
+      {   ASE_HWMalfunction,  "Hardware is malfunctioning." },
+      {   ASE_InvalidParameter, "Invalid input parameter." },
+      {   ASE_InvalidMode,      "Invalid mode." },
+      {   ASE_SPNotAdvancing,     "Sample position not advancing." },
+      {   ASE_NoClock,            "Sample clock or rate cannot be determined or is not present." },
+      {   ASE_NoMemory,           "Not enough memory to complete the request." }
+    };
+
+  for ( unsigned int i = 0; i < sizeof(m)/sizeof(m[0]); ++i )
+    if ( m[i].value == result ) return m[i].message;
+
+  return "Unknown error.";
+}
+
+//******************** End of __WINDOWS_ASIO__ *********************//
+#endif
+
+
+#if defined(__WINDOWS_WASAPI__) // Windows WASAPI API
+
+// Authored by Marcus Tomlinson <themarcustomlinson at gmail.com>, April 2014
+// - Introduces support for the Windows WASAPI API
+// - Aims to deliver bit streams to and from hardware at the lowest possible latency, via the absolute minimum buffer sizes required
+// - Provides flexible stream configuration to an otherwise strict and inflexible WASAPI interface
+// - Includes automatic internal conversion of sample rate and buffer size between hardware and the user
+
+#ifndef INITGUID
+  #define INITGUID
+#endif
+#include <audioclient.h>
+#include <avrt.h>
+#include <mmdeviceapi.h>
+#include <functiondiscoverykeys_devpkey.h>
+
+//=============================================================================
+
+#define SAFE_RELEASE( objectPtr )\
+if ( objectPtr )\
+{\
+  objectPtr->Release();\
+  objectPtr = NULL;\
+}
+
+typedef HANDLE ( __stdcall *TAvSetMmThreadCharacteristicsPtr )( LPCWSTR TaskName, LPDWORD TaskIndex );
+
+//-----------------------------------------------------------------------------
+
+// WASAPI dictates stream sample rate, format, channel count, and in some cases, buffer size.
+// Therefore we must perform all necessary conversions to user buffers in order to satisfy these
+// requirements. WasapiBuffer ring buffers are used between HwIn->UserIn and UserOut->HwOut to
+// provide intermediate storage for read / write synchronization.
+class WasapiBuffer
+{
+public:
+  WasapiBuffer()
+    : buffer_( NULL ),
+      bufferSize_( 0 ),
+      inIndex_( 0 ),
+      outIndex_( 0 ) {}
+
+  ~WasapiBuffer() {
+    free( buffer_ );
+  }
+
+  // sets the length of the internal ring buffer
+  void setBufferSize( unsigned int bufferSize, unsigned int formatBytes ) {
+    free( buffer_ );
+
+    buffer_ = ( char* ) calloc( bufferSize, formatBytes );
+
+    bufferSize_ = bufferSize;
+    inIndex_ = 0;
+    outIndex_ = 0;
+  }
+
+  // attempt to push a buffer into the ring buffer at the current "in" index
+  bool pushBuffer( char* buffer, unsigned int bufferSize, RtAudioFormat format )
+  {
+    if ( !buffer ||                 // incoming buffer is NULL
+         bufferSize == 0 ||         // incoming buffer has no data
+         bufferSize > bufferSize_ ) // incoming buffer too large
+    {
+      return false;
+    }
+
+    unsigned int relOutIndex = outIndex_;
+    unsigned int inIndexEnd = inIndex_ + bufferSize;
+    if ( relOutIndex < inIndex_ && inIndexEnd >= bufferSize_ ) {
+      relOutIndex += bufferSize_;
+    }
+
+    // "in" index can end on the "out" index but cannot begin at it
+    if ( inIndex_ <= relOutIndex && inIndexEnd > relOutIndex ) {
+      return false; // not enough space between "in" index and "out" index
+    }
+
+    // copy buffer from external to internal
+    int fromZeroSize = inIndex_ + bufferSize - bufferSize_;
+    fromZeroSize = fromZeroSize < 0 ? 0 : fromZeroSize;
+    int fromInSize = bufferSize - fromZeroSize;
+
+    switch( format )
+      {
+      case RTAUDIO_SINT8:
+        memcpy( &( ( char* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( char ) );
+        memcpy( buffer_, &( ( char* ) buffer )[fromInSize], fromZeroSize * sizeof( char ) );
+        break;
+      case RTAUDIO_SINT16:
+        memcpy( &( ( short* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( short ) );
+        memcpy( buffer_, &( ( short* ) buffer )[fromInSize], fromZeroSize * sizeof( short ) );
+        break;
+      case RTAUDIO_SINT24:
+        memcpy( &( ( S24* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( S24 ) );
+        memcpy( buffer_, &( ( S24* ) buffer )[fromInSize], fromZeroSize * sizeof( S24 ) );
+        break;
+      case RTAUDIO_SINT32:
+        memcpy( &( ( int* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( int ) );
+        memcpy( buffer_, &( ( int* ) buffer )[fromInSize], fromZeroSize * sizeof( int ) );
+        break;
+      case RTAUDIO_FLOAT32:
+        memcpy( &( ( float* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( float ) );
+        memcpy( buffer_, &( ( float* ) buffer )[fromInSize], fromZeroSize * sizeof( float ) );
+        break;
+      case RTAUDIO_FLOAT64:
+        memcpy( &( ( double* ) buffer_ )[inIndex_], buffer, fromInSize * sizeof( double ) );
+        memcpy( buffer_, &( ( double* ) buffer )[fromInSize], fromZeroSize * sizeof( double ) );
+        break;
+    }
+
+    // update "in" index
+    inIndex_ += bufferSize;
+    inIndex_ %= bufferSize_;
+
+    return true;
+  }
+
+  // attempt to pull a buffer from the ring buffer from the current "out" index
+  bool pullBuffer( char* buffer, unsigned int bufferSize, RtAudioFormat format )
+  {
+    if ( !buffer ||                 // incoming buffer is NULL
+         bufferSize == 0 ||         // incoming buffer has no data
+         bufferSize > bufferSize_ ) // incoming buffer too large
+    {
+      return false;
+    }
+
+    unsigned int relInIndex = inIndex_;
+    unsigned int outIndexEnd = outIndex_ + bufferSize;
+    if ( relInIndex < outIndex_ && outIndexEnd >= bufferSize_ ) {
+      relInIndex += bufferSize_;
+    }
+
+    // "out" index can begin at and end on the "in" index
+    if ( outIndex_ < relInIndex && outIndexEnd > relInIndex ) {
+      return false; // not enough space between "out" index and "in" index
+    }
+
+    // copy buffer from internal to external
+    int fromZeroSize = outIndex_ + bufferSize - bufferSize_;
+    fromZeroSize = fromZeroSize < 0 ? 0 : fromZeroSize;
+    int fromOutSize = bufferSize - fromZeroSize;
+
+    switch( format )
+    {
+      case RTAUDIO_SINT8:
+        memcpy( buffer, &( ( char* ) buffer_ )[outIndex_], fromOutSize * sizeof( char ) );
+        memcpy( &( ( char* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( char ) );
+        break;
+      case RTAUDIO_SINT16:
+        memcpy( buffer, &( ( short* ) buffer_ )[outIndex_], fromOutSize * sizeof( short ) );
+        memcpy( &( ( short* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( short ) );
+        break;
+      case RTAUDIO_SINT24:
+        memcpy( buffer, &( ( S24* ) buffer_ )[outIndex_], fromOutSize * sizeof( S24 ) );
+        memcpy( &( ( S24* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( S24 ) );
+        break;
+      case RTAUDIO_SINT32:
+        memcpy( buffer, &( ( int* ) buffer_ )[outIndex_], fromOutSize * sizeof( int ) );
+        memcpy( &( ( int* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( int ) );
+        break;
+      case RTAUDIO_FLOAT32:
+        memcpy( buffer, &( ( float* ) buffer_ )[outIndex_], fromOutSize * sizeof( float ) );
+        memcpy( &( ( float* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( float ) );
+        break;
+      case RTAUDIO_FLOAT64:
+        memcpy( buffer, &( ( double* ) buffer_ )[outIndex_], fromOutSize * sizeof( double ) );
+        memcpy( &( ( double* ) buffer )[fromOutSize], buffer_, fromZeroSize * sizeof( double ) );
+        break;
+    }
+
+    // update "out" index
+    outIndex_ += bufferSize;
+    outIndex_ %= bufferSize_;
+
+    return true;
+  }
+
+private:
+  char* buffer_;
+  unsigned int bufferSize_;
+  unsigned int inIndex_;
+  unsigned int outIndex_;
+};
+
+//-----------------------------------------------------------------------------
+
+// In order to satisfy WASAPI's buffer requirements, we need a means of converting sample rate
+// between HW and the user. The convertBufferWasapi function is used to perform this conversion
+// between HwIn->UserIn and UserOut->HwOut during the stream callback loop.
+// This sample rate converter favors speed over quality, and works best with conversions between
+// one rate and its multiple.
+void convertBufferWasapi( char* outBuffer,
+                          const char* inBuffer,
+                          const unsigned int& channelCount,
+                          const unsigned int& inSampleRate,
+                          const unsigned int& outSampleRate,
+                          const unsigned int& inSampleCount,
+                          unsigned int& outSampleCount,
+                          const RtAudioFormat& format )
+{
+  // calculate the new outSampleCount and relative sampleStep
+  float sampleRatio = ( float ) outSampleRate / inSampleRate;
+  float sampleStep = 1.0f / sampleRatio;
+  float inSampleFraction = 0.0f;
+
+  outSampleCount = ( unsigned int ) roundf( inSampleCount * sampleRatio );
+
+  // frame-by-frame, copy each relative input sample into it's corresponding output sample
+  for ( unsigned int outSample = 0; outSample < outSampleCount; outSample++ )
+  {
+    unsigned int inSample = ( unsigned int ) inSampleFraction;
+
+    switch ( format )
+    {
+      case RTAUDIO_SINT8:
+        memcpy( &( ( char* ) outBuffer )[ outSample * channelCount ], &( ( char* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( char ) );
+        break;
+      case RTAUDIO_SINT16:
+        memcpy( &( ( short* ) outBuffer )[ outSample * channelCount ], &( ( short* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( short ) );
+        break;
+      case RTAUDIO_SINT24:
+        memcpy( &( ( S24* ) outBuffer )[ outSample * channelCount ], &( ( S24* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( S24 ) );
+        break;
+      case RTAUDIO_SINT32:
+        memcpy( &( ( int* ) outBuffer )[ outSample * channelCount ], &( ( int* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( int ) );
+        break;
+      case RTAUDIO_FLOAT32:
+        memcpy( &( ( float* ) outBuffer )[ outSample * channelCount ], &( ( float* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( float ) );
+        break;
+      case RTAUDIO_FLOAT64:
+        memcpy( &( ( double* ) outBuffer )[ outSample * channelCount ], &( ( double* ) inBuffer )[ inSample * channelCount ], channelCount * sizeof( double ) );
+        break;
+    }
+
+    // jump to next in sample
+    inSampleFraction += sampleStep;
+  }
+}
+
+//-----------------------------------------------------------------------------
+
+// A structure to hold various information related to the WASAPI implementation.
+struct WasapiHandle
+{
+  IAudioClient* captureAudioClient;
+  IAudioClient* renderAudioClient;
+  IAudioCaptureClient* captureClient;
+  IAudioRenderClient* renderClient;
+  HANDLE captureEvent;
+  HANDLE renderEvent;
+
+  WasapiHandle()
+  : captureAudioClient( NULL ),
+    renderAudioClient( NULL ),
+    captureClient( NULL ),
+    renderClient( NULL ),
+    captureEvent( NULL ),
+    renderEvent( NULL ) {}
+};
+
+//=============================================================================
+
+RtApiWasapi::RtApiWasapi()
+  : coInitialized_( false ), deviceEnumerator_( NULL )
+{
+  // WASAPI can run either apartment or multi-threaded
+  HRESULT hr = CoInitialize( NULL );
+  if ( !FAILED( hr ) )
+    coInitialized_ = true;
+
+  // Instantiate device enumerator
+  hr = CoCreateInstance( __uuidof( MMDeviceEnumerator ), NULL,
+                         CLSCTX_ALL, __uuidof( IMMDeviceEnumerator ),
+                         ( void** ) &deviceEnumerator_ );
+
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::RtApiWasapi: Unable to instantiate device enumerator";
+    error( RtAudioError::DRIVER_ERROR );
+  }
+}
+
+//-----------------------------------------------------------------------------
+
+RtApiWasapi::~RtApiWasapi()
+{
+  if ( stream_.state != STREAM_CLOSED )
+    closeStream();
+
+  SAFE_RELEASE( deviceEnumerator_ );
+
+  // If this object previously called CoInitialize()
+  if ( coInitialized_ )
+    CoUninitialize();
+}
+
+//=============================================================================
+
+unsigned int RtApiWasapi::getDeviceCount( void )
+{
+  unsigned int captureDeviceCount = 0;
+  unsigned int renderDeviceCount = 0;
+
+  IMMDeviceCollection* captureDevices = NULL;
+  IMMDeviceCollection* renderDevices = NULL;
+
+  // Count capture devices
+  errorText_.clear();
+  HRESULT hr = deviceEnumerator_->EnumAudioEndpoints( eCapture, DEVICE_STATE_ACTIVE, &captureDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceCount: Unable to retrieve capture device collection.";
+    goto Exit;
+  }
+
+  hr = captureDevices->GetCount( &captureDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceCount: Unable to retrieve capture device count.";
+    goto Exit;
+  }
+
+  // Count render devices
+  hr = deviceEnumerator_->EnumAudioEndpoints( eRender, DEVICE_STATE_ACTIVE, &renderDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceCount: Unable to retrieve render device collection.";
+    goto Exit;
+  }
+
+  hr = renderDevices->GetCount( &renderDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceCount: Unable to retrieve render device count.";
+    goto Exit;
+  }
+
+Exit:
+  // release all references
+  SAFE_RELEASE( captureDevices );
+  SAFE_RELEASE( renderDevices );
+
+  if ( errorText_.empty() )
+    return captureDeviceCount + renderDeviceCount;
+
+  error( RtAudioError::DRIVER_ERROR );
+  return 0;
+}
+
+//-----------------------------------------------------------------------------
+
+RtAudio::DeviceInfo RtApiWasapi::getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  unsigned int captureDeviceCount = 0;
+  unsigned int renderDeviceCount = 0;
+  std::string defaultDeviceName;
+  bool isCaptureDevice = false;
+
+  PROPVARIANT deviceNameProp;
+  PROPVARIANT defaultDeviceNameProp;
+
+  IMMDeviceCollection* captureDevices = NULL;
+  IMMDeviceCollection* renderDevices = NULL;
+  IMMDevice* devicePtr = NULL;
+  IMMDevice* defaultDevicePtr = NULL;
+  IAudioClient* audioClient = NULL;
+  IPropertyStore* devicePropStore = NULL;
+  IPropertyStore* defaultDevicePropStore = NULL;
+
+  WAVEFORMATEX* deviceFormat = NULL;
+  WAVEFORMATEX* closestMatchFormat = NULL;
+
+  // probed
+  info.probed = false;
+
+  // Count capture devices
+  errorText_.clear();
+  RtAudioError::Type errorType = RtAudioError::DRIVER_ERROR;
+  HRESULT hr = deviceEnumerator_->EnumAudioEndpoints( eCapture, DEVICE_STATE_ACTIVE, &captureDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve capture device collection.";
+    goto Exit;
+  }
+
+  hr = captureDevices->GetCount( &captureDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve capture device count.";
+    goto Exit;
+  }
+
+  // Count render devices
+  hr = deviceEnumerator_->EnumAudioEndpoints( eRender, DEVICE_STATE_ACTIVE, &renderDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve render device collection.";
+    goto Exit;
+  }
+
+  hr = renderDevices->GetCount( &renderDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve render device count.";
+    goto Exit;
+  }
+
+  // validate device index
+  if ( device >= captureDeviceCount + renderDeviceCount ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Invalid device index.";
+    errorType = RtAudioError::INVALID_USE;
+    goto Exit;
+  }
+
+  // determine whether index falls within capture or render devices
+  if ( device >= renderDeviceCount ) {
+    hr = captureDevices->Item( device - renderDeviceCount, &devicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve capture device handle.";
+      goto Exit;
+    }
+    isCaptureDevice = true;
+  }
+  else {
+    hr = renderDevices->Item( device, &devicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve render device handle.";
+      goto Exit;
+    }
+    isCaptureDevice = false;
+  }
+
+  // get default device name
+  if ( isCaptureDevice ) {
+    hr = deviceEnumerator_->GetDefaultAudioEndpoint( eCapture, eConsole, &defaultDevicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve default capture device handle.";
+      goto Exit;
+    }
+  }
+  else {
+    hr = deviceEnumerator_->GetDefaultAudioEndpoint( eRender, eConsole, &defaultDevicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve default render device handle.";
+      goto Exit;
+    }
+  }
+
+  hr = defaultDevicePtr->OpenPropertyStore( STGM_READ, &defaultDevicePropStore );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to open default device property store.";
+    goto Exit;
+  }
+  PropVariantInit( &defaultDeviceNameProp );
+
+  hr = defaultDevicePropStore->GetValue( PKEY_Device_FriendlyName, &defaultDeviceNameProp );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve default device property: PKEY_Device_FriendlyName.";
+    goto Exit;
+  }
+
+  defaultDeviceName = convertCharPointerToStdString(defaultDeviceNameProp.pwszVal);
+
+  // name
+  hr = devicePtr->OpenPropertyStore( STGM_READ, &devicePropStore );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to open device property store.";
+    goto Exit;
+  }
+
+  PropVariantInit( &deviceNameProp );
+
+  hr = devicePropStore->GetValue( PKEY_Device_FriendlyName, &deviceNameProp );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve device property: PKEY_Device_FriendlyName.";
+    goto Exit;
+  }
+
+  info.name =convertCharPointerToStdString(deviceNameProp.pwszVal);
+
+  // is default
+  if ( isCaptureDevice ) {
+    info.isDefaultInput = info.name == defaultDeviceName;
+    info.isDefaultOutput = false;
+  }
+  else {
+    info.isDefaultInput = false;
+    info.isDefaultOutput = info.name == defaultDeviceName;
+  }
+
+  // channel count
+  hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL, NULL, ( void** ) &audioClient );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve device audio client.";
+    goto Exit;
+  }
+
+  hr = audioClient->GetMixFormat( &deviceFormat );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::getDeviceInfo: Unable to retrieve device mix format.";
+    goto Exit;
+  }
+
+  if ( isCaptureDevice ) {
+    info.inputChannels = deviceFormat->nChannels;
+    info.outputChannels = 0;
+    info.duplexChannels = 0;
+  }
+  else {
+    info.inputChannels = 0;
+    info.outputChannels = deviceFormat->nChannels;
+    info.duplexChannels = 0;
+  }
+
+  // sample rates
+  info.sampleRates.clear();
+
+  // allow support for all sample rates as we have a built-in sample rate converter
+  for ( unsigned int i = 0; i < MAX_SAMPLE_RATES; i++ ) {
+    info.sampleRates.push_back( SAMPLE_RATES[i] );
+  }
+  info.preferredSampleRate = deviceFormat->nSamplesPerSec;
+
+  // native format
+  info.nativeFormats = 0;
+
+  if ( deviceFormat->wFormatTag == WAVE_FORMAT_IEEE_FLOAT ||
+       ( deviceFormat->wFormatTag == WAVE_FORMAT_EXTENSIBLE &&
+         ( ( WAVEFORMATEXTENSIBLE* ) deviceFormat )->SubFormat == KSDATAFORMAT_SUBTYPE_IEEE_FLOAT ) )
+  {
+    if ( deviceFormat->wBitsPerSample == 32 ) {
+      info.nativeFormats |= RTAUDIO_FLOAT32;
+    }
+    else if ( deviceFormat->wBitsPerSample == 64 ) {
+      info.nativeFormats |= RTAUDIO_FLOAT64;
+    }
+  }
+  else if ( deviceFormat->wFormatTag == WAVE_FORMAT_PCM ||
+           ( deviceFormat->wFormatTag == WAVE_FORMAT_EXTENSIBLE &&
+             ( ( WAVEFORMATEXTENSIBLE* ) deviceFormat )->SubFormat == KSDATAFORMAT_SUBTYPE_PCM ) )
+  {
+    if ( deviceFormat->wBitsPerSample == 8 ) {
+      info.nativeFormats |= RTAUDIO_SINT8;
+    }
+    else if ( deviceFormat->wBitsPerSample == 16 ) {
+      info.nativeFormats |= RTAUDIO_SINT16;
+    }
+    else if ( deviceFormat->wBitsPerSample == 24 ) {
+      info.nativeFormats |= RTAUDIO_SINT24;
+    }
+    else if ( deviceFormat->wBitsPerSample == 32 ) {
+      info.nativeFormats |= RTAUDIO_SINT32;
+    }
+  }
+
+  // probed
+  info.probed = true;
+
+Exit:
+  // release all references
+  PropVariantClear( &deviceNameProp );
+  PropVariantClear( &defaultDeviceNameProp );
+
+  SAFE_RELEASE( captureDevices );
+  SAFE_RELEASE( renderDevices );
+  SAFE_RELEASE( devicePtr );
+  SAFE_RELEASE( defaultDevicePtr );
+  SAFE_RELEASE( audioClient );
+  SAFE_RELEASE( devicePropStore );
+  SAFE_RELEASE( defaultDevicePropStore );
+
+  CoTaskMemFree( deviceFormat );
+  CoTaskMemFree( closestMatchFormat );
+
+  if ( !errorText_.empty() )
+    error( errorType );
+  return info;
+}
+
+//-----------------------------------------------------------------------------
+
+unsigned int RtApiWasapi::getDefaultOutputDevice( void )
+{
+  for ( unsigned int i = 0; i < getDeviceCount(); i++ ) {
+    if ( getDeviceInfo( i ).isDefaultOutput ) {
+      return i;
+    }
+  }
+
+  return 0;
+}
+
+//-----------------------------------------------------------------------------
+
+unsigned int RtApiWasapi::getDefaultInputDevice( void )
+{
+  for ( unsigned int i = 0; i < getDeviceCount(); i++ ) {
+    if ( getDeviceInfo( i ).isDefaultInput ) {
+      return i;
+    }
+  }
+
+  return 0;
+}
+
+//-----------------------------------------------------------------------------
+
+void RtApiWasapi::closeStream( void )
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiWasapi::closeStream: No open stream to close.";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  if ( stream_.state != STREAM_STOPPED )
+    stopStream();
+
+  // clean up stream memory
+  SAFE_RELEASE( ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient )
+  SAFE_RELEASE( ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient )
+
+  SAFE_RELEASE( ( ( WasapiHandle* ) stream_.apiHandle )->captureClient )
+  SAFE_RELEASE( ( ( WasapiHandle* ) stream_.apiHandle )->renderClient )
+
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent )
+    CloseHandle( ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent );
+
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->renderEvent )
+    CloseHandle( ( ( WasapiHandle* ) stream_.apiHandle )->renderEvent );
+
+  delete ( WasapiHandle* ) stream_.apiHandle;
+  stream_.apiHandle = NULL;
+
+  for ( int i = 0; i < 2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  // update stream state
+  stream_.state = STREAM_CLOSED;
+}
+
+//-----------------------------------------------------------------------------
+
+void RtApiWasapi::startStream( void )
+{
+  verifyStream();
+
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiWasapi::startStream: The stream is already running.";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // update stream state
+  stream_.state = STREAM_RUNNING;
+
+  // create WASAPI stream thread
+  stream_.callbackInfo.thread = ( ThreadHandle ) CreateThread( NULL, 0, runWasapiThread, this, CREATE_SUSPENDED, NULL );
+
+  if ( !stream_.callbackInfo.thread ) {
+    errorText_ = "RtApiWasapi::startStream: Unable to instantiate callback thread.";
+    error( RtAudioError::THREAD_ERROR );
+  }
+  else {
+    SetThreadPriority( ( void* ) stream_.callbackInfo.thread, stream_.callbackInfo.priority );
+    ResumeThread( ( void* ) stream_.callbackInfo.thread );
+  }
+}
+
+//-----------------------------------------------------------------------------
+
+void RtApiWasapi::stopStream( void )
+{
+  verifyStream();
+
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiWasapi::stopStream: The stream is already stopped.";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // inform stream thread by setting stream state to STREAM_STOPPING
+  stream_.state = STREAM_STOPPING;
+
+  // wait until stream thread is stopped
+  while( stream_.state != STREAM_STOPPED ) {
+    Sleep( 1 );
+  }
+
+  // Wait for the last buffer to play before stopping.
+  Sleep( 1000 * stream_.bufferSize / stream_.sampleRate );
+
+  // stop capture client if applicable
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient ) {
+    HRESULT hr = ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient->Stop();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::stopStream: Unable to stop capture stream.";
+      error( RtAudioError::DRIVER_ERROR );
+      return;
+    }
+  }
+
+  // stop render client if applicable
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient ) {
+    HRESULT hr = ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient->Stop();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::stopStream: Unable to stop render stream.";
+      error( RtAudioError::DRIVER_ERROR );
+      return;
+    }
+  }
+
+  // close thread handle
+  if ( stream_.callbackInfo.thread && !CloseHandle( ( void* ) stream_.callbackInfo.thread ) ) {
+    errorText_ = "RtApiWasapi::stopStream: Unable to close callback thread.";
+    error( RtAudioError::THREAD_ERROR );
+    return;
+  }
+
+  stream_.callbackInfo.thread = (ThreadHandle) NULL;
+}
+
+//-----------------------------------------------------------------------------
+
+void RtApiWasapi::abortStream( void )
+{
+  verifyStream();
+
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiWasapi::abortStream: The stream is already stopped.";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // inform stream thread by setting stream state to STREAM_STOPPING
+  stream_.state = STREAM_STOPPING;
+
+  // wait until stream thread is stopped
+  while ( stream_.state != STREAM_STOPPED ) {
+    Sleep( 1 );
+  }
+
+  // stop capture client if applicable
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient ) {
+    HRESULT hr = ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient->Stop();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::abortStream: Unable to stop capture stream.";
+      error( RtAudioError::DRIVER_ERROR );
+      return;
+    }
+  }
+
+  // stop render client if applicable
+  if ( ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient ) {
+    HRESULT hr = ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient->Stop();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::abortStream: Unable to stop render stream.";
+      error( RtAudioError::DRIVER_ERROR );
+      return;
+    }
+  }
+
+  // close thread handle
+  if ( stream_.callbackInfo.thread && !CloseHandle( ( void* ) stream_.callbackInfo.thread ) ) {
+    errorText_ = "RtApiWasapi::abortStream: Unable to close callback thread.";
+    error( RtAudioError::THREAD_ERROR );
+    return;
+  }
+
+  stream_.callbackInfo.thread = (ThreadHandle) NULL;
+}
+
+//-----------------------------------------------------------------------------
+
+bool RtApiWasapi::probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                   unsigned int firstChannel, unsigned int sampleRate,
+                                   RtAudioFormat format, unsigned int* bufferSize,
+                                   RtAudio::StreamOptions* options )
+{
+  bool methodResult = FAILURE;
+  unsigned int captureDeviceCount = 0;
+  unsigned int renderDeviceCount = 0;
+
+  IMMDeviceCollection* captureDevices = NULL;
+  IMMDeviceCollection* renderDevices = NULL;
+  IMMDevice* devicePtr = NULL;
+  WAVEFORMATEX* deviceFormat = NULL;
+  unsigned int bufferBytes;
+  stream_.state = STREAM_STOPPED;
+
+  // create API Handle if not already created
+  if ( !stream_.apiHandle )
+    stream_.apiHandle = ( void* ) new WasapiHandle();
+
+  // Count capture devices
+  errorText_.clear();
+  RtAudioError::Type errorType = RtAudioError::DRIVER_ERROR;
+  HRESULT hr = deviceEnumerator_->EnumAudioEndpoints( eCapture, DEVICE_STATE_ACTIVE, &captureDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve capture device collection.";
+    goto Exit;
+  }
+
+  hr = captureDevices->GetCount( &captureDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve capture device count.";
+    goto Exit;
+  }
+
+  // Count render devices
+  hr = deviceEnumerator_->EnumAudioEndpoints( eRender, DEVICE_STATE_ACTIVE, &renderDevices );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device collection.";
+    goto Exit;
+  }
+
+  hr = renderDevices->GetCount( &renderDeviceCount );
+  if ( FAILED( hr ) ) {
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device count.";
+    goto Exit;
+  }
+
+  // validate device index
+  if ( device >= captureDeviceCount + renderDeviceCount ) {
+    errorType = RtAudioError::INVALID_USE;
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Invalid device index.";
+    goto Exit;
+  }
+
+  // determine whether index falls within capture or render devices
+  if ( device >= renderDeviceCount ) {
+    if ( mode != INPUT ) {
+      errorType = RtAudioError::INVALID_USE;
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Capture device selected as output device.";
+      goto Exit;
+    }
+
+    // retrieve captureAudioClient from devicePtr
+    IAudioClient*& captureAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient;
+
+    hr = captureDevices->Item( device - renderDeviceCount, &devicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve capture device handle.";
+      goto Exit;
+    }
+
+    hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL,
+                              NULL, ( void** ) &captureAudioClient );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device audio client.";
+      goto Exit;
+    }
+
+    hr = captureAudioClient->GetMixFormat( &deviceFormat );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device mix format.";
+      goto Exit;
+    }
+
+    stream_.nDeviceChannels[mode] = deviceFormat->nChannels;
+    captureAudioClient->GetStreamLatency( ( long long* ) &stream_.latency[mode] );
+  }
+  else {
+    if ( mode != OUTPUT ) {
+      errorType = RtAudioError::INVALID_USE;
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Render device selected as input device.";
+      goto Exit;
+    }
+
+    // retrieve renderAudioClient from devicePtr
+    IAudioClient*& renderAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient;
+
+    hr = renderDevices->Item( device, &devicePtr );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device handle.";
+      goto Exit;
+    }
+
+    hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL,
+                              NULL, ( void** ) &renderAudioClient );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device audio client.";
+      goto Exit;
+    }
+
+    hr = renderAudioClient->GetMixFormat( &deviceFormat );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device mix format.";
+      goto Exit;
+    }
+
+    stream_.nDeviceChannels[mode] = deviceFormat->nChannels;
+    renderAudioClient->GetStreamLatency( ( long long* ) &stream_.latency[mode] );
+  }
+
+  // fill stream data
+  if ( ( stream_.mode == OUTPUT && mode == INPUT ) ||
+       ( stream_.mode == INPUT && mode == OUTPUT ) ) {
+    stream_.mode = DUPLEX;
+  }
+  else {
+    stream_.mode = mode;
+  }
+
+  stream_.device[mode] = device;
+  stream_.doByteSwap[mode] = false;
+  stream_.sampleRate = sampleRate;
+  stream_.bufferSize = *bufferSize;
+  stream_.nBuffers = 1;
+  stream_.nUserChannels[mode] = channels;
+  stream_.channelOffset[mode] = firstChannel;
+  stream_.userFormat = format;
+  stream_.deviceFormat[mode] = getDeviceInfo( device ).nativeFormats;
+
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED )
+    stream_.userInterleaved = false;
+  else
+    stream_.userInterleaved = true;
+  stream_.deviceInterleaved[mode] = true;
+
+  // Set flags for buffer conversion.
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] ||
+       stream_.nUserChannels != stream_.nDeviceChannels )
+    stream_.doConvertBuffer[mode] = true;
+  else if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+            stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  if ( stream_.doConvertBuffer[mode] )
+    setConvertInfo( mode, 0 );
+
+  // Allocate necessary internal buffers
+  bufferBytes = stream_.nUserChannels[mode] * stream_.bufferSize * formatBytes( stream_.userFormat );
+
+  stream_.userBuffer[mode] = ( char* ) calloc( bufferBytes, 1 );
+  if ( !stream_.userBuffer[mode] ) {
+    errorType = RtAudioError::MEMORY_ERROR;
+    errorText_ = "RtApiWasapi::probeDeviceOpen: Error allocating user buffer memory.";
+    goto Exit;
+  }
+
+  if ( options && options->flags & RTAUDIO_SCHEDULE_REALTIME )
+    stream_.callbackInfo.priority = 15;
+  else
+    stream_.callbackInfo.priority = 0;
+
+  ///! TODO: RTAUDIO_MINIMIZE_LATENCY // Provide stream buffers directly to callback
+  ///! TODO: RTAUDIO_HOG_DEVICE       // Exclusive mode
+
+  methodResult = SUCCESS;
+
+Exit:
+  //clean up
+  SAFE_RELEASE( captureDevices );
+  SAFE_RELEASE( renderDevices );
+  SAFE_RELEASE( devicePtr );
+  CoTaskMemFree( deviceFormat );
+
+  // if method failed, close the stream
+  if ( methodResult == FAILURE )
+    closeStream();
+
+  if ( !errorText_.empty() )
+    error( errorType );
+  return methodResult;
+}
+
+//=============================================================================
+
+DWORD WINAPI RtApiWasapi::runWasapiThread( void* wasapiPtr )
+{
+  if ( wasapiPtr )
+    ( ( RtApiWasapi* ) wasapiPtr )->wasapiThread();
+
+  return 0;
+}
+
+DWORD WINAPI RtApiWasapi::stopWasapiThread( void* wasapiPtr )
+{
+  if ( wasapiPtr )
+    ( ( RtApiWasapi* ) wasapiPtr )->stopStream();
+
+  return 0;
+}
+
+DWORD WINAPI RtApiWasapi::abortWasapiThread( void* wasapiPtr )
+{
+  if ( wasapiPtr )
+    ( ( RtApiWasapi* ) wasapiPtr )->abortStream();
+
+  return 0;
+}
+
+//-----------------------------------------------------------------------------
+
+void RtApiWasapi::wasapiThread()
+{
+  // as this is a new thread, we must CoInitialize it
+  CoInitialize( NULL );
+
+  HRESULT hr;
+
+  IAudioClient* captureAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient;
+  IAudioClient* renderAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient;
+  IAudioCaptureClient* captureClient = ( ( WasapiHandle* ) stream_.apiHandle )->captureClient;
+  IAudioRenderClient* renderClient = ( ( WasapiHandle* ) stream_.apiHandle )->renderClient;
+  HANDLE captureEvent = ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent;
+  HANDLE renderEvent = ( ( WasapiHandle* ) stream_.apiHandle )->renderEvent;
+
+  WAVEFORMATEX* captureFormat = NULL;
+  WAVEFORMATEX* renderFormat = NULL;
+  float captureSrRatio = 0.0f;
+  float renderSrRatio = 0.0f;
+  WasapiBuffer captureBuffer;
+  WasapiBuffer renderBuffer;
+
+  // declare local stream variables
+  RtAudioCallback callback = ( RtAudioCallback ) stream_.callbackInfo.callback;
+  BYTE* streamBuffer = NULL;
+  unsigned long captureFlags = 0;
+  unsigned int bufferFrameCount = 0;
+  unsigned int numFramesPadding = 0;
+  unsigned int convBufferSize = 0;
+  bool callbackPushed = false;
+  bool callbackPulled = false;
+  bool callbackStopped = false;
+  int callbackResult = 0;
+
+  // convBuffer is used to store converted buffers between WASAPI and the user
+  char* convBuffer = NULL;
+  unsigned int convBuffSize = 0;
+  unsigned int deviceBuffSize = 0;
+
+  errorText_.clear();
+  RtAudioError::Type errorType = RtAudioError::DRIVER_ERROR;
+
+  // Attempt to assign "Pro Audio" characteristic to thread
+  HMODULE AvrtDll = LoadLibrary( (LPCTSTR) "AVRT.dll" );
+  if ( AvrtDll ) {
+    DWORD taskIndex = 0;
+    TAvSetMmThreadCharacteristicsPtr AvSetMmThreadCharacteristicsPtr = ( TAvSetMmThreadCharacteristicsPtr ) GetProcAddress( AvrtDll, "AvSetMmThreadCharacteristicsW" );
+    AvSetMmThreadCharacteristicsPtr( L"Pro Audio", &taskIndex );
+    FreeLibrary( AvrtDll );
+  }
+
+  // start capture stream if applicable
+  if ( captureAudioClient ) {
+    hr = captureAudioClient->GetMixFormat( &captureFormat );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve device mix format.";
+      goto Exit;
+    }
+
+    captureSrRatio = ( ( float ) captureFormat->nSamplesPerSec / stream_.sampleRate );
+
+    // initialize capture stream according to desire buffer size
+    float desiredBufferSize = stream_.bufferSize * captureSrRatio;
+    REFERENCE_TIME desiredBufferPeriod = ( REFERENCE_TIME ) ( ( float ) desiredBufferSize * 10000000 / captureFormat->nSamplesPerSec );
+
+    if ( !captureClient ) {
+      hr = captureAudioClient->Initialize( AUDCLNT_SHAREMODE_SHARED,
+                                           AUDCLNT_STREAMFLAGS_EVENTCALLBACK,
+                                           desiredBufferPeriod,
+                                           desiredBufferPeriod,
+                                           captureFormat,
+                                           NULL );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to initialize capture audio client.";
+        goto Exit;
+      }
+
+      hr = captureAudioClient->GetService( __uuidof( IAudioCaptureClient ),
+                                           ( void** ) &captureClient );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve capture client handle.";
+        goto Exit;
+      }
+
+      // configure captureEvent to trigger on every available capture buffer
+      captureEvent = CreateEvent( NULL, FALSE, FALSE, NULL );
+      if ( !captureEvent ) {
+        errorType = RtAudioError::SYSTEM_ERROR;
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to create capture event.";
+        goto Exit;
+      }
+
+      hr = captureAudioClient->SetEventHandle( captureEvent );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to set capture event handle.";
+        goto Exit;
+      }
+
+      ( ( WasapiHandle* ) stream_.apiHandle )->captureClient = captureClient;
+      ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent = captureEvent;
+    }
+
+    unsigned int inBufferSize = 0;
+    hr = captureAudioClient->GetBufferSize( &inBufferSize );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to get capture buffer size.";
+      goto Exit;
+    }
+
+    // scale outBufferSize according to stream->user sample rate ratio
+    unsigned int outBufferSize = ( unsigned int ) ( stream_.bufferSize * captureSrRatio ) * stream_.nDeviceChannels[INPUT];
+    inBufferSize *= stream_.nDeviceChannels[INPUT];
+
+    // set captureBuffer size
+    captureBuffer.setBufferSize( inBufferSize + outBufferSize, formatBytes( stream_.deviceFormat[INPUT] ) );
+
+    // reset the capture stream
+    hr = captureAudioClient->Reset();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to reset capture stream.";
+      goto Exit;
+    }
+
+    // start the capture stream
+    hr = captureAudioClient->Start();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to start capture stream.";
+      goto Exit;
+    }
+  }
+
+  // start render stream if applicable
+  if ( renderAudioClient ) {
+    hr = renderAudioClient->GetMixFormat( &renderFormat );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve device mix format.";
+      goto Exit;
+    }
+
+    renderSrRatio = ( ( float ) renderFormat->nSamplesPerSec / stream_.sampleRate );
+
+    // initialize render stream according to desire buffer size
+    float desiredBufferSize = stream_.bufferSize * renderSrRatio;
+    REFERENCE_TIME desiredBufferPeriod = ( REFERENCE_TIME ) ( ( float ) desiredBufferSize * 10000000 / renderFormat->nSamplesPerSec );
+
+    if ( !renderClient ) {
+      hr = renderAudioClient->Initialize( AUDCLNT_SHAREMODE_SHARED,
+                                          AUDCLNT_STREAMFLAGS_EVENTCALLBACK,
+                                          desiredBufferPeriod,
+                                          desiredBufferPeriod,
+                                          renderFormat,
+                                          NULL );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to initialize render audio client.";
+        goto Exit;
+      }
+
+      hr = renderAudioClient->GetService( __uuidof( IAudioRenderClient ),
+                                          ( void** ) &renderClient );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve render client handle.";
+        goto Exit;
+      }
+
+      // configure renderEvent to trigger on every available render buffer
+      renderEvent = CreateEvent( NULL, FALSE, FALSE, NULL );
+      if ( !renderEvent ) {
+        errorType = RtAudioError::SYSTEM_ERROR;
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to create render event.";
+        goto Exit;
+      }
+
+      hr = renderAudioClient->SetEventHandle( renderEvent );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to set render event handle.";
+        goto Exit;
+      }
+
+      ( ( WasapiHandle* ) stream_.apiHandle )->renderClient = renderClient;
+      ( ( WasapiHandle* ) stream_.apiHandle )->renderEvent = renderEvent;
+    }
+
+    unsigned int outBufferSize = 0;
+    hr = renderAudioClient->GetBufferSize( &outBufferSize );
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to get render buffer size.";
+      goto Exit;
+    }
+
+    // scale inBufferSize according to user->stream sample rate ratio
+    unsigned int inBufferSize = ( unsigned int ) ( stream_.bufferSize * renderSrRatio ) * stream_.nDeviceChannels[OUTPUT];
+    outBufferSize *= stream_.nDeviceChannels[OUTPUT];
+
+    // set renderBuffer size
+    renderBuffer.setBufferSize( inBufferSize + outBufferSize, formatBytes( stream_.deviceFormat[OUTPUT] ) );
+
+    // reset the render stream
+    hr = renderAudioClient->Reset();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to reset render stream.";
+      goto Exit;
+    }
+
+    // start the render stream
+    hr = renderAudioClient->Start();
+    if ( FAILED( hr ) ) {
+      errorText_ = "RtApiWasapi::wasapiThread: Unable to start render stream.";
+      goto Exit;
+    }
+  }
+
+  if ( stream_.mode == INPUT ) {
+    convBuffSize = ( size_t ) ( stream_.bufferSize * captureSrRatio ) * stream_.nDeviceChannels[INPUT] * formatBytes( stream_.deviceFormat[INPUT] );
+    deviceBuffSize = stream_.bufferSize * stream_.nDeviceChannels[INPUT] * formatBytes( stream_.deviceFormat[INPUT] );
+  }
+  else if ( stream_.mode == OUTPUT ) {
+    convBuffSize = ( size_t ) ( stream_.bufferSize * renderSrRatio ) * stream_.nDeviceChannels[OUTPUT] * formatBytes( stream_.deviceFormat[OUTPUT] );
+    deviceBuffSize = stream_.bufferSize * stream_.nDeviceChannels[OUTPUT] * formatBytes( stream_.deviceFormat[OUTPUT] );
+  }
+  else if ( stream_.mode == DUPLEX ) {
+    convBuffSize = std::max( ( size_t ) ( stream_.bufferSize * captureSrRatio ) * stream_.nDeviceChannels[INPUT] * formatBytes( stream_.deviceFormat[INPUT] ),
+                             ( size_t ) ( stream_.bufferSize * renderSrRatio ) * stream_.nDeviceChannels[OUTPUT] * formatBytes( stream_.deviceFormat[OUTPUT] ) );
+    deviceBuffSize = std::max( stream_.bufferSize * stream_.nDeviceChannels[INPUT] * formatBytes( stream_.deviceFormat[INPUT] ),
+                               stream_.bufferSize * stream_.nDeviceChannels[OUTPUT] * formatBytes( stream_.deviceFormat[OUTPUT] ) );
+  }
+
+  convBuffer = ( char* ) malloc( convBuffSize );
+  stream_.deviceBuffer = ( char* ) malloc( deviceBuffSize );
+  if ( !convBuffer || !stream_.deviceBuffer ) {
+    errorType = RtAudioError::MEMORY_ERROR;
+    errorText_ = "RtApiWasapi::wasapiThread: Error allocating device buffer memory.";
+    goto Exit;
+  }
+
+  // stream process loop
+  while ( stream_.state != STREAM_STOPPING ) {
+    if ( !callbackPulled ) {
+      // Callback Input
+      // ==============
+      // 1. Pull callback buffer from inputBuffer
+      // 2. If 1. was successful: Convert callback buffer to user sample rate and channel count
+      //                          Convert callback buffer to user format
+
+      if ( captureAudioClient ) {
+        // Pull callback buffer from inputBuffer
+        callbackPulled = captureBuffer.pullBuffer( convBuffer,
+                                                   ( unsigned int ) ( stream_.bufferSize * captureSrRatio ) * stream_.nDeviceChannels[INPUT],
+                                                   stream_.deviceFormat[INPUT] );
+
+        if ( callbackPulled ) {
+          // Convert callback buffer to user sample rate
+          convertBufferWasapi( stream_.deviceBuffer,
+                               convBuffer,
+                               stream_.nDeviceChannels[INPUT],
+                               captureFormat->nSamplesPerSec,
+                               stream_.sampleRate,
+                               ( unsigned int ) ( stream_.bufferSize * captureSrRatio ),
+                               convBufferSize,
+                               stream_.deviceFormat[INPUT] );
+
+          if ( stream_.doConvertBuffer[INPUT] ) {
+            // Convert callback buffer to user format
+            convertBuffer( stream_.userBuffer[INPUT],
+                           stream_.deviceBuffer,
+                           stream_.convertInfo[INPUT] );
+          }
+          else {
+            // no further conversion, simple copy deviceBuffer to userBuffer
+            memcpy( stream_.userBuffer[INPUT],
+                    stream_.deviceBuffer,
+                    stream_.bufferSize * stream_.nUserChannels[INPUT] * formatBytes( stream_.userFormat ) );
+          }
+        }
+      }
+      else {
+        // if there is no capture stream, set callbackPulled flag
+        callbackPulled = true;
+      }
+
+      // Execute Callback
+      // ================
+      // 1. Execute user callback method
+      // 2. Handle return value from callback
+
+      // if callback has not requested the stream to stop
+      if ( callbackPulled && !callbackStopped ) {
+        // Execute user callback method
+        callbackResult = callback( stream_.userBuffer[OUTPUT],
+                                   stream_.userBuffer[INPUT],
+                                   stream_.bufferSize,
+                                   getStreamTime(),
+                                   captureFlags & AUDCLNT_BUFFERFLAGS_DATA_DISCONTINUITY ? RTAUDIO_INPUT_OVERFLOW : 0,
+                                   stream_.callbackInfo.userData );
+
+        // Handle return value from callback
+        if ( callbackResult == 1 ) {
+          // instantiate a thread to stop this thread
+          HANDLE threadHandle = CreateThread( NULL, 0, stopWasapiThread, this, 0, NULL );
+          if ( !threadHandle ) {
+            errorType = RtAudioError::THREAD_ERROR;
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to instantiate stream stop thread.";
+            goto Exit;
+          }
+          else if ( !CloseHandle( threadHandle ) ) {
+            errorType = RtAudioError::THREAD_ERROR;
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to close stream stop thread handle.";
+            goto Exit;
+          }
+
+          callbackStopped = true;
+        }
+        else if ( callbackResult == 2 ) {
+          // instantiate a thread to stop this thread
+          HANDLE threadHandle = CreateThread( NULL, 0, abortWasapiThread, this, 0, NULL );
+          if ( !threadHandle ) {
+            errorType = RtAudioError::THREAD_ERROR;
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to instantiate stream abort thread.";
+            goto Exit;
+          }
+          else if ( !CloseHandle( threadHandle ) ) {
+            errorType = RtAudioError::THREAD_ERROR;
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to close stream abort thread handle.";
+            goto Exit;
+          }
+
+          callbackStopped = true;
+        }
+      }
+    }
+
+    // Callback Output
+    // ===============
+    // 1. Convert callback buffer to stream format
+    // 2. Convert callback buffer to stream sample rate and channel count
+    // 3. Push callback buffer into outputBuffer
+
+    if ( renderAudioClient && callbackPulled ) {
+      if ( stream_.doConvertBuffer[OUTPUT] ) {
+        // Convert callback buffer to stream format
+        convertBuffer( stream_.deviceBuffer,
+                       stream_.userBuffer[OUTPUT],
+                       stream_.convertInfo[OUTPUT] );
+
+      }
+
+      // Convert callback buffer to stream sample rate
+      convertBufferWasapi( convBuffer,
+                           stream_.deviceBuffer,
+                           stream_.nDeviceChannels[OUTPUT],
+                           stream_.sampleRate,
+                           renderFormat->nSamplesPerSec,
+                           stream_.bufferSize,
+                           convBufferSize,
+                           stream_.deviceFormat[OUTPUT] );
+
+      // Push callback buffer into outputBuffer
+      callbackPushed = renderBuffer.pushBuffer( convBuffer,
+                                                convBufferSize * stream_.nDeviceChannels[OUTPUT],
+                                                stream_.deviceFormat[OUTPUT] );
+    }
+    else {
+      // if there is no render stream, set callbackPushed flag
+      callbackPushed = true;
+    }
+
+    // Stream Capture
+    // ==============
+    // 1. Get capture buffer from stream
+    // 2. Push capture buffer into inputBuffer
+    // 3. If 2. was successful: Release capture buffer
+
+    if ( captureAudioClient ) {
+      // if the callback input buffer was not pulled from captureBuffer, wait for next capture event
+      if ( !callbackPulled ) {
+        WaitForSingleObject( captureEvent, INFINITE );
+      }
+
+      // Get capture buffer from stream
+      hr = captureClient->GetBuffer( &streamBuffer,
+                                     &bufferFrameCount,
+                                     &captureFlags, NULL, NULL );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve capture buffer.";
+        goto Exit;
+      }
+
+      if ( bufferFrameCount != 0 ) {
+        // Push capture buffer into inputBuffer
+        if ( captureBuffer.pushBuffer( ( char* ) streamBuffer,
+                                       bufferFrameCount * stream_.nDeviceChannels[INPUT],
+                                       stream_.deviceFormat[INPUT] ) )
+        {
+          // Release capture buffer
+          hr = captureClient->ReleaseBuffer( bufferFrameCount );
+          if ( FAILED( hr ) ) {
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to release capture buffer.";
+            goto Exit;
+          }
+        }
+        else
+        {
+          // Inform WASAPI that capture was unsuccessful
+          hr = captureClient->ReleaseBuffer( 0 );
+          if ( FAILED( hr ) ) {
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to release capture buffer.";
+            goto Exit;
+          }
+        }
+      }
+      else
+      {
+        // Inform WASAPI that capture was unsuccessful
+        hr = captureClient->ReleaseBuffer( 0 );
+        if ( FAILED( hr ) ) {
+          errorText_ = "RtApiWasapi::wasapiThread: Unable to release capture buffer.";
+          goto Exit;
+        }
+      }
+    }
+
+    // Stream Render
+    // =============
+    // 1. Get render buffer from stream
+    // 2. Pull next buffer from outputBuffer
+    // 3. If 2. was successful: Fill render buffer with next buffer
+    //                          Release render buffer
+
+    if ( renderAudioClient ) {
+      // if the callback output buffer was not pushed to renderBuffer, wait for next render event
+      if ( callbackPulled && !callbackPushed ) {
+        WaitForSingleObject( renderEvent, INFINITE );
+      }
+
+      // Get render buffer from stream
+      hr = renderAudioClient->GetBufferSize( &bufferFrameCount );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve render buffer size.";
+        goto Exit;
+      }
+
+      hr = renderAudioClient->GetCurrentPadding( &numFramesPadding );
+      if ( FAILED( hr ) ) {
+        errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve render buffer padding.";
+        goto Exit;
+      }
+
+      bufferFrameCount -= numFramesPadding;
+
+      if ( bufferFrameCount != 0 ) {
+        hr = renderClient->GetBuffer( bufferFrameCount, &streamBuffer );
+        if ( FAILED( hr ) ) {
+          errorText_ = "RtApiWasapi::wasapiThread: Unable to retrieve render buffer.";
+          goto Exit;
+        }
+
+        // Pull next buffer from outputBuffer
+        // Fill render buffer with next buffer
+        if ( renderBuffer.pullBuffer( ( char* ) streamBuffer,
+                                      bufferFrameCount * stream_.nDeviceChannels[OUTPUT],
+                                      stream_.deviceFormat[OUTPUT] ) )
+        {
+          // Release render buffer
+          hr = renderClient->ReleaseBuffer( bufferFrameCount, 0 );
+          if ( FAILED( hr ) ) {
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to release render buffer.";
+            goto Exit;
+          }
+        }
+        else
+        {
+          // Inform WASAPI that render was unsuccessful
+          hr = renderClient->ReleaseBuffer( 0, 0 );
+          if ( FAILED( hr ) ) {
+            errorText_ = "RtApiWasapi::wasapiThread: Unable to release render buffer.";
+            goto Exit;
+          }
+        }
+      }
+      else
+      {
+        // Inform WASAPI that render was unsuccessful
+        hr = renderClient->ReleaseBuffer( 0, 0 );
+        if ( FAILED( hr ) ) {
+          errorText_ = "RtApiWasapi::wasapiThread: Unable to release render buffer.";
+          goto Exit;
+        }
+      }
+    }
+
+    // if the callback buffer was pushed renderBuffer reset callbackPulled flag
+    if ( callbackPushed ) {
+      callbackPulled = false;
+      // tick stream time
+      RtApi::tickStreamTime();
+    }
+
+  }
+
+Exit:
+  // clean up
+  CoTaskMemFree( captureFormat );
+  CoTaskMemFree( renderFormat );
+
+  free ( convBuffer );
+
+  CoUninitialize();
+
+  // update stream state
+  stream_.state = STREAM_STOPPED;
+
+  if ( errorText_.empty() )
+    return;
+  else
+    error( errorType );
+}
+
+//******************** End of __WINDOWS_WASAPI__ *********************//
+#endif
+
+
+#if defined(__WINDOWS_DS__) // Windows DirectSound API
+
+// Modified by Robin Davies, October 2005
+// - Improvements to DirectX pointer chasing. 
+// - Bug fix for non-power-of-two Asio granularity used by Edirol PCR-A30.
+// - Auto-call CoInitialize for DSOUND and ASIO platforms.
+// Various revisions for RtAudio 4.0 by Gary Scavone, April 2007
+// Changed device query structure for RtAudio 4.0.7, January 2010
+
+#include <dsound.h>
+#include <assert.h>
+#include <algorithm>
+
+#if defined(__MINGW32__)
+  // missing from latest mingw winapi
+#define WAVE_FORMAT_96M08 0x00010000 /* 96 kHz, Mono, 8-bit */
+#define WAVE_FORMAT_96S08 0x00020000 /* 96 kHz, Stereo, 8-bit */
+#define WAVE_FORMAT_96M16 0x00040000 /* 96 kHz, Mono, 16-bit */
+#define WAVE_FORMAT_96S16 0x00080000 /* 96 kHz, Stereo, 16-bit */
+#endif
+
+#define MINIMUM_DEVICE_BUFFER_SIZE 32768
+
+#ifdef _MSC_VER // if Microsoft Visual C++
+#pragma comment( lib, "winmm.lib" ) // then, auto-link winmm.lib. Otherwise, it has to be added manually.
+#endif
+
+static inline DWORD dsPointerBetween( DWORD pointer, DWORD laterPointer, DWORD earlierPointer, DWORD bufferSize )
+{
+  if ( pointer > bufferSize ) pointer -= bufferSize;
+  if ( laterPointer < earlierPointer ) laterPointer += bufferSize;
+  if ( pointer < earlierPointer ) pointer += bufferSize;
+  return pointer >= earlierPointer && pointer < laterPointer;
+}
+
+// A structure to hold various information related to the DirectSound
+// API implementation.
+struct DsHandle {
+  unsigned int drainCounter; // Tracks callback counts when draining
+  bool internalDrain;        // Indicates if stop is initiated from callback or not.
+  void *id[2];
+  void *buffer[2];
+  bool xrun[2];
+  UINT bufferPointer[2];  
+  DWORD dsBufferSize[2];
+  DWORD dsPointerLeadTime[2]; // the number of bytes ahead of the safe pointer to lead by.
+  HANDLE condition;
+
+  DsHandle()
+    :drainCounter(0), internalDrain(false) { id[0] = 0; id[1] = 0; buffer[0] = 0; buffer[1] = 0; xrun[0] = false; xrun[1] = false; bufferPointer[0] = 0; bufferPointer[1] = 0; }
+};
+
+// Declarations for utility functions, callbacks, and structures
+// specific to the DirectSound implementation.
+static BOOL CALLBACK deviceQueryCallback( LPGUID lpguid,
+                                          LPCTSTR description,
+                                          LPCTSTR module,
+                                          LPVOID lpContext );
+
+static const char* getErrorString( int code );
+
+static unsigned __stdcall callbackHandler( void *ptr );
+
+struct DsDevice {
+  LPGUID id[2];
+  bool validId[2];
+  bool found;
+  std::string name;
+
+  DsDevice()
+  : found(false) { validId[0] = false; validId[1] = false; }
+};
+
+struct DsProbeData {
+  bool isInput;
+  std::vector<struct DsDevice>* dsDevices;
+};
+
+RtApiDs :: RtApiDs()
+{
+  // Dsound will run both-threaded. If CoInitialize fails, then just
+  // accept whatever the mainline chose for a threading model.
+  coInitialized_ = false;
+  HRESULT hr = CoInitialize( NULL );
+  if ( !FAILED( hr ) ) coInitialized_ = true;
+}
+
+RtApiDs :: ~RtApiDs()
+{
+  if ( coInitialized_ ) CoUninitialize(); // balanced call.
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+}
+
+// The DirectSound default output is always the first device.
+unsigned int RtApiDs :: getDefaultOutputDevice( void )
+{
+  return 0;
+}
+
+// The DirectSound default input is always the first input device,
+// which is the first capture device enumerated.
+unsigned int RtApiDs :: getDefaultInputDevice( void )
+{
+  return 0;
+}
+
+unsigned int RtApiDs :: getDeviceCount( void )
+{
+  // Set query flag for previously found devices to false, so that we
+  // can check for any devices that have disappeared.
+  for ( unsigned int i=0; i<dsDevices.size(); i++ )
+    dsDevices[i].found = false;
+
+  // Query DirectSound devices.
+  struct DsProbeData probeInfo;
+  probeInfo.isInput = false;
+  probeInfo.dsDevices = &dsDevices;
+  HRESULT result = DirectSoundEnumerate( (LPDSENUMCALLBACK) deviceQueryCallback, &probeInfo );
+  if ( FAILED( result ) ) {
+    errorStream_ << "RtApiDs::getDeviceCount: error (" << getErrorString( result ) << ") enumerating output devices!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+  }
+
+  // Query DirectSoundCapture devices.
+  probeInfo.isInput = true;
+  result = DirectSoundCaptureEnumerate( (LPDSENUMCALLBACK) deviceQueryCallback, &probeInfo );
+  if ( FAILED( result ) ) {
+    errorStream_ << "RtApiDs::getDeviceCount: error (" << getErrorString( result ) << ") enumerating input devices!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+  }
+
+  // Clean out any devices that may have disappeared (code update submitted by Eli Zehngut).
+  for ( unsigned int i=0; i<dsDevices.size(); ) {
+    if ( dsDevices[i].found == false ) dsDevices.erase( dsDevices.begin() + i );
+    else i++;
+  }
+
+  return static_cast<unsigned int>(dsDevices.size());
+}
+
+RtAudio::DeviceInfo RtApiDs :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  if ( dsDevices.size() == 0 ) {
+    // Force a query of all devices
+    getDeviceCount();
+    if ( dsDevices.size() == 0 ) {
+      errorText_ = "RtApiDs::getDeviceInfo: no devices found!";
+      error( RtAudioError::INVALID_USE );
+      return info;
+    }
+  }
+
+  if ( device >= dsDevices.size() ) {
+    errorText_ = "RtApiDs::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  HRESULT result;
+  if ( dsDevices[ device ].validId[0] == false ) goto probeInput;
+
+  LPDIRECTSOUND output;
+  DSCAPS outCaps;
+  result = DirectSoundCreate( dsDevices[ device ].id[0], &output, NULL );
+  if ( FAILED( result ) ) {
+    errorStream_ << "RtApiDs::getDeviceInfo: error (" << getErrorString( result ) << ") opening output device (" << dsDevices[ device ].name << ")!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    goto probeInput;
+  }
+
+  outCaps.dwSize = sizeof( outCaps );
+  result = output->GetCaps( &outCaps );
+  if ( FAILED( result ) ) {
+    output->Release();
+    errorStream_ << "RtApiDs::getDeviceInfo: error (" << getErrorString( result ) << ") getting capabilities!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    goto probeInput;
+  }
+
+  // Get output channel information.
+  info.outputChannels = ( outCaps.dwFlags & DSCAPS_PRIMARYSTEREO ) ? 2 : 1;
+
+  // Get sample rate information.
+  info.sampleRates.clear();
+  for ( unsigned int k=0; k<MAX_SAMPLE_RATES; k++ ) {
+    if ( SAMPLE_RATES[k] >= (unsigned int) outCaps.dwMinSecondarySampleRate &&
+         SAMPLE_RATES[k] <= (unsigned int) outCaps.dwMaxSecondarySampleRate ) {
+      info.sampleRates.push_back( SAMPLE_RATES[k] );
+
+      if ( !info.preferredSampleRate || ( SAMPLE_RATES[k] <= 48000 && SAMPLE_RATES[k] > info.preferredSampleRate ) )
+        info.preferredSampleRate = SAMPLE_RATES[k];
+    }
+  }
+
+  // Get format information.
+  if ( outCaps.dwFlags & DSCAPS_PRIMARY16BIT ) info.nativeFormats |= RTAUDIO_SINT16;
+  if ( outCaps.dwFlags & DSCAPS_PRIMARY8BIT ) info.nativeFormats |= RTAUDIO_SINT8;
+
+  output->Release();
+
+  if ( getDefaultOutputDevice() == device )
+    info.isDefaultOutput = true;
+
+  if ( dsDevices[ device ].validId[1] == false ) {
+    info.name = dsDevices[ device ].name;
+    info.probed = true;
+    return info;
+  }
+
+ probeInput:
+
+  LPDIRECTSOUNDCAPTURE input;
+  result = DirectSoundCaptureCreate( dsDevices[ device ].id[1], &input, NULL );
+  if ( FAILED( result ) ) {
+    errorStream_ << "RtApiDs::getDeviceInfo: error (" << getErrorString( result ) << ") opening input device (" << dsDevices[ device ].name << ")!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  DSCCAPS inCaps;
+  inCaps.dwSize = sizeof( inCaps );
+  result = input->GetCaps( &inCaps );
+  if ( FAILED( result ) ) {
+    input->Release();
+    errorStream_ << "RtApiDs::getDeviceInfo: error (" << getErrorString( result ) << ") getting object capabilities (" << dsDevices[ device ].name << ")!";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Get input channel information.
+  info.inputChannels = inCaps.dwChannels;
+
+  // Get sample rate and format information.
+  std::vector<unsigned int> rates;
+  if ( inCaps.dwChannels >= 2 ) {
+    if ( inCaps.dwFormats & WAVE_FORMAT_1S16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_2S16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_4S16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_96S16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_1S08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_2S08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_4S08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_96S08 ) info.nativeFormats |= RTAUDIO_SINT8;
+
+    if ( info.nativeFormats & RTAUDIO_SINT16 ) {
+      if ( inCaps.dwFormats & WAVE_FORMAT_1S16 ) rates.push_back( 11025 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_2S16 ) rates.push_back( 22050 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_4S16 ) rates.push_back( 44100 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_96S16 ) rates.push_back( 96000 );
+    }
+    else if ( info.nativeFormats & RTAUDIO_SINT8 ) {
+      if ( inCaps.dwFormats & WAVE_FORMAT_1S08 ) rates.push_back( 11025 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_2S08 ) rates.push_back( 22050 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_4S08 ) rates.push_back( 44100 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_96S08 ) rates.push_back( 96000 );
+    }
+  }
+  else if ( inCaps.dwChannels == 1 ) {
+    if ( inCaps.dwFormats & WAVE_FORMAT_1M16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_2M16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_4M16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_96M16 ) info.nativeFormats |= RTAUDIO_SINT16;
+    if ( inCaps.dwFormats & WAVE_FORMAT_1M08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_2M08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_4M08 ) info.nativeFormats |= RTAUDIO_SINT8;
+    if ( inCaps.dwFormats & WAVE_FORMAT_96M08 ) info.nativeFormats |= RTAUDIO_SINT8;
+
+    if ( info.nativeFormats & RTAUDIO_SINT16 ) {
+      if ( inCaps.dwFormats & WAVE_FORMAT_1M16 ) rates.push_back( 11025 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_2M16 ) rates.push_back( 22050 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_4M16 ) rates.push_back( 44100 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_96M16 ) rates.push_back( 96000 );
+    }
+    else if ( info.nativeFormats & RTAUDIO_SINT8 ) {
+      if ( inCaps.dwFormats & WAVE_FORMAT_1M08 ) rates.push_back( 11025 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_2M08 ) rates.push_back( 22050 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_4M08 ) rates.push_back( 44100 );
+      if ( inCaps.dwFormats & WAVE_FORMAT_96M08 ) rates.push_back( 96000 );
+    }
+  }
+  else info.inputChannels = 0; // technically, this would be an error
+
+  input->Release();
+
+  if ( info.inputChannels == 0 ) return info;
+
+  // Copy the supported rates to the info structure but avoid duplication.
+  bool found;
+  for ( unsigned int i=0; i<rates.size(); i++ ) {
+    found = false;
+    for ( unsigned int j=0; j<info.sampleRates.size(); j++ ) {
+      if ( rates[i] == info.sampleRates[j] ) {
+        found = true;
+        break;
+      }
+    }
+    if ( found == false ) info.sampleRates.push_back( rates[i] );
+  }
+  std::sort( info.sampleRates.begin(), info.sampleRates.end() );
+
+  // If device opens for both playback and capture, we determine the channels.
+  if ( info.outputChannels > 0 && info.inputChannels > 0 )
+    info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+
+  if ( device == 0 ) info.isDefaultInput = true;
+
+  // Copy name and return.
+  info.name = dsDevices[ device ].name;
+  info.probed = true;
+  return info;
+}
+
+bool RtApiDs :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                 unsigned int firstChannel, unsigned int sampleRate,
+                                 RtAudioFormat format, unsigned int *bufferSize,
+                                 RtAudio::StreamOptions *options )
+{
+  if ( channels + firstChannel > 2 ) {
+    errorText_ = "RtApiDs::probeDeviceOpen: DirectSound does not support more than 2 channels per device.";
+    return FAILURE;
+  }
+
+  size_t nDevices = dsDevices.size();
+  if ( nDevices == 0 ) {
+    // This should not happen because a check is made before this function is called.
+    errorText_ = "RtApiDs::probeDeviceOpen: no devices found!";
+    return FAILURE;
+  }
+
+  if ( device >= nDevices ) {
+    // This should not happen because a check is made before this function is called.
+    errorText_ = "RtApiDs::probeDeviceOpen: device ID is invalid!";
+    return FAILURE;
+  }
+
+  if ( mode == OUTPUT ) {
+    if ( dsDevices[ device ].validId[0] == false ) {
+      errorStream_ << "RtApiDs::probeDeviceOpen: device (" << device << ") does not support output!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+  else { // mode == INPUT
+    if ( dsDevices[ device ].validId[1] == false ) {
+      errorStream_ << "RtApiDs::probeDeviceOpen: device (" << device << ") does not support input!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+
+  // According to a note in PortAudio, using GetDesktopWindow()
+  // instead of GetForegroundWindow() is supposed to avoid problems
+  // that occur when the application's window is not the foreground
+  // window.  Also, if the application window closes before the
+  // DirectSound buffer, DirectSound can crash.  In the past, I had
+  // problems when using GetDesktopWindow() but it seems fine now
+  // (January 2010).  I'll leave it commented here.
+  // HWND hWnd = GetForegroundWindow();
+  HWND hWnd = GetDesktopWindow();
+
+  // Check the numberOfBuffers parameter and limit the lowest value to
+  // two.  This is a judgement call and a value of two is probably too
+  // low for capture, but it should work for playback.
+  int nBuffers = 0;
+  if ( options ) nBuffers = options->numberOfBuffers;
+  if ( options && options->flags & RTAUDIO_MINIMIZE_LATENCY ) nBuffers = 2;
+  if ( nBuffers < 2 ) nBuffers = 3;
+
+  // Check the lower range of the user-specified buffer size and set
+  // (arbitrarily) to a lower bound of 32.
+  if ( *bufferSize < 32 ) *bufferSize = 32;
+
+  // Create the wave format structure.  The data format setting will
+  // be determined later.
+  WAVEFORMATEX waveFormat;
+  ZeroMemory( &waveFormat, sizeof(WAVEFORMATEX) );
+  waveFormat.wFormatTag = WAVE_FORMAT_PCM;
+  waveFormat.nChannels = channels + firstChannel;
+  waveFormat.nSamplesPerSec = (unsigned long) sampleRate;
+
+  // Determine the device buffer size. By default, we'll use the value
+  // defined above (32K), but we will grow it to make allowances for
+  // very large software buffer sizes.
+  DWORD dsBufferSize = MINIMUM_DEVICE_BUFFER_SIZE;
+  DWORD dsPointerLeadTime = 0;
+
+  void *ohandle = 0, *bhandle = 0;
+  HRESULT result;
+  if ( mode == OUTPUT ) {
+
+    LPDIRECTSOUND output;
+    result = DirectSoundCreate( dsDevices[ device ].id[0], &output, NULL );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") opening output device (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    DSCAPS outCaps;
+    outCaps.dwSize = sizeof( outCaps );
+    result = output->GetCaps( &outCaps );
+    if ( FAILED( result ) ) {
+      output->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") getting capabilities (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Check channel information.
+    if ( channels + firstChannel == 2 && !( outCaps.dwFlags & DSCAPS_PRIMARYSTEREO ) ) {
+      errorStream_ << "RtApiDs::getDeviceInfo: the output device (" << dsDevices[ device ].name << ") does not support stereo playback.";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Check format information.  Use 16-bit format unless not
+    // supported or user requests 8-bit.
+    if ( outCaps.dwFlags & DSCAPS_PRIMARY16BIT &&
+         !( format == RTAUDIO_SINT8 && outCaps.dwFlags & DSCAPS_PRIMARY8BIT ) ) {
+      waveFormat.wBitsPerSample = 16;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+    }
+    else {
+      waveFormat.wBitsPerSample = 8;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+    }
+    stream_.userFormat = format;
+
+    // Update wave format structure and buffer information.
+    waveFormat.nBlockAlign = waveFormat.nChannels * waveFormat.wBitsPerSample / 8;
+    waveFormat.nAvgBytesPerSec = waveFormat.nSamplesPerSec * waveFormat.nBlockAlign;
+    dsPointerLeadTime = nBuffers * (*bufferSize) * (waveFormat.wBitsPerSample / 8) * channels;
+
+    // If the user wants an even bigger buffer, increase the device buffer size accordingly.
+    while ( dsPointerLeadTime * 2U > dsBufferSize )
+      dsBufferSize *= 2;
+
+    // Set cooperative level to DSSCL_EXCLUSIVE ... sound stops when window focus changes.
+    // result = output->SetCooperativeLevel( hWnd, DSSCL_EXCLUSIVE );
+    // Set cooperative level to DSSCL_PRIORITY ... sound remains when window focus changes.
+    result = output->SetCooperativeLevel( hWnd, DSSCL_PRIORITY );
+    if ( FAILED( result ) ) {
+      output->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") setting cooperative level (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Even though we will write to the secondary buffer, we need to
+    // access the primary buffer to set the correct output format
+    // (since the default is 8-bit, 22 kHz!).  Setup the DS primary
+    // buffer description.
+    DSBUFFERDESC bufferDescription;
+    ZeroMemory( &bufferDescription, sizeof( DSBUFFERDESC ) );
+    bufferDescription.dwSize = sizeof( DSBUFFERDESC );
+    bufferDescription.dwFlags = DSBCAPS_PRIMARYBUFFER;
+
+    // Obtain the primary buffer
+    LPDIRECTSOUNDBUFFER buffer;
+    result = output->CreateSoundBuffer( &bufferDescription, &buffer, NULL );
+    if ( FAILED( result ) ) {
+      output->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") accessing primary buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Set the primary DS buffer sound format.
+    result = buffer->SetFormat( &waveFormat );
+    if ( FAILED( result ) ) {
+      output->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") setting primary buffer format (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Setup the secondary DS buffer description.
+    ZeroMemory( &bufferDescription, sizeof( DSBUFFERDESC ) );
+    bufferDescription.dwSize = sizeof( DSBUFFERDESC );
+    bufferDescription.dwFlags = ( DSBCAPS_STICKYFOCUS |
+                                  DSBCAPS_GLOBALFOCUS |
+                                  DSBCAPS_GETCURRENTPOSITION2 |
+                                  DSBCAPS_LOCHARDWARE );  // Force hardware mixing
+    bufferDescription.dwBufferBytes = dsBufferSize;
+    bufferDescription.lpwfxFormat = &waveFormat;
+
+    // Try to create the secondary DS buffer.  If that doesn't work,
+    // try to use software mixing.  Otherwise, there's a problem.
+    result = output->CreateSoundBuffer( &bufferDescription, &buffer, NULL );
+    if ( FAILED( result ) ) {
+      bufferDescription.dwFlags = ( DSBCAPS_STICKYFOCUS |
+                                    DSBCAPS_GLOBALFOCUS |
+                                    DSBCAPS_GETCURRENTPOSITION2 |
+                                    DSBCAPS_LOCSOFTWARE );  // Force software mixing
+      result = output->CreateSoundBuffer( &bufferDescription, &buffer, NULL );
+      if ( FAILED( result ) ) {
+        output->Release();
+        errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") creating secondary buffer (" << dsDevices[ device ].name << ")!";
+        errorText_ = errorStream_.str();
+        return FAILURE;
+      }
+    }
+
+    // Get the buffer size ... might be different from what we specified.
+    DSBCAPS dsbcaps;
+    dsbcaps.dwSize = sizeof( DSBCAPS );
+    result = buffer->GetCaps( &dsbcaps );
+    if ( FAILED( result ) ) {
+      output->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") getting buffer settings (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    dsBufferSize = dsbcaps.dwBufferBytes;
+
+    // Lock the DS buffer
+    LPVOID audioPtr;
+    DWORD dataLen;
+    result = buffer->Lock( 0, dsBufferSize, &audioPtr, &dataLen, NULL, NULL, 0 );
+    if ( FAILED( result ) ) {
+      output->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") locking buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Zero the DS buffer
+    ZeroMemory( audioPtr, dataLen );
+
+    // Unlock the DS buffer
+    result = buffer->Unlock( audioPtr, dataLen, NULL, 0 );
+    if ( FAILED( result ) ) {
+      output->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") unlocking buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    ohandle = (void *) output;
+    bhandle = (void *) buffer;
+  }
+
+  if ( mode == INPUT ) {
+
+    LPDIRECTSOUNDCAPTURE input;
+    result = DirectSoundCaptureCreate( dsDevices[ device ].id[1], &input, NULL );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") opening input device (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    DSCCAPS inCaps;
+    inCaps.dwSize = sizeof( inCaps );
+    result = input->GetCaps( &inCaps );
+    if ( FAILED( result ) ) {
+      input->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") getting input capabilities (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Check channel information.
+    if ( inCaps.dwChannels < channels + firstChannel ) {
+      errorText_ = "RtApiDs::getDeviceInfo: the input device does not support requested input channels.";
+      return FAILURE;
+    }
+
+    // Check format information.  Use 16-bit format unless user
+    // requests 8-bit.
+    DWORD deviceFormats;
+    if ( channels + firstChannel == 2 ) {
+      deviceFormats = WAVE_FORMAT_1S08 | WAVE_FORMAT_2S08 | WAVE_FORMAT_4S08 | WAVE_FORMAT_96S08;
+      if ( format == RTAUDIO_SINT8 && inCaps.dwFormats & deviceFormats ) {
+        waveFormat.wBitsPerSample = 8;
+        stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+      }
+      else { // assume 16-bit is supported
+        waveFormat.wBitsPerSample = 16;
+        stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+      }
+    }
+    else { // channel == 1
+      deviceFormats = WAVE_FORMAT_1M08 | WAVE_FORMAT_2M08 | WAVE_FORMAT_4M08 | WAVE_FORMAT_96M08;
+      if ( format == RTAUDIO_SINT8 && inCaps.dwFormats & deviceFormats ) {
+        waveFormat.wBitsPerSample = 8;
+        stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+      }
+      else { // assume 16-bit is supported
+        waveFormat.wBitsPerSample = 16;
+        stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+      }
+    }
+    stream_.userFormat = format;
+
+    // Update wave format structure and buffer information.
+    waveFormat.nBlockAlign = waveFormat.nChannels * waveFormat.wBitsPerSample / 8;
+    waveFormat.nAvgBytesPerSec = waveFormat.nSamplesPerSec * waveFormat.nBlockAlign;
+    dsPointerLeadTime = nBuffers * (*bufferSize) * (waveFormat.wBitsPerSample / 8) * channels;
+
+    // If the user wants an even bigger buffer, increase the device buffer size accordingly.
+    while ( dsPointerLeadTime * 2U > dsBufferSize )
+      dsBufferSize *= 2;
+
+    // Setup the secondary DS buffer description.
+    DSCBUFFERDESC bufferDescription;
+    ZeroMemory( &bufferDescription, sizeof( DSCBUFFERDESC ) );
+    bufferDescription.dwSize = sizeof( DSCBUFFERDESC );
+    bufferDescription.dwFlags = 0;
+    bufferDescription.dwReserved = 0;
+    bufferDescription.dwBufferBytes = dsBufferSize;
+    bufferDescription.lpwfxFormat = &waveFormat;
+
+    // Create the capture buffer.
+    LPDIRECTSOUNDCAPTUREBUFFER buffer;
+    result = input->CreateCaptureBuffer( &bufferDescription, &buffer, NULL );
+    if ( FAILED( result ) ) {
+      input->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") creating input buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Get the buffer size ... might be different from what we specified.
+    DSCBCAPS dscbcaps;
+    dscbcaps.dwSize = sizeof( DSCBCAPS );
+    result = buffer->GetCaps( &dscbcaps );
+    if ( FAILED( result ) ) {
+      input->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") getting buffer settings (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    dsBufferSize = dscbcaps.dwBufferBytes;
+
+    // NOTE: We could have a problem here if this is a duplex stream
+    // and the play and capture hardware buffer sizes are different
+    // (I'm actually not sure if that is a problem or not).
+    // Currently, we are not verifying that.
+
+    // Lock the capture buffer
+    LPVOID audioPtr;
+    DWORD dataLen;
+    result = buffer->Lock( 0, dsBufferSize, &audioPtr, &dataLen, NULL, NULL, 0 );
+    if ( FAILED( result ) ) {
+      input->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") locking input buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    // Zero the buffer
+    ZeroMemory( audioPtr, dataLen );
+
+    // Unlock the buffer
+    result = buffer->Unlock( audioPtr, dataLen, NULL, 0 );
+    if ( FAILED( result ) ) {
+      input->Release();
+      buffer->Release();
+      errorStream_ << "RtApiDs::probeDeviceOpen: error (" << getErrorString( result ) << ") unlocking input buffer (" << dsDevices[ device ].name << ")!";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+
+    ohandle = (void *) input;
+    bhandle = (void *) buffer;
+  }
+
+  // Set various stream parameters
+  DsHandle *handle = 0;
+  stream_.nDeviceChannels[mode] = channels + firstChannel;
+  stream_.nUserChannels[mode] = channels;
+  stream_.bufferSize = *bufferSize;
+  stream_.channelOffset[mode] = firstChannel;
+  stream_.deviceInterleaved[mode] = true;
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) stream_.userInterleaved = false;
+  else stream_.userInterleaved = true;
+
+  // Set flag for buffer conversion
+  stream_.doConvertBuffer[mode] = false;
+  if (stream_.nUserChannels[mode] != stream_.nDeviceChannels[mode])
+    stream_.doConvertBuffer[mode] = true;
+  if (stream_.userFormat != stream_.deviceFormat[mode])
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+       stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate necessary internal buffers
+  long bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiDs::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( mode == INPUT ) {
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+        if ( bufferBytes <= (long) bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiDs::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  // Allocate our DsHandle structures for the stream.
+  if ( stream_.apiHandle == 0 ) {
+    try {
+      handle = new DsHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiDs::probeDeviceOpen: error allocating AsioHandle memory.";
+      goto error;
+    }
+
+    // Create a manual-reset event.
+    handle->condition = CreateEvent( NULL,   // no security
+                                     TRUE,   // manual-reset
+                                     FALSE,  // non-signaled initially
+                                     NULL ); // unnamed
+    stream_.apiHandle = (void *) handle;
+  }
+  else
+    handle = (DsHandle *) stream_.apiHandle;
+  handle->id[mode] = ohandle;
+  handle->buffer[mode] = bhandle;
+  handle->dsBufferSize[mode] = dsBufferSize;
+  handle->dsPointerLeadTime[mode] = dsPointerLeadTime;
+
+  stream_.device[mode] = device;
+  stream_.state = STREAM_STOPPED;
+  if ( stream_.mode == OUTPUT && mode == INPUT )
+    // We had already set up an output stream.
+    stream_.mode = DUPLEX;
+  else
+    stream_.mode = mode;
+  stream_.nBuffers = nBuffers;
+  stream_.sampleRate = sampleRate;
+
+  // Setup the buffer conversion information structure.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, firstChannel );
+
+  // Setup the callback thread.
+  if ( stream_.callbackInfo.isRunning == false ) {
+    unsigned threadId;
+    stream_.callbackInfo.isRunning = true;
+    stream_.callbackInfo.object = (void *) this;
+    stream_.callbackInfo.thread = _beginthreadex( NULL, 0, &callbackHandler,
+                                                  &stream_.callbackInfo, 0, &threadId );
+    if ( stream_.callbackInfo.thread == 0 ) {
+      errorText_ = "RtApiDs::probeDeviceOpen: error creating callback thread!";
+      goto error;
+    }
+
+    // Boost DS thread priority
+    SetThreadPriority( (HANDLE) stream_.callbackInfo.thread, THREAD_PRIORITY_HIGHEST );
+  }
+  return SUCCESS;
+
+ error:
+  if ( handle ) {
+    if ( handle->buffer[0] ) { // the object pointer can be NULL and valid
+      LPDIRECTSOUND object = (LPDIRECTSOUND) handle->id[0];
+      LPDIRECTSOUNDBUFFER buffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+      if ( buffer ) buffer->Release();
+      object->Release();
+    }
+    if ( handle->buffer[1] ) {
+      LPDIRECTSOUNDCAPTURE object = (LPDIRECTSOUNDCAPTURE) handle->id[1];
+      LPDIRECTSOUNDCAPTUREBUFFER buffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+      if ( buffer ) buffer->Release();
+      object->Release();
+    }
+    CloseHandle( handle->condition );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.state = STREAM_CLOSED;
+  return FAILURE;
+}
+
+void RtApiDs :: closeStream()
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiDs::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // Stop the callback thread.
+  stream_.callbackInfo.isRunning = false;
+  WaitForSingleObject( (HANDLE) stream_.callbackInfo.thread, INFINITE );
+  CloseHandle( (HANDLE) stream_.callbackInfo.thread );
+
+  DsHandle *handle = (DsHandle *) stream_.apiHandle;
+  if ( handle ) {
+    if ( handle->buffer[0] ) { // the object pointer can be NULL and valid
+      LPDIRECTSOUND object = (LPDIRECTSOUND) handle->id[0];
+      LPDIRECTSOUNDBUFFER buffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+      if ( buffer ) {
+        buffer->Stop();
+        buffer->Release();
+      }
+      object->Release();
+    }
+    if ( handle->buffer[1] ) {
+      LPDIRECTSOUNDCAPTURE object = (LPDIRECTSOUNDCAPTURE) handle->id[1];
+      LPDIRECTSOUNDCAPTUREBUFFER buffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+      if ( buffer ) {
+        buffer->Stop();
+        buffer->Release();
+      }
+      object->Release();
+    }
+    CloseHandle( handle->condition );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+void RtApiDs :: startStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiDs::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  DsHandle *handle = (DsHandle *) stream_.apiHandle;
+
+  // Increase scheduler frequency on lesser windows (a side-effect of
+  // increasing timer accuracy).  On greater windows (Win2K or later),
+  // this is already in effect.
+  timeBeginPeriod( 1 ); 
+
+  buffersRolling = false;
+  duplexPrerollBytes = 0;
+
+  if ( stream_.mode == DUPLEX ) {
+    // 0.5 seconds of silence in DUPLEX mode while the devices spin up and synchronize.
+    duplexPrerollBytes = (int) ( 0.5 * stream_.sampleRate * formatBytes( stream_.deviceFormat[1] ) * stream_.nDeviceChannels[1] );
+  }
+
+  HRESULT result = 0;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    LPDIRECTSOUNDBUFFER buffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+    result = buffer->Play( 0, 0, DSBPLAY_LOOPING );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::startStream: error (" << getErrorString( result ) << ") starting output buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    LPDIRECTSOUNDCAPTUREBUFFER buffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+    result = buffer->Start( DSCBSTART_LOOPING );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::startStream: error (" << getErrorString( result ) << ") starting input buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  handle->drainCounter = 0;
+  handle->internalDrain = false;
+  ResetEvent( handle->condition );
+  stream_.state = STREAM_RUNNING;
+
+ unlock:
+  if ( FAILED( result ) ) error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiDs :: stopStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiDs::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  HRESULT result = 0;
+  LPVOID audioPtr;
+  DWORD dataLen;
+  DsHandle *handle = (DsHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    if ( handle->drainCounter == 0 ) {
+      handle->drainCounter = 2;
+      WaitForSingleObject( handle->condition, INFINITE );  // block until signaled
+    }
+
+    stream_.state = STREAM_STOPPED;
+
+    MUTEX_LOCK( &stream_.mutex );
+
+    // Stop the buffer and clear memory
+    LPDIRECTSOUNDBUFFER buffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+    result = buffer->Stop();
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") stopping output buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // Lock the buffer and clear it so that if we start to play again,
+    // we won't have old data playing.
+    result = buffer->Lock( 0, handle->dsBufferSize[0], &audioPtr, &dataLen, NULL, NULL, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") locking output buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // Zero the DS buffer
+    ZeroMemory( audioPtr, dataLen );
+
+    // Unlock the DS buffer
+    result = buffer->Unlock( audioPtr, dataLen, NULL, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") unlocking output buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // If we start playing again, we must begin at beginning of buffer.
+    handle->bufferPointer[0] = 0;
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+    LPDIRECTSOUNDCAPTUREBUFFER buffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+    audioPtr = NULL;
+    dataLen = 0;
+
+    stream_.state = STREAM_STOPPED;
+
+    if ( stream_.mode != DUPLEX )
+      MUTEX_LOCK( &stream_.mutex );
+
+    result = buffer->Stop();
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") stopping input buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // Lock the buffer and clear it so that if we start to play again,
+    // we won't have old data playing.
+    result = buffer->Lock( 0, handle->dsBufferSize[1], &audioPtr, &dataLen, NULL, NULL, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") locking input buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // Zero the DS buffer
+    ZeroMemory( audioPtr, dataLen );
+
+    // Unlock the DS buffer
+    result = buffer->Unlock( audioPtr, dataLen, NULL, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::stopStream: error (" << getErrorString( result ) << ") unlocking input buffer!";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+
+    // If we start recording again, we must begin at beginning of buffer.
+    handle->bufferPointer[1] = 0;
+  }
+
+ unlock:
+  timeEndPeriod( 1 ); // revert to normal scheduler frequency on lesser windows.
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( FAILED( result ) ) error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiDs :: abortStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiDs::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  DsHandle *handle = (DsHandle *) stream_.apiHandle;
+  handle->drainCounter = 2;
+
+  stopStream();
+}
+
+void RtApiDs :: callbackEvent()
+{
+  if ( stream_.state == STREAM_STOPPED || stream_.state == STREAM_STOPPING ) {
+    Sleep( 50 ); // sleep 50 milliseconds
+    return;
+  }
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiDs::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  CallbackInfo *info = (CallbackInfo *) &stream_.callbackInfo;
+  DsHandle *handle = (DsHandle *) stream_.apiHandle;
+
+  // Check if we were draining the stream and signal is finished.
+  if ( handle->drainCounter > stream_.nBuffers + 2 ) {
+
+    stream_.state = STREAM_STOPPING;
+    if ( handle->internalDrain == false )
+      SetEvent( handle->condition );
+    else
+      stopStream();
+    return;
+  }
+
+  // Invoke user callback to get fresh output data UNLESS we are
+  // draining stream.
+  if ( handle->drainCounter == 0 ) {
+    RtAudioCallback callback = (RtAudioCallback) info->callback;
+    double streamTime = getStreamTime();
+    RtAudioStreamStatus status = 0;
+    if ( stream_.mode != INPUT && handle->xrun[0] == true ) {
+      status |= RTAUDIO_OUTPUT_UNDERFLOW;
+      handle->xrun[0] = false;
+    }
+    if ( stream_.mode != OUTPUT && handle->xrun[1] == true ) {
+      status |= RTAUDIO_INPUT_OVERFLOW;
+      handle->xrun[1] = false;
+    }
+    int cbReturnValue = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                                  stream_.bufferSize, streamTime, status, info->userData );
+    if ( cbReturnValue == 2 ) {
+      stream_.state = STREAM_STOPPING;
+      handle->drainCounter = 2;
+      abortStream();
+      return;
+    }
+    else if ( cbReturnValue == 1 ) {
+      handle->drainCounter = 1;
+      handle->internalDrain = true;
+    }
+  }
+
+  HRESULT result;
+  DWORD currentWritePointer, safeWritePointer;
+  DWORD currentReadPointer, safeReadPointer;
+  UINT nextWritePointer;
+
+  LPVOID buffer1 = NULL;
+  LPVOID buffer2 = NULL;
+  DWORD bufferSize1 = 0;
+  DWORD bufferSize2 = 0;
+
+  char *buffer;
+  long bufferBytes;
+
+  MUTEX_LOCK( &stream_.mutex );
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_UNLOCK( &stream_.mutex );
+    return;
+  }
+
+  if ( buffersRolling == false ) {
+    if ( stream_.mode == DUPLEX ) {
+      //assert( handle->dsBufferSize[0] == handle->dsBufferSize[1] );
+
+      // It takes a while for the devices to get rolling. As a result,
+      // there's no guarantee that the capture and write device pointers
+      // will move in lockstep.  Wait here for both devices to start
+      // rolling, and then set our buffer pointers accordingly.
+      // e.g. Crystal Drivers: the capture buffer starts up 5700 to 9600
+      // bytes later than the write buffer.
+
+      // Stub: a serious risk of having a pre-emptive scheduling round
+      // take place between the two GetCurrentPosition calls... but I'm
+      // really not sure how to solve the problem.  Temporarily boost to
+      // Realtime priority, maybe; but I'm not sure what priority the
+      // DirectSound service threads run at. We *should* be roughly
+      // within a ms or so of correct.
+
+      LPDIRECTSOUNDBUFFER dsWriteBuffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+      LPDIRECTSOUNDCAPTUREBUFFER dsCaptureBuffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+
+      DWORD startSafeWritePointer, startSafeReadPointer;
+
+      result = dsWriteBuffer->GetCurrentPosition( NULL, &startSafeWritePointer );
+      if ( FAILED( result ) ) {
+        errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current write position!";
+        errorText_ = errorStream_.str();
+        MUTEX_UNLOCK( &stream_.mutex );
+        error( RtAudioError::SYSTEM_ERROR );
+        return;
+      }
+      result = dsCaptureBuffer->GetCurrentPosition( NULL, &startSafeReadPointer );
+      if ( FAILED( result ) ) {
+        errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current read position!";
+        errorText_ = errorStream_.str();
+        MUTEX_UNLOCK( &stream_.mutex );
+        error( RtAudioError::SYSTEM_ERROR );
+        return;
+      }
+      while ( true ) {
+        result = dsWriteBuffer->GetCurrentPosition( NULL, &safeWritePointer );
+        if ( FAILED( result ) ) {
+          errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current write position!";
+          errorText_ = errorStream_.str();
+          MUTEX_UNLOCK( &stream_.mutex );
+          error( RtAudioError::SYSTEM_ERROR );
+          return;
+        }
+        result = dsCaptureBuffer->GetCurrentPosition( NULL, &safeReadPointer );
+        if ( FAILED( result ) ) {
+          errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current read position!";
+          errorText_ = errorStream_.str();
+          MUTEX_UNLOCK( &stream_.mutex );
+          error( RtAudioError::SYSTEM_ERROR );
+          return;
+        }
+        if ( safeWritePointer != startSafeWritePointer && safeReadPointer != startSafeReadPointer ) break;
+        Sleep( 1 );
+      }
+
+      //assert( handle->dsBufferSize[0] == handle->dsBufferSize[1] );
+
+      handle->bufferPointer[0] = safeWritePointer + handle->dsPointerLeadTime[0];
+      if ( handle->bufferPointer[0] >= handle->dsBufferSize[0] ) handle->bufferPointer[0] -= handle->dsBufferSize[0];
+      handle->bufferPointer[1] = safeReadPointer;
+    }
+    else if ( stream_.mode == OUTPUT ) {
+
+      // Set the proper nextWritePosition after initial startup.
+      LPDIRECTSOUNDBUFFER dsWriteBuffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+      result = dsWriteBuffer->GetCurrentPosition( &currentWritePointer, &safeWritePointer );
+      if ( FAILED( result ) ) {
+        errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current write position!";
+        errorText_ = errorStream_.str();
+        MUTEX_UNLOCK( &stream_.mutex );
+        error( RtAudioError::SYSTEM_ERROR );
+        return;
+      }
+      handle->bufferPointer[0] = safeWritePointer + handle->dsPointerLeadTime[0];
+      if ( handle->bufferPointer[0] >= handle->dsBufferSize[0] ) handle->bufferPointer[0] -= handle->dsBufferSize[0];
+    }
+
+    buffersRolling = true;
+  }
+
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    
+    LPDIRECTSOUNDBUFFER dsBuffer = (LPDIRECTSOUNDBUFFER) handle->buffer[0];
+
+    if ( handle->drainCounter > 1 ) { // write zeros to the output stream
+      bufferBytes = stream_.bufferSize * stream_.nUserChannels[0];
+      bufferBytes *= formatBytes( stream_.userFormat );
+      memset( stream_.userBuffer[0], 0, bufferBytes );
+    }
+
+    // Setup parameters and do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[0] ) {
+      buffer = stream_.deviceBuffer;
+      convertBuffer( buffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+      bufferBytes = stream_.bufferSize * stream_.nDeviceChannels[0];
+      bufferBytes *= formatBytes( stream_.deviceFormat[0] );
+    }
+    else {
+      buffer = stream_.userBuffer[0];
+      bufferBytes = stream_.bufferSize * stream_.nUserChannels[0];
+      bufferBytes *= formatBytes( stream_.userFormat );
+    }
+
+    // No byte swapping necessary in DirectSound implementation.
+
+    // Ahhh ... windoze.  16-bit data is signed but 8-bit data is
+    // unsigned.  So, we need to convert our signed 8-bit data here to
+    // unsigned.
+    if ( stream_.deviceFormat[0] == RTAUDIO_SINT8 )
+      for ( int i=0; i<bufferBytes; i++ ) buffer[i] = (unsigned char) ( buffer[i] + 128 );
+
+    DWORD dsBufferSize = handle->dsBufferSize[0];
+    nextWritePointer = handle->bufferPointer[0];
+
+    DWORD endWrite, leadPointer;
+    while ( true ) {
+      // Find out where the read and "safe write" pointers are.
+      result = dsBuffer->GetCurrentPosition( &currentWritePointer, &safeWritePointer );
+      if ( FAILED( result ) ) {
+        errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current write position!";
+        errorText_ = errorStream_.str();
+        MUTEX_UNLOCK( &stream_.mutex );
+        error( RtAudioError::SYSTEM_ERROR );
+        return;
+      }
+
+      // We will copy our output buffer into the region between
+      // safeWritePointer and leadPointer.  If leadPointer is not
+      // beyond the next endWrite position, wait until it is.
+      leadPointer = safeWritePointer + handle->dsPointerLeadTime[0];
+      //std::cout << "safeWritePointer = " << safeWritePointer << ", leadPointer = " << leadPointer << ", nextWritePointer = " << nextWritePointer << std::endl;
+      if ( leadPointer > dsBufferSize ) leadPointer -= dsBufferSize;
+      if ( leadPointer < nextWritePointer ) leadPointer += dsBufferSize; // unwrap offset
+      endWrite = nextWritePointer + bufferBytes;
+
+      // Check whether the entire write region is behind the play pointer.
+      if ( leadPointer >= endWrite ) break;
+
+      // If we are here, then we must wait until the leadPointer advances
+      // beyond the end of our next write region. We use the
+      // Sleep() function to suspend operation until that happens.
+      double millis = ( endWrite - leadPointer ) * 1000.0;
+      millis /= ( formatBytes( stream_.deviceFormat[0]) * stream_.nDeviceChannels[0] * stream_.sampleRate);
+      if ( millis < 1.0 ) millis = 1.0;
+      Sleep( (DWORD) millis );
+    }
+
+    if ( dsPointerBetween( nextWritePointer, safeWritePointer, currentWritePointer, dsBufferSize )
+         || dsPointerBetween( endWrite, safeWritePointer, currentWritePointer, dsBufferSize ) ) { 
+      // We've strayed into the forbidden zone ... resync the read pointer.
+      handle->xrun[0] = true;
+      nextWritePointer = safeWritePointer + handle->dsPointerLeadTime[0] - bufferBytes;
+      if ( nextWritePointer >= dsBufferSize ) nextWritePointer -= dsBufferSize;
+      handle->bufferPointer[0] = nextWritePointer;
+      endWrite = nextWritePointer + bufferBytes;
+    }
+
+    // Lock free space in the buffer
+    result = dsBuffer->Lock( nextWritePointer, bufferBytes, &buffer1,
+                             &bufferSize1, &buffer2, &bufferSize2, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") locking buffer during playback!";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+
+    // Copy our buffer into the DS buffer
+    CopyMemory( buffer1, buffer, bufferSize1 );
+    if ( buffer2 != NULL ) CopyMemory( buffer2, buffer+bufferSize1, bufferSize2 );
+
+    // Update our buffer offset and unlock sound buffer
+    dsBuffer->Unlock( buffer1, bufferSize1, buffer2, bufferSize2 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") unlocking buffer during playback!";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+    nextWritePointer = ( nextWritePointer + bufferSize1 + bufferSize2 ) % dsBufferSize;
+    handle->bufferPointer[0] = nextWritePointer;
+  }
+
+  // Don't bother draining input
+  if ( handle->drainCounter ) {
+    handle->drainCounter++;
+    goto unlock;
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    // Setup parameters.
+    if ( stream_.doConvertBuffer[1] ) {
+      buffer = stream_.deviceBuffer;
+      bufferBytes = stream_.bufferSize * stream_.nDeviceChannels[1];
+      bufferBytes *= formatBytes( stream_.deviceFormat[1] );
+    }
+    else {
+      buffer = stream_.userBuffer[1];
+      bufferBytes = stream_.bufferSize * stream_.nUserChannels[1];
+      bufferBytes *= formatBytes( stream_.userFormat );
+    }
+
+    LPDIRECTSOUNDCAPTUREBUFFER dsBuffer = (LPDIRECTSOUNDCAPTUREBUFFER) handle->buffer[1];
+    long nextReadPointer = handle->bufferPointer[1];
+    DWORD dsBufferSize = handle->dsBufferSize[1];
+
+    // Find out where the write and "safe read" pointers are.
+    result = dsBuffer->GetCurrentPosition( &currentReadPointer, &safeReadPointer );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current read position!";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+
+    if ( safeReadPointer < (DWORD)nextReadPointer ) safeReadPointer += dsBufferSize; // unwrap offset
+    DWORD endRead = nextReadPointer + bufferBytes;
+
+    // Handling depends on whether we are INPUT or DUPLEX. 
+    // If we're in INPUT mode then waiting is a good thing. If we're in DUPLEX mode,
+    // then a wait here will drag the write pointers into the forbidden zone.
+    // 
+    // In DUPLEX mode, rather than wait, we will back off the read pointer until 
+    // it's in a safe position. This causes dropouts, but it seems to be the only 
+    // practical way to sync up the read and write pointers reliably, given the 
+    // the very complex relationship between phase and increment of the read and write 
+    // pointers.
+    //
+    // In order to minimize audible dropouts in DUPLEX mode, we will
+    // provide a pre-roll period of 0.5 seconds in which we return
+    // zeros from the read buffer while the pointers sync up.
+
+    if ( stream_.mode == DUPLEX ) {
+      if ( safeReadPointer < endRead ) {
+        if ( duplexPrerollBytes <= 0 ) {
+          // Pre-roll time over. Be more agressive.
+          int adjustment = endRead-safeReadPointer;
+
+          handle->xrun[1] = true;
+          // Two cases:
+          //   - large adjustments: we've probably run out of CPU cycles, so just resync exactly,
+          //     and perform fine adjustments later.
+          //   - small adjustments: back off by twice as much.
+          if ( adjustment >= 2*bufferBytes )
+            nextReadPointer = safeReadPointer-2*bufferBytes;
+          else
+            nextReadPointer = safeReadPointer-bufferBytes-adjustment;
+
+          if ( nextReadPointer < 0 ) nextReadPointer += dsBufferSize;
+
+        }
+        else {
+          // In pre=roll time. Just do it.
+          nextReadPointer = safeReadPointer - bufferBytes;
+          while ( nextReadPointer < 0 ) nextReadPointer += dsBufferSize;
+        }
+        endRead = nextReadPointer + bufferBytes;
+      }
+    }
+    else { // mode == INPUT
+      while ( safeReadPointer < endRead && stream_.callbackInfo.isRunning ) {
+        // See comments for playback.
+        double millis = (endRead - safeReadPointer) * 1000.0;
+        millis /= ( formatBytes(stream_.deviceFormat[1]) * stream_.nDeviceChannels[1] * stream_.sampleRate);
+        if ( millis < 1.0 ) millis = 1.0;
+        Sleep( (DWORD) millis );
+
+        // Wake up and find out where we are now.
+        result = dsBuffer->GetCurrentPosition( &currentReadPointer, &safeReadPointer );
+        if ( FAILED( result ) ) {
+          errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") getting current read position!";
+          errorText_ = errorStream_.str();
+          MUTEX_UNLOCK( &stream_.mutex );
+          error( RtAudioError::SYSTEM_ERROR );
+          return;
+        }
+      
+        if ( safeReadPointer < (DWORD)nextReadPointer ) safeReadPointer += dsBufferSize; // unwrap offset
+      }
+    }
+
+    // Lock free space in the buffer
+    result = dsBuffer->Lock( nextReadPointer, bufferBytes, &buffer1,
+                             &bufferSize1, &buffer2, &bufferSize2, 0 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") locking capture buffer!";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+
+    if ( duplexPrerollBytes <= 0 ) {
+      // Copy our buffer into the DS buffer
+      CopyMemory( buffer, buffer1, bufferSize1 );
+      if ( buffer2 != NULL ) CopyMemory( buffer+bufferSize1, buffer2, bufferSize2 );
+    }
+    else {
+      memset( buffer, 0, bufferSize1 );
+      if ( buffer2 != NULL ) memset( buffer + bufferSize1, 0, bufferSize2 );
+      duplexPrerollBytes -= bufferSize1 + bufferSize2;
+    }
+
+    // Update our buffer offset and unlock sound buffer
+    nextReadPointer = ( nextReadPointer + bufferSize1 + bufferSize2 ) % dsBufferSize;
+    dsBuffer->Unlock( buffer1, bufferSize1, buffer2, bufferSize2 );
+    if ( FAILED( result ) ) {
+      errorStream_ << "RtApiDs::callbackEvent: error (" << getErrorString( result ) << ") unlocking capture buffer!";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+    handle->bufferPointer[1] = nextReadPointer;
+
+    // No byte swapping necessary in DirectSound implementation.
+
+    // If necessary, convert 8-bit data from unsigned to signed.
+    if ( stream_.deviceFormat[1] == RTAUDIO_SINT8 )
+      for ( int j=0; j<bufferBytes; j++ ) buffer[j] = (signed char) ( buffer[j] - 128 );
+
+    // Do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[1] )
+      convertBuffer( stream_.userBuffer[1], stream_.deviceBuffer, stream_.convertInfo[1] );
+  }
+
+ unlock:
+  MUTEX_UNLOCK( &stream_.mutex );
+  RtApi::tickStreamTime();
+}
+
+// Definitions for utility functions and callbacks
+// specific to the DirectSound implementation.
+
+static unsigned __stdcall callbackHandler( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiDs *object = (RtApiDs *) info->object;
+  bool* isRunning = &info->isRunning;
+
+  while ( *isRunning == true ) {
+    object->callbackEvent();
+  }
+
+  _endthreadex( 0 );
+  return 0;
+}
+
+static BOOL CALLBACK deviceQueryCallback( LPGUID lpguid,
+                                          LPCTSTR description,
+                                          LPCTSTR /*module*/,
+                                          LPVOID lpContext )
+{
+  struct DsProbeData& probeInfo = *(struct DsProbeData*) lpContext;
+  std::vector<struct DsDevice>& dsDevices = *probeInfo.dsDevices;
+
+  HRESULT hr;
+  bool validDevice = false;
+  if ( probeInfo.isInput == true ) {
+    DSCCAPS caps;
+    LPDIRECTSOUNDCAPTURE object;
+
+    hr = DirectSoundCaptureCreate(  lpguid, &object,   NULL );
+    if ( hr != DS_OK ) return TRUE;
+
+    caps.dwSize = sizeof(caps);
+    hr = object->GetCaps( &caps );
+    if ( hr == DS_OK ) {
+      if ( caps.dwChannels > 0 && caps.dwFormats > 0 )
+        validDevice = true;
+    }
+    object->Release();
+  }
+  else {
+    DSCAPS caps;
+    LPDIRECTSOUND object;
+    hr = DirectSoundCreate(  lpguid, &object,   NULL );
+    if ( hr != DS_OK ) return TRUE;
+
+    caps.dwSize = sizeof(caps);
+    hr = object->GetCaps( &caps );
+    if ( hr == DS_OK ) {
+      if ( caps.dwFlags & DSCAPS_PRIMARYMONO || caps.dwFlags & DSCAPS_PRIMARYSTEREO )
+        validDevice = true;
+    }
+    object->Release();
+  }
+
+  // If good device, then save its name and guid.
+  std::string name = convertCharPointerToStdString( description );
+  //if ( name == "Primary Sound Driver" || name == "Primary Sound Capture Driver" )
+  if ( lpguid == NULL )
+    name = "Default Device";
+  if ( validDevice ) {
+    for ( unsigned int i=0; i<dsDevices.size(); i++ ) {
+      if ( dsDevices[i].name == name ) {
+        dsDevices[i].found = true;
+        if ( probeInfo.isInput ) {
+          dsDevices[i].id[1] = lpguid;
+          dsDevices[i].validId[1] = true;
+        }
+        else {
+          dsDevices[i].id[0] = lpguid;
+          dsDevices[i].validId[0] = true;
+        }
+        return TRUE;
+      }
+    }
+
+    DsDevice device;
+    device.name = name;
+    device.found = true;
+    if ( probeInfo.isInput ) {
+      device.id[1] = lpguid;
+      device.validId[1] = true;
+    }
+    else {
+      device.id[0] = lpguid;
+      device.validId[0] = true;
+    }
+    dsDevices.push_back( device );
+  }
+
+  return TRUE;
+}
+
+static const char* getErrorString( int code )
+{
+  switch ( code ) {
+
+  case DSERR_ALLOCATED:
+    return "Already allocated";
+
+  case DSERR_CONTROLUNAVAIL:
+    return "Control unavailable";
+
+  case DSERR_INVALIDPARAM:
+    return "Invalid parameter";
+
+  case DSERR_INVALIDCALL:
+    return "Invalid call";
+
+  case DSERR_GENERIC:
+    return "Generic error";
+
+  case DSERR_PRIOLEVELNEEDED:
+    return "Priority level needed";
+
+  case DSERR_OUTOFMEMORY:
+    return "Out of memory";
+
+  case DSERR_BADFORMAT:
+    return "The sample rate or the channel format is not supported";
+
+  case DSERR_UNSUPPORTED:
+    return "Not supported";
+
+  case DSERR_NODRIVER:
+    return "No driver";
+
+  case DSERR_ALREADYINITIALIZED:
+    return "Already initialized";
+
+  case DSERR_NOAGGREGATION:
+    return "No aggregation";
+
+  case DSERR_BUFFERLOST:
+    return "Buffer lost";
+
+  case DSERR_OTHERAPPHASPRIO:
+    return "Another application already has priority";
+
+  case DSERR_UNINITIALIZED:
+    return "Uninitialized";
+
+  default:
+    return "DirectSound unknown error";
+  }
+}
+//******************** End of __WINDOWS_DS__ *********************//
+#endif
+
+
+#if defined(__LINUX_ALSA__)
+
+#include <alsa/asoundlib.h>
+#include <unistd.h>
+
+  // A structure to hold various information related to the ALSA API
+  // implementation.
+struct AlsaHandle {
+  snd_pcm_t *handles[2];
+  bool synchronized;
+  bool xrun[2];
+  pthread_cond_t runnable_cv;
+  bool runnable;
+
+  AlsaHandle()
+    :synchronized(false), runnable(false) { xrun[0] = false; xrun[1] = false; }
+};
+
+static void *alsaCallbackHandler( void * ptr );
+
+RtApiAlsa :: RtApiAlsa()
+{
+  // Nothing to do here.
+}
+
+RtApiAlsa :: ~RtApiAlsa()
+{
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+}
+
+unsigned int RtApiAlsa :: getDeviceCount( void )
+{
+  unsigned nDevices = 0;
+  int result, subdevice, card;
+  char name[64];
+  snd_ctl_t *handle;
+
+  // Count cards and devices
+  card = -1;
+  snd_card_next( &card );
+  while ( card >= 0 ) {
+    sprintf( name, "hw:%d", card );
+    result = snd_ctl_open( &handle, name, 0 );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::getDeviceCount: control open, card = " << card << ", " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      error( RtAudioError::WARNING );
+      goto nextcard;
+    }
+    subdevice = -1;
+    while( 1 ) {
+      result = snd_ctl_pcm_next_device( handle, &subdevice );
+      if ( result < 0 ) {
+        errorStream_ << "RtApiAlsa::getDeviceCount: control next device, card = " << card << ", " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+        error( RtAudioError::WARNING );
+        break;
+      }
+      if ( subdevice < 0 )
+        break;
+      nDevices++;
+    }
+  nextcard:
+    snd_ctl_close( handle );
+    snd_card_next( &card );
+  }
+
+  result = snd_ctl_open( &handle, "default", 0 );
+  if (result == 0) {
+    nDevices++;
+    snd_ctl_close( handle );
+  }
+
+  return nDevices;
+}
+
+RtAudio::DeviceInfo RtApiAlsa :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  unsigned nDevices = 0;
+  int result, subdevice, card;
+  char name[64];
+  snd_ctl_t *chandle;
+
+  // Count cards and devices
+  card = -1;
+  subdevice = -1;
+  snd_card_next( &card );
+  while ( card >= 0 ) {
+    sprintf( name, "hw:%d", card );
+    result = snd_ctl_open( &chandle, name, SND_CTL_NONBLOCK );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::getDeviceInfo: control open, card = " << card << ", " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      error( RtAudioError::WARNING );
+      goto nextcard;
+    }
+    subdevice = -1;
+    while( 1 ) {
+      result = snd_ctl_pcm_next_device( chandle, &subdevice );
+      if ( result < 0 ) {
+        errorStream_ << "RtApiAlsa::getDeviceInfo: control next device, card = " << card << ", " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+        error( RtAudioError::WARNING );
+        break;
+      }
+      if ( subdevice < 0 ) break;
+      if ( nDevices == device ) {
+        sprintf( name, "hw:%d,%d", card, subdevice );
+        goto foundDevice;
+      }
+      nDevices++;
+    }
+  nextcard:
+    snd_ctl_close( chandle );
+    snd_card_next( &card );
+  }
+
+  result = snd_ctl_open( &chandle, "default", SND_CTL_NONBLOCK );
+  if ( result == 0 ) {
+    if ( nDevices == device ) {
+      strcpy( name, "default" );
+      goto foundDevice;
+    }
+    nDevices++;
+  }
+
+  if ( nDevices == 0 ) {
+    errorText_ = "RtApiAlsa::getDeviceInfo: no devices found!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  if ( device >= nDevices ) {
+    errorText_ = "RtApiAlsa::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+ foundDevice:
+
+  // If a stream is already open, we cannot probe the stream devices.
+  // Thus, use the saved results.
+  if ( stream_.state != STREAM_CLOSED &&
+       ( stream_.device[0] == device || stream_.device[1] == device ) ) {
+    snd_ctl_close( chandle );
+    if ( device >= devices_.size() ) {
+      errorText_ = "RtApiAlsa::getDeviceInfo: device ID was not present before stream was opened.";
+      error( RtAudioError::WARNING );
+      return info;
+    }
+    return devices_[ device ];
+  }
+
+  int openMode = SND_PCM_ASYNC;
+  snd_pcm_stream_t stream;
+  snd_pcm_info_t *pcminfo;
+  snd_pcm_info_alloca( &pcminfo );
+  snd_pcm_t *phandle;
+  snd_pcm_hw_params_t *params;
+  snd_pcm_hw_params_alloca( &params );
+
+  // First try for playback unless default device (which has subdev -1)
+  stream = SND_PCM_STREAM_PLAYBACK;
+  snd_pcm_info_set_stream( pcminfo, stream );
+  if ( subdevice != -1 ) {
+    snd_pcm_info_set_device( pcminfo, subdevice );
+    snd_pcm_info_set_subdevice( pcminfo, 0 );
+
+    result = snd_ctl_pcm_info( chandle, pcminfo );
+    if ( result < 0 ) {
+      // Device probably doesn't support playback.
+      goto captureProbe;
+    }
+  }
+
+  result = snd_pcm_open( &phandle, name, stream, openMode | SND_PCM_NONBLOCK );
+  if ( result < 0 ) {
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    goto captureProbe;
+  }
+
+  // The device is open ... fill the parameter structure.
+  result = snd_pcm_hw_params_any( phandle, params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_hw_params error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    goto captureProbe;
+  }
+
+  // Get output channel information.
+  unsigned int value;
+  result = snd_pcm_hw_params_get_channels_max( params, &value );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: error getting device (" << name << ") output channels, " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    goto captureProbe;
+  }
+  info.outputChannels = value;
+  snd_pcm_close( phandle );
+
+ captureProbe:
+  stream = SND_PCM_STREAM_CAPTURE;
+  snd_pcm_info_set_stream( pcminfo, stream );
+
+  // Now try for capture unless default device (with subdev = -1)
+  if ( subdevice != -1 ) {
+    result = snd_ctl_pcm_info( chandle, pcminfo );
+    snd_ctl_close( chandle );
+    if ( result < 0 ) {
+      // Device probably doesn't support capture.
+      if ( info.outputChannels == 0 ) return info;
+      goto probeParameters;
+    }
+  }
+  else
+    snd_ctl_close( chandle );
+
+  result = snd_pcm_open( &phandle, name, stream, openMode | SND_PCM_NONBLOCK);
+  if ( result < 0 ) {
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    if ( info.outputChannels == 0 ) return info;
+    goto probeParameters;
+  }
+
+  // The device is open ... fill the parameter structure.
+  result = snd_pcm_hw_params_any( phandle, params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_hw_params error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    if ( info.outputChannels == 0 ) return info;
+    goto probeParameters;
+  }
+
+  result = snd_pcm_hw_params_get_channels_max( params, &value );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: error getting device (" << name << ") input channels, " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    if ( info.outputChannels == 0 ) return info;
+    goto probeParameters;
+  }
+  info.inputChannels = value;
+  snd_pcm_close( phandle );
+
+  // If device opens for both playback and capture, we determine the channels.
+  if ( info.outputChannels > 0 && info.inputChannels > 0 )
+    info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+
+  // ALSA doesn't provide default devices so we'll use the first available one.
+  if ( device == 0 && info.outputChannels > 0 )
+    info.isDefaultOutput = true;
+  if ( device == 0 && info.inputChannels > 0 )
+    info.isDefaultInput = true;
+
+ probeParameters:
+  // At this point, we just need to figure out the supported data
+  // formats and sample rates.  We'll proceed by opening the device in
+  // the direction with the maximum number of channels, or playback if
+  // they are equal.  This might limit our sample rate options, but so
+  // be it.
+
+  if ( info.outputChannels >= info.inputChannels )
+    stream = SND_PCM_STREAM_PLAYBACK;
+  else
+    stream = SND_PCM_STREAM_CAPTURE;
+  snd_pcm_info_set_stream( pcminfo, stream );
+
+  result = snd_pcm_open( &phandle, name, stream, openMode | SND_PCM_NONBLOCK);
+  if ( result < 0 ) {
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_open error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // The device is open ... fill the parameter structure.
+  result = snd_pcm_hw_params_any( phandle, params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: snd_pcm_hw_params error for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Test our discrete set of sample rate values.
+  info.sampleRates.clear();
+  for ( unsigned int i=0; i<MAX_SAMPLE_RATES; i++ ) {
+    if ( snd_pcm_hw_params_test_rate( phandle, params, SAMPLE_RATES[i], 0 ) == 0 ) {
+      info.sampleRates.push_back( SAMPLE_RATES[i] );
+
+      if ( !info.preferredSampleRate || ( SAMPLE_RATES[i] <= 48000 && SAMPLE_RATES[i] > info.preferredSampleRate ) )
+        info.preferredSampleRate = SAMPLE_RATES[i];
+    }
+  }
+  if ( info.sampleRates.size() == 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: no supported sample rates found for device (" << name << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Probe the supported data formats ... we don't care about endian-ness just yet
+  snd_pcm_format_t format;
+  info.nativeFormats = 0;
+  format = SND_PCM_FORMAT_S8;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_SINT8;
+  format = SND_PCM_FORMAT_S16;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_SINT16;
+  format = SND_PCM_FORMAT_S24;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_SINT24;
+  format = SND_PCM_FORMAT_S32;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_SINT32;
+  format = SND_PCM_FORMAT_FLOAT;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_FLOAT32;
+  format = SND_PCM_FORMAT_FLOAT64;
+  if ( snd_pcm_hw_params_test_format( phandle, params, format ) == 0 )
+    info.nativeFormats |= RTAUDIO_FLOAT64;
+
+  // Check that we have at least one supported format
+  if ( info.nativeFormats == 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::getDeviceInfo: pcm device (" << name << ") data format not supported by RtAudio.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Get the device name
+  char *cardname;
+  result = snd_card_get_name( card, &cardname );
+  if ( result >= 0 ) {
+    sprintf( name, "hw:%s,%d", cardname, subdevice );
+    free( cardname );
+  }
+  info.name = name;
+
+  // That's all ... close the device and return
+  snd_pcm_close( phandle );
+  info.probed = true;
+  return info;
+}
+
+void RtApiAlsa :: saveDeviceInfo( void )
+{
+  devices_.clear();
+
+  unsigned int nDevices = getDeviceCount();
+  devices_.resize( nDevices );
+  for ( unsigned int i=0; i<nDevices; i++ )
+    devices_[i] = getDeviceInfo( i );
+}
+
+bool RtApiAlsa :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                   unsigned int firstChannel, unsigned int sampleRate,
+                                   RtAudioFormat format, unsigned int *bufferSize,
+                                   RtAudio::StreamOptions *options )
+
+{
+#if defined(__RTAUDIO_DEBUG__)
+  snd_output_t *out;
+  snd_output_stdio_attach(&out, stderr, 0);
+#endif
+
+  // I'm not using the "plug" interface ... too much inconsistent behavior.
+
+  unsigned nDevices = 0;
+  int result, subdevice, card;
+  char name[64];
+  snd_ctl_t *chandle;
+
+  if ( options && options->flags & RTAUDIO_ALSA_USE_DEFAULT )
+    snprintf(name, sizeof(name), "%s", "default");
+  else {
+    // Count cards and devices
+    card = -1;
+    snd_card_next( &card );
+    while ( card >= 0 ) {
+      sprintf( name, "hw:%d", card );
+      result = snd_ctl_open( &chandle, name, SND_CTL_NONBLOCK );
+      if ( result < 0 ) {
+        errorStream_ << "RtApiAlsa::probeDeviceOpen: control open, card = " << card << ", " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+        return FAILURE;
+      }
+      subdevice = -1;
+      while( 1 ) {
+        result = snd_ctl_pcm_next_device( chandle, &subdevice );
+        if ( result < 0 ) break;
+        if ( subdevice < 0 ) break;
+        if ( nDevices == device ) {
+          sprintf( name, "hw:%d,%d", card, subdevice );
+          snd_ctl_close( chandle );
+          goto foundDevice;
+        }
+        nDevices++;
+      }
+      snd_ctl_close( chandle );
+      snd_card_next( &card );
+    }
+
+    result = snd_ctl_open( &chandle, "default", SND_CTL_NONBLOCK );
+    if ( result == 0 ) {
+      if ( nDevices == device ) {
+        strcpy( name, "default" );
+        goto foundDevice;
+      }
+      nDevices++;
+    }
+
+    if ( nDevices == 0 ) {
+      // This should not happen because a check is made before this function is called.
+      errorText_ = "RtApiAlsa::probeDeviceOpen: no devices found!";
+      return FAILURE;
+    }
+
+    if ( device >= nDevices ) {
+      // This should not happen because a check is made before this function is called.
+      errorText_ = "RtApiAlsa::probeDeviceOpen: device ID is invalid!";
+      return FAILURE;
+    }
+  }
+
+ foundDevice:
+
+  // The getDeviceInfo() function will not work for a device that is
+  // already open.  Thus, we'll probe the system before opening a
+  // stream and save the results for use by getDeviceInfo().
+  if ( mode == OUTPUT || ( mode == INPUT && stream_.mode != OUTPUT ) ) // only do once
+    this->saveDeviceInfo();
+
+  snd_pcm_stream_t stream;
+  if ( mode == OUTPUT )
+    stream = SND_PCM_STREAM_PLAYBACK;
+  else
+    stream = SND_PCM_STREAM_CAPTURE;
+
+  snd_pcm_t *phandle;
+  int openMode = SND_PCM_ASYNC;
+  result = snd_pcm_open( &phandle, name, stream, openMode );
+  if ( result < 0 ) {
+    if ( mode == OUTPUT )
+      errorStream_ << "RtApiAlsa::probeDeviceOpen: pcm device (" << name << ") won't open for output.";
+    else
+      errorStream_ << "RtApiAlsa::probeDeviceOpen: pcm device (" << name << ") won't open for input.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Fill the parameter structure.
+  snd_pcm_hw_params_t *hw_params;
+  snd_pcm_hw_params_alloca( &hw_params );
+  result = snd_pcm_hw_params_any( phandle, hw_params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error getting pcm device (" << name << ") parameters, " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+#if defined(__RTAUDIO_DEBUG__)
+  fprintf( stderr, "\nRtApiAlsa: dump hardware params just after device open:\n\n" );
+  snd_pcm_hw_params_dump( hw_params, out );
+#endif
+
+  // Set access ... check user preference.
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) {
+    stream_.userInterleaved = false;
+    result = snd_pcm_hw_params_set_access( phandle, hw_params, SND_PCM_ACCESS_RW_NONINTERLEAVED );
+    if ( result < 0 ) {
+      result = snd_pcm_hw_params_set_access( phandle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED );
+      stream_.deviceInterleaved[mode] =  true;
+    }
+    else
+      stream_.deviceInterleaved[mode] = false;
+  }
+  else {
+    stream_.userInterleaved = true;
+    result = snd_pcm_hw_params_set_access( phandle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED );
+    if ( result < 0 ) {
+      result = snd_pcm_hw_params_set_access( phandle, hw_params, SND_PCM_ACCESS_RW_NONINTERLEAVED );
+      stream_.deviceInterleaved[mode] =  false;
+    }
+    else
+      stream_.deviceInterleaved[mode] =  true;
+  }
+
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting pcm device (" << name << ") access, " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Determine how to set the device format.
+  stream_.userFormat = format;
+  snd_pcm_format_t deviceFormat = SND_PCM_FORMAT_UNKNOWN;
+
+  if ( format == RTAUDIO_SINT8 )
+    deviceFormat = SND_PCM_FORMAT_S8;
+  else if ( format == RTAUDIO_SINT16 )
+    deviceFormat = SND_PCM_FORMAT_S16;
+  else if ( format == RTAUDIO_SINT24 )
+    deviceFormat = SND_PCM_FORMAT_S24;
+  else if ( format == RTAUDIO_SINT32 )
+    deviceFormat = SND_PCM_FORMAT_S32;
+  else if ( format == RTAUDIO_FLOAT32 )
+    deviceFormat = SND_PCM_FORMAT_FLOAT;
+  else if ( format == RTAUDIO_FLOAT64 )
+    deviceFormat = SND_PCM_FORMAT_FLOAT64;
+
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat) == 0) {
+    stream_.deviceFormat[mode] = format;
+    goto setFormat;
+  }
+
+  // The user requested format is not natively supported by the device.
+  deviceFormat = SND_PCM_FORMAT_FLOAT64;
+  if ( snd_pcm_hw_params_test_format( phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_FLOAT64;
+    goto setFormat;
+  }
+
+  deviceFormat = SND_PCM_FORMAT_FLOAT;
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_FLOAT32;
+    goto setFormat;
+  }
+
+  deviceFormat = SND_PCM_FORMAT_S32;
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+    goto setFormat;
+  }
+
+  deviceFormat = SND_PCM_FORMAT_S24;
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+    goto setFormat;
+  }
+
+  deviceFormat = SND_PCM_FORMAT_S16;
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+    goto setFormat;
+  }
+
+  deviceFormat = SND_PCM_FORMAT_S8;
+  if ( snd_pcm_hw_params_test_format(phandle, hw_params, deviceFormat ) == 0 ) {
+    stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+    goto setFormat;
+  }
+
+  // If we get here, no supported format was found.
+  snd_pcm_close( phandle );
+  errorStream_ << "RtApiAlsa::probeDeviceOpen: pcm device " << device << " data format not supported by RtAudio.";
+  errorText_ = errorStream_.str();
+  return FAILURE;
+
+ setFormat:
+  result = snd_pcm_hw_params_set_format( phandle, hw_params, deviceFormat );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting pcm device (" << name << ") data format, " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Determine whether byte-swaping is necessary.
+  stream_.doByteSwap[mode] = false;
+  if ( deviceFormat != SND_PCM_FORMAT_S8 ) {
+    result = snd_pcm_format_cpu_endian( deviceFormat );
+    if ( result == 0 )
+      stream_.doByteSwap[mode] = true;
+    else if (result < 0) {
+      snd_pcm_close( phandle );
+      errorStream_ << "RtApiAlsa::probeDeviceOpen: error getting pcm device (" << name << ") endian-ness, " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      return FAILURE;
+    }
+  }
+
+  // Set the sample rate.
+  result = snd_pcm_hw_params_set_rate_near( phandle, hw_params, (unsigned int*) &sampleRate, 0 );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting sample rate on device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Determine the number of channels for this device.  We support a possible
+  // minimum device channel number > than the value requested by the user.
+  stream_.nUserChannels[mode] = channels;
+  unsigned int value;
+  result = snd_pcm_hw_params_get_channels_max( hw_params, &value );
+  unsigned int deviceChannels = value;
+  if ( result < 0 || deviceChannels < channels + firstChannel ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: requested channel parameters not supported by device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  result = snd_pcm_hw_params_get_channels_min( hw_params, &value );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error getting minimum channels for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  deviceChannels = value;
+  if ( deviceChannels < channels + firstChannel ) deviceChannels = channels + firstChannel;
+  stream_.nDeviceChannels[mode] = deviceChannels;
+
+  // Set the device channels.
+  result = snd_pcm_hw_params_set_channels( phandle, hw_params, deviceChannels );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting channels for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Set the buffer (or period) size.
+  int dir = 0;
+  snd_pcm_uframes_t periodSize = *bufferSize;
+  result = snd_pcm_hw_params_set_period_size_near( phandle, hw_params, &periodSize, &dir );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting period size for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  *bufferSize = periodSize;
+
+  // Set the buffer number, which in ALSA is referred to as the "period".
+  unsigned int periods = 0;
+  if ( options && options->flags & RTAUDIO_MINIMIZE_LATENCY ) periods = 2;
+  if ( options && options->numberOfBuffers > 0 ) periods = options->numberOfBuffers;
+  if ( periods < 2 ) periods = 4; // a fairly safe default value
+  result = snd_pcm_hw_params_set_periods_near( phandle, hw_params, &periods, &dir );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error setting periods for device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // If attempting to setup a duplex stream, the bufferSize parameter
+  // MUST be the same in both directions!
+  if ( stream_.mode == OUTPUT && mode == INPUT && *bufferSize != stream_.bufferSize ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: system error setting buffer size for duplex stream on device (" << name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  stream_.bufferSize = *bufferSize;
+
+  // Install the hardware configuration
+  result = snd_pcm_hw_params( phandle, hw_params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error installing hardware configuration on device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+#if defined(__RTAUDIO_DEBUG__)
+  fprintf(stderr, "\nRtApiAlsa: dump hardware params after installation:\n\n");
+  snd_pcm_hw_params_dump( hw_params, out );
+#endif
+
+  // Set the software configuration to fill buffers with zeros and prevent device stopping on xruns.
+  snd_pcm_sw_params_t *sw_params = NULL;
+  snd_pcm_sw_params_alloca( &sw_params );
+  snd_pcm_sw_params_current( phandle, sw_params );
+  snd_pcm_sw_params_set_start_threshold( phandle, sw_params, *bufferSize );
+  snd_pcm_sw_params_set_stop_threshold( phandle, sw_params, ULONG_MAX );
+  snd_pcm_sw_params_set_silence_threshold( phandle, sw_params, 0 );
+
+  // The following two settings were suggested by Theo Veenker
+  //snd_pcm_sw_params_set_avail_min( phandle, sw_params, *bufferSize );
+  //snd_pcm_sw_params_set_xfer_align( phandle, sw_params, 1 );
+
+  // here are two options for a fix
+  //snd_pcm_sw_params_set_silence_size( phandle, sw_params, ULONG_MAX );
+  snd_pcm_uframes_t val;
+  snd_pcm_sw_params_get_boundary( sw_params, &val );
+  snd_pcm_sw_params_set_silence_size( phandle, sw_params, val );
+
+  result = snd_pcm_sw_params( phandle, sw_params );
+  if ( result < 0 ) {
+    snd_pcm_close( phandle );
+    errorStream_ << "RtApiAlsa::probeDeviceOpen: error installing software configuration on device (" << name << "), " << snd_strerror( result ) << ".";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+#if defined(__RTAUDIO_DEBUG__)
+  fprintf(stderr, "\nRtApiAlsa: dump software params after installation:\n\n");
+  snd_pcm_sw_params_dump( sw_params, out );
+#endif
+
+  // Set flags for buffer conversion
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.nUserChannels[mode] < stream_.nDeviceChannels[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+       stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate the ApiHandle if necessary and then save.
+  AlsaHandle *apiInfo = 0;
+  if ( stream_.apiHandle == 0 ) {
+    try {
+      apiInfo = (AlsaHandle *) new AlsaHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiAlsa::probeDeviceOpen: error allocating AlsaHandle memory.";
+      goto error;
+    }
+
+    if ( pthread_cond_init( &apiInfo->runnable_cv, NULL ) ) {
+      errorText_ = "RtApiAlsa::probeDeviceOpen: error initializing pthread condition variable.";
+      goto error;
+    }
+
+    stream_.apiHandle = (void *) apiInfo;
+    apiInfo->handles[0] = 0;
+    apiInfo->handles[1] = 0;
+  }
+  else {
+    apiInfo = (AlsaHandle *) stream_.apiHandle;
+  }
+  apiInfo->handles[mode] = phandle;
+  phandle = 0;
+
+  // Allocate necessary internal buffers.
+  unsigned long bufferBytes;
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiAlsa::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( mode == INPUT ) {
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+        if ( bufferBytes <= bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiAlsa::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  stream_.sampleRate = sampleRate;
+  stream_.nBuffers = periods;
+  stream_.device[mode] = device;
+  stream_.state = STREAM_STOPPED;
+
+  // Setup the buffer conversion information structure.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, firstChannel );
+
+  // Setup thread if necessary.
+  if ( stream_.mode == OUTPUT && mode == INPUT ) {
+    // We had already set up an output stream.
+    stream_.mode = DUPLEX;
+    // Link the streams if possible.
+    apiInfo->synchronized = false;
+    if ( snd_pcm_link( apiInfo->handles[0], apiInfo->handles[1] ) == 0 )
+      apiInfo->synchronized = true;
+    else {
+      errorText_ = "RtApiAlsa::probeDeviceOpen: unable to synchronize input and output devices.";
+      error( RtAudioError::WARNING );
+    }
+  }
+  else {
+    stream_.mode = mode;
+
+    // Setup callback thread.
+    stream_.callbackInfo.object = (void *) this;
+
+    // Set the thread attributes for joinable and realtime scheduling
+    // priority (optional).  The higher priority will only take affect
+    // if the program is run as root or suid. Note, under Linux
+    // processes with CAP_SYS_NICE privilege, a user can change
+    // scheduling policy and priority (thus need not be root). See
+    // POSIX "capabilities".
+    pthread_attr_t attr;
+    pthread_attr_init( &attr );
+    pthread_attr_setdetachstate( &attr, PTHREAD_CREATE_JOINABLE );
+
+#ifdef SCHED_RR // Undefined with some OSes (eg: NetBSD 1.6.x with GNU Pthread)
+    if ( options && options->flags & RTAUDIO_SCHEDULE_REALTIME ) {
+      // We previously attempted to increase the audio callback priority
+      // to SCHED_RR here via the attributes.  However, while no errors
+      // were reported in doing so, it did not work.  So, now this is
+      // done in the alsaCallbackHandler function.
+      stream_.callbackInfo.doRealtime = true;
+      int priority = options->priority;
+      int min = sched_get_priority_min( SCHED_RR );
+      int max = sched_get_priority_max( SCHED_RR );
+      if ( priority < min ) priority = min;
+      else if ( priority > max ) priority = max;
+      stream_.callbackInfo.priority = priority;
+    }
+#endif
+
+    stream_.callbackInfo.isRunning = true;
+    result = pthread_create( &stream_.callbackInfo.thread, &attr, alsaCallbackHandler, &stream_.callbackInfo );
+    pthread_attr_destroy( &attr );
+    if ( result ) {
+      stream_.callbackInfo.isRunning = false;
+      errorText_ = "RtApiAlsa::error creating callback thread!";
+      goto error;
+    }
+  }
+
+  return SUCCESS;
+
+ error:
+  if ( apiInfo ) {
+    pthread_cond_destroy( &apiInfo->runnable_cv );
+    if ( apiInfo->handles[0] ) snd_pcm_close( apiInfo->handles[0] );
+    if ( apiInfo->handles[1] ) snd_pcm_close( apiInfo->handles[1] );
+    delete apiInfo;
+    stream_.apiHandle = 0;
+  }
+
+  if ( phandle) snd_pcm_close( phandle );
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.state = STREAM_CLOSED;
+  return FAILURE;
+}
+
+void RtApiAlsa :: closeStream()
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiAlsa::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  AlsaHandle *apiInfo = (AlsaHandle *) stream_.apiHandle;
+  stream_.callbackInfo.isRunning = false;
+  MUTEX_LOCK( &stream_.mutex );
+  if ( stream_.state == STREAM_STOPPED ) {
+    apiInfo->runnable = true;
+    pthread_cond_signal( &apiInfo->runnable_cv );
+  }
+  MUTEX_UNLOCK( &stream_.mutex );
+  pthread_join( stream_.callbackInfo.thread, NULL );
+
+  if ( stream_.state == STREAM_RUNNING ) {
+    stream_.state = STREAM_STOPPED;
+    if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX )
+      snd_pcm_drop( apiInfo->handles[0] );
+    if ( stream_.mode == INPUT || stream_.mode == DUPLEX )
+      snd_pcm_drop( apiInfo->handles[1] );
+  }
+
+  if ( apiInfo ) {
+    pthread_cond_destroy( &apiInfo->runnable_cv );
+    if ( apiInfo->handles[0] ) snd_pcm_close( apiInfo->handles[0] );
+    if ( apiInfo->handles[1] ) snd_pcm_close( apiInfo->handles[1] );
+    delete apiInfo;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+void RtApiAlsa :: startStream()
+{
+  // This method calls snd_pcm_prepare if the device isn't already in that state.
+
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiAlsa::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  int result = 0;
+  snd_pcm_state_t state;
+  AlsaHandle *apiInfo = (AlsaHandle *) stream_.apiHandle;
+  snd_pcm_t **handle = (snd_pcm_t **) apiInfo->handles;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    state = snd_pcm_state( handle[0] );
+    if ( state != SND_PCM_STATE_PREPARED ) {
+      result = snd_pcm_prepare( handle[0] );
+      if ( result < 0 ) {
+        errorStream_ << "RtApiAlsa::startStream: error preparing output pcm device, " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+        goto unlock;
+      }
+    }
+  }
+
+  if ( ( stream_.mode == INPUT || stream_.mode == DUPLEX ) && !apiInfo->synchronized ) {
+    result = snd_pcm_drop(handle[1]); // fix to remove stale data received since device has been open
+    state = snd_pcm_state( handle[1] );
+    if ( state != SND_PCM_STATE_PREPARED ) {
+      result = snd_pcm_prepare( handle[1] );
+      if ( result < 0 ) {
+        errorStream_ << "RtApiAlsa::startStream: error preparing input pcm device, " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+        goto unlock;
+      }
+    }
+  }
+
+  stream_.state = STREAM_RUNNING;
+
+ unlock:
+  apiInfo->runnable = true;
+  pthread_cond_signal( &apiInfo->runnable_cv );
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( result >= 0 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiAlsa :: stopStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiAlsa::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_LOCK( &stream_.mutex );
+
+  int result = 0;
+  AlsaHandle *apiInfo = (AlsaHandle *) stream_.apiHandle;
+  snd_pcm_t **handle = (snd_pcm_t **) apiInfo->handles;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    if ( apiInfo->synchronized ) 
+      result = snd_pcm_drop( handle[0] );
+    else
+      result = snd_pcm_drain( handle[0] );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::stopStream: error draining output pcm device, " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  if ( ( stream_.mode == INPUT || stream_.mode == DUPLEX ) && !apiInfo->synchronized ) {
+    result = snd_pcm_drop( handle[1] );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::stopStream: error stopping input pcm device, " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+ unlock:
+  apiInfo->runnable = false; // fixes high CPU usage when stopped
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( result >= 0 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiAlsa :: abortStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiAlsa::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_LOCK( &stream_.mutex );
+
+  int result = 0;
+  AlsaHandle *apiInfo = (AlsaHandle *) stream_.apiHandle;
+  snd_pcm_t **handle = (snd_pcm_t **) apiInfo->handles;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    result = snd_pcm_drop( handle[0] );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::abortStream: error aborting output pcm device, " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+  if ( ( stream_.mode == INPUT || stream_.mode == DUPLEX ) && !apiInfo->synchronized ) {
+    result = snd_pcm_drop( handle[1] );
+    if ( result < 0 ) {
+      errorStream_ << "RtApiAlsa::abortStream: error aborting input pcm device, " << snd_strerror( result ) << ".";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+ unlock:
+  apiInfo->runnable = false; // fixes high CPU usage when stopped
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( result >= 0 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiAlsa :: callbackEvent()
+{
+  AlsaHandle *apiInfo = (AlsaHandle *) stream_.apiHandle;
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_LOCK( &stream_.mutex );
+    while ( !apiInfo->runnable )
+      pthread_cond_wait( &apiInfo->runnable_cv, &stream_.mutex );
+
+    if ( stream_.state != STREAM_RUNNING ) {
+      MUTEX_UNLOCK( &stream_.mutex );
+      return;
+    }
+    MUTEX_UNLOCK( &stream_.mutex );
+  }
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiAlsa::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  int doStopStream = 0;
+  RtAudioCallback callback = (RtAudioCallback) stream_.callbackInfo.callback;
+  double streamTime = getStreamTime();
+  RtAudioStreamStatus status = 0;
+  if ( stream_.mode != INPUT && apiInfo->xrun[0] == true ) {
+    status |= RTAUDIO_OUTPUT_UNDERFLOW;
+    apiInfo->xrun[0] = false;
+  }
+  if ( stream_.mode != OUTPUT && apiInfo->xrun[1] == true ) {
+    status |= RTAUDIO_INPUT_OVERFLOW;
+    apiInfo->xrun[1] = false;
+  }
+  doStopStream = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                           stream_.bufferSize, streamTime, status, stream_.callbackInfo.userData );
+
+  if ( doStopStream == 2 ) {
+    abortStream();
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  // The state might change while waiting on a mutex.
+  if ( stream_.state == STREAM_STOPPED ) goto unlock;
+
+  int result;
+  char *buffer;
+  int channels;
+  snd_pcm_t **handle;
+  snd_pcm_sframes_t frames;
+  RtAudioFormat format;
+  handle = (snd_pcm_t **) apiInfo->handles;
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    // Setup parameters.
+    if ( stream_.doConvertBuffer[1] ) {
+      buffer = stream_.deviceBuffer;
+      channels = stream_.nDeviceChannels[1];
+      format = stream_.deviceFormat[1];
+    }
+    else {
+      buffer = stream_.userBuffer[1];
+      channels = stream_.nUserChannels[1];
+      format = stream_.userFormat;
+    }
+
+    // Read samples from device in interleaved/non-interleaved format.
+    if ( stream_.deviceInterleaved[1] )
+      result = snd_pcm_readi( handle[1], buffer, stream_.bufferSize );
+    else {
+      void *bufs[channels];
+      size_t offset = stream_.bufferSize * formatBytes( format );
+      for ( int i=0; i<channels; i++ )
+        bufs[i] = (void *) (buffer + (i * offset));
+      result = snd_pcm_readn( handle[1], bufs, stream_.bufferSize );
+    }
+
+    if ( result < (int) stream_.bufferSize ) {
+      // Either an error or overrun occured.
+      if ( result == -EPIPE ) {
+        snd_pcm_state_t state = snd_pcm_state( handle[1] );
+        if ( state == SND_PCM_STATE_XRUN ) {
+          apiInfo->xrun[1] = true;
+          result = snd_pcm_prepare( handle[1] );
+          if ( result < 0 ) {
+            errorStream_ << "RtApiAlsa::callbackEvent: error preparing device after overrun, " << snd_strerror( result ) << ".";
+            errorText_ = errorStream_.str();
+          }
+        }
+        else {
+          errorStream_ << "RtApiAlsa::callbackEvent: error, current state is " << snd_pcm_state_name( state ) << ", " << snd_strerror( result ) << ".";
+          errorText_ = errorStream_.str();
+        }
+      }
+      else {
+        errorStream_ << "RtApiAlsa::callbackEvent: audio read error, " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+      }
+      error( RtAudioError::WARNING );
+      goto tryOutput;
+    }
+
+    // Do byte swapping if necessary.
+    if ( stream_.doByteSwap[1] )
+      byteSwapBuffer( buffer, stream_.bufferSize * channels, format );
+
+    // Do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[1] )
+      convertBuffer( stream_.userBuffer[1], stream_.deviceBuffer, stream_.convertInfo[1] );
+
+    // Check stream latency
+    result = snd_pcm_delay( handle[1], &frames );
+    if ( result == 0 && frames > 0 ) stream_.latency[1] = frames;
+  }
+
+ tryOutput:
+
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    // Setup parameters and do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[0] ) {
+      buffer = stream_.deviceBuffer;
+      convertBuffer( buffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+      channels = stream_.nDeviceChannels[0];
+      format = stream_.deviceFormat[0];
+    }
+    else {
+      buffer = stream_.userBuffer[0];
+      channels = stream_.nUserChannels[0];
+      format = stream_.userFormat;
+    }
+
+    // Do byte swapping if necessary.
+    if ( stream_.doByteSwap[0] )
+      byteSwapBuffer(buffer, stream_.bufferSize * channels, format);
+
+    // Write samples to device in interleaved/non-interleaved format.
+    if ( stream_.deviceInterleaved[0] )
+      result = snd_pcm_writei( handle[0], buffer, stream_.bufferSize );
+    else {
+      void *bufs[channels];
+      size_t offset = stream_.bufferSize * formatBytes( format );
+      for ( int i=0; i<channels; i++ )
+        bufs[i] = (void *) (buffer + (i * offset));
+      result = snd_pcm_writen( handle[0], bufs, stream_.bufferSize );
+    }
+
+    if ( result < (int) stream_.bufferSize ) {
+      // Either an error or underrun occured.
+      if ( result == -EPIPE ) {
+        snd_pcm_state_t state = snd_pcm_state( handle[0] );
+        if ( state == SND_PCM_STATE_XRUN ) {
+          apiInfo->xrun[0] = true;
+          result = snd_pcm_prepare( handle[0] );
+          if ( result < 0 ) {
+            errorStream_ << "RtApiAlsa::callbackEvent: error preparing device after underrun, " << snd_strerror( result ) << ".";
+            errorText_ = errorStream_.str();
+          }
+          else
+            errorText_ =  "RtApiAlsa::callbackEvent: audio write error, underrun.";
+        }
+        else {
+          errorStream_ << "RtApiAlsa::callbackEvent: error, current state is " << snd_pcm_state_name( state ) << ", " << snd_strerror( result ) << ".";
+          errorText_ = errorStream_.str();
+        }
+      }
+      else {
+        errorStream_ << "RtApiAlsa::callbackEvent: audio write error, " << snd_strerror( result ) << ".";
+        errorText_ = errorStream_.str();
+      }
+      error( RtAudioError::WARNING );
+      goto unlock;
+    }
+
+    // Check stream latency
+    result = snd_pcm_delay( handle[0], &frames );
+    if ( result == 0 && frames > 0 ) stream_.latency[0] = frames;
+  }
+
+ unlock:
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  RtApi::tickStreamTime();
+  if ( doStopStream == 1 ) this->stopStream();
+}
+
+static void *alsaCallbackHandler( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiAlsa *object = (RtApiAlsa *) info->object;
+  bool *isRunning = &info->isRunning;
+
+#ifdef SCHED_RR // Undefined with some OSes (eg: NetBSD 1.6.x with GNU Pthread)
+  if ( info->doRealtime ) {
+    pthread_t tID = pthread_self();	 // ID of this thread
+    sched_param prio = { info->priority }; // scheduling priority of thread
+    pthread_setschedparam( tID, SCHED_RR, &prio );
+  }
+#endif
+
+  while ( *isRunning == true ) {
+    pthread_testcancel();
+    object->callbackEvent();
+  }
+
+  pthread_exit( NULL );
+}
+
+//******************** End of __LINUX_ALSA__ *********************//
+#endif
+
+#if defined(__LINUX_PULSE__)
+
+// Code written by Peter Meerwald, pmeerw at pmeerw.net
+// and Tristan Matthews.
+
+#include <pulse/error.h>
+#include <pulse/simple.h>
+#include <cstdio>
+
+static const unsigned int SUPPORTED_SAMPLERATES[] = { 8000, 16000, 22050, 32000,
+                                                      44100, 48000, 96000, 0};
+
+struct rtaudio_pa_format_mapping_t {
+  RtAudioFormat rtaudio_format;
+  pa_sample_format_t pa_format;
+};
+
+static const rtaudio_pa_format_mapping_t supported_sampleformats[] = {
+  {RTAUDIO_SINT16, PA_SAMPLE_S16LE},
+  {RTAUDIO_SINT32, PA_SAMPLE_S32LE},
+  {RTAUDIO_FLOAT32, PA_SAMPLE_FLOAT32LE},
+  {0, PA_SAMPLE_INVALID}};
+
+struct PulseAudioHandle {
+  pa_simple *s_play;
+  pa_simple *s_rec;
+  pthread_t thread;
+  pthread_cond_t runnable_cv;
+  bool runnable;
+  PulseAudioHandle() : s_play(0), s_rec(0), runnable(false) { }
+};
+
+RtApiPulse::~RtApiPulse()
+{
+  if ( stream_.state != STREAM_CLOSED )
+    closeStream();
+}
+
+unsigned int RtApiPulse::getDeviceCount( void )
+{
+  return 1;
+}
+
+RtAudio::DeviceInfo RtApiPulse::getDeviceInfo( unsigned int /*device*/ )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = true;
+  info.name = "PulseAudio";
+  info.outputChannels = 2;
+  info.inputChannels = 2;
+  info.duplexChannels = 2;
+  info.isDefaultOutput = true;
+  info.isDefaultInput = true;
+
+  for ( const unsigned int *sr = SUPPORTED_SAMPLERATES; *sr; ++sr )
+    info.sampleRates.push_back( *sr );
+
+  info.preferredSampleRate = 48000;
+  info.nativeFormats = RTAUDIO_SINT16 | RTAUDIO_SINT32 | RTAUDIO_FLOAT32;
+
+  return info;
+}
+
+static void *pulseaudio_callback( void * user )
+{
+  CallbackInfo *cbi = static_cast<CallbackInfo *>( user );
+  RtApiPulse *context = static_cast<RtApiPulse *>( cbi->object );
+  volatile bool *isRunning = &cbi->isRunning;
+
+  while ( *isRunning ) {
+    pthread_testcancel();
+    context->callbackEvent();
+  }
+
+  pthread_exit( NULL );
+}
+
+void RtApiPulse::closeStream( void )
+{
+  PulseAudioHandle *pah = static_cast<PulseAudioHandle *>( stream_.apiHandle );
+
+  stream_.callbackInfo.isRunning = false;
+  if ( pah ) {
+    MUTEX_LOCK( &stream_.mutex );
+    if ( stream_.state == STREAM_STOPPED ) {
+      pah->runnable = true;
+      pthread_cond_signal( &pah->runnable_cv );
+    }
+    MUTEX_UNLOCK( &stream_.mutex );
+
+    pthread_join( pah->thread, 0 );
+    if ( pah->s_play ) {
+      pa_simple_flush( pah->s_play, NULL );
+      pa_simple_free( pah->s_play );
+    }
+    if ( pah->s_rec )
+      pa_simple_free( pah->s_rec );
+
+    pthread_cond_destroy( &pah->runnable_cv );
+    delete pah;
+    stream_.apiHandle = 0;
+  }
+
+  if ( stream_.userBuffer[0] ) {
+    free( stream_.userBuffer[0] );
+    stream_.userBuffer[0] = 0;
+  }
+  if ( stream_.userBuffer[1] ) {
+    free( stream_.userBuffer[1] );
+    stream_.userBuffer[1] = 0;
+  }
+
+  stream_.state = STREAM_CLOSED;
+  stream_.mode = UNINITIALIZED;
+}
+
+void RtApiPulse::callbackEvent( void )
+{
+  PulseAudioHandle *pah = static_cast<PulseAudioHandle *>( stream_.apiHandle );
+
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_LOCK( &stream_.mutex );
+    while ( !pah->runnable )
+      pthread_cond_wait( &pah->runnable_cv, &stream_.mutex );
+
+    if ( stream_.state != STREAM_RUNNING ) {
+      MUTEX_UNLOCK( &stream_.mutex );
+      return;
+    }
+    MUTEX_UNLOCK( &stream_.mutex );
+  }
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiPulse::callbackEvent(): the stream is closed ... "
+      "this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  RtAudioCallback callback = (RtAudioCallback) stream_.callbackInfo.callback;
+  double streamTime = getStreamTime();
+  RtAudioStreamStatus status = 0;
+  int doStopStream = callback( stream_.userBuffer[OUTPUT], stream_.userBuffer[INPUT],
+                               stream_.bufferSize, streamTime, status,
+                               stream_.callbackInfo.userData );
+
+  if ( doStopStream == 2 ) {
+    abortStream();
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+  void *pulse_in = stream_.doConvertBuffer[INPUT] ? stream_.deviceBuffer : stream_.userBuffer[INPUT];
+  void *pulse_out = stream_.doConvertBuffer[OUTPUT] ? stream_.deviceBuffer : stream_.userBuffer[OUTPUT];
+
+  if ( stream_.state != STREAM_RUNNING )
+    goto unlock;
+
+  int pa_error;
+  size_t bytes;
+  if (stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    if ( stream_.doConvertBuffer[OUTPUT] ) {
+        convertBuffer( stream_.deviceBuffer,
+                       stream_.userBuffer[OUTPUT],
+                       stream_.convertInfo[OUTPUT] );
+        bytes = stream_.nDeviceChannels[OUTPUT] * stream_.bufferSize *
+                formatBytes( stream_.deviceFormat[OUTPUT] );
+    } else
+        bytes = stream_.nUserChannels[OUTPUT] * stream_.bufferSize *
+                formatBytes( stream_.userFormat );
+
+    if ( pa_simple_write( pah->s_play, pulse_out, bytes, &pa_error ) < 0 ) {
+      errorStream_ << "RtApiPulse::callbackEvent: audio write error, " <<
+        pa_strerror( pa_error ) << ".";
+      errorText_ = errorStream_.str();
+      error( RtAudioError::WARNING );
+    }
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX) {
+    if ( stream_.doConvertBuffer[INPUT] )
+      bytes = stream_.nDeviceChannels[INPUT] * stream_.bufferSize *
+        formatBytes( stream_.deviceFormat[INPUT] );
+    else
+      bytes = stream_.nUserChannels[INPUT] * stream_.bufferSize *
+        formatBytes( stream_.userFormat );
+            
+    if ( pa_simple_read( pah->s_rec, pulse_in, bytes, &pa_error ) < 0 ) {
+      errorStream_ << "RtApiPulse::callbackEvent: audio read error, " <<
+        pa_strerror( pa_error ) << ".";
+      errorText_ = errorStream_.str();
+      error( RtAudioError::WARNING );
+    }
+    if ( stream_.doConvertBuffer[INPUT] ) {
+      convertBuffer( stream_.userBuffer[INPUT],
+                     stream_.deviceBuffer,
+                     stream_.convertInfo[INPUT] );
+    }
+  }
+
+ unlock:
+  MUTEX_UNLOCK( &stream_.mutex );
+  RtApi::tickStreamTime();
+
+  if ( doStopStream == 1 )
+    stopStream();
+}
+
+void RtApiPulse::startStream( void )
+{
+  PulseAudioHandle *pah = static_cast<PulseAudioHandle *>( stream_.apiHandle );
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiPulse::startStream(): the stream is not open!";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiPulse::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  stream_.state = STREAM_RUNNING;
+
+  pah->runnable = true;
+  pthread_cond_signal( &pah->runnable_cv );
+  MUTEX_UNLOCK( &stream_.mutex );
+}
+
+void RtApiPulse::stopStream( void )
+{
+  PulseAudioHandle *pah = static_cast<PulseAudioHandle *>( stream_.apiHandle );
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiPulse::stopStream(): the stream is not open!";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiPulse::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_LOCK( &stream_.mutex );
+
+  if ( pah && pah->s_play ) {
+    int pa_error;
+    if ( pa_simple_drain( pah->s_play, &pa_error ) < 0 ) {
+      errorStream_ << "RtApiPulse::stopStream: error draining output device, " <<
+        pa_strerror( pa_error ) << ".";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_UNLOCK( &stream_.mutex );
+}
+
+void RtApiPulse::abortStream( void )
+{
+  PulseAudioHandle *pah = static_cast<PulseAudioHandle*>( stream_.apiHandle );
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiPulse::abortStream(): the stream is not open!";
+    error( RtAudioError::INVALID_USE );
+    return;
+  }
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiPulse::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_LOCK( &stream_.mutex );
+
+  if ( pah && pah->s_play ) {
+    int pa_error;
+    if ( pa_simple_flush( pah->s_play, &pa_error ) < 0 ) {
+      errorStream_ << "RtApiPulse::abortStream: error flushing output device, " <<
+        pa_strerror( pa_error ) << ".";
+      errorText_ = errorStream_.str();
+      MUTEX_UNLOCK( &stream_.mutex );
+      error( RtAudioError::SYSTEM_ERROR );
+      return;
+    }
+  }
+
+  stream_.state = STREAM_STOPPED;
+  MUTEX_UNLOCK( &stream_.mutex );
+}
+
+bool RtApiPulse::probeDeviceOpen( unsigned int device, StreamMode mode,
+                                  unsigned int channels, unsigned int firstChannel,
+                                  unsigned int sampleRate, RtAudioFormat format,
+                                  unsigned int *bufferSize, RtAudio::StreamOptions *options )
+{
+  PulseAudioHandle *pah = 0;
+  unsigned long bufferBytes = 0;
+  pa_sample_spec ss;
+
+  if ( device != 0 ) return false;
+  if ( mode != INPUT && mode != OUTPUT ) return false;
+  if ( channels != 1 && channels != 2 ) {
+    errorText_ = "RtApiPulse::probeDeviceOpen: unsupported number of channels.";
+    return false;
+  }
+  ss.channels = channels;
+
+  if ( firstChannel != 0 ) return false;
+
+  bool sr_found = false;
+  for ( const unsigned int *sr = SUPPORTED_SAMPLERATES; *sr; ++sr ) {
+    if ( sampleRate == *sr ) {
+      sr_found = true;
+      stream_.sampleRate = sampleRate;
+      ss.rate = sampleRate;
+      break;
+    }
+  }
+  if ( !sr_found ) {
+    errorText_ = "RtApiPulse::probeDeviceOpen: unsupported sample rate.";
+    return false;
+  }
+
+  bool sf_found = 0;
+  for ( const rtaudio_pa_format_mapping_t *sf = supported_sampleformats;
+        sf->rtaudio_format && sf->pa_format != PA_SAMPLE_INVALID; ++sf ) {
+    if ( format == sf->rtaudio_format ) {
+      sf_found = true;
+      stream_.userFormat = sf->rtaudio_format;
+      stream_.deviceFormat[mode] = stream_.userFormat;
+      ss.format = sf->pa_format;
+      break;
+    }
+  }
+  if ( !sf_found ) { // Use internal data format conversion.
+    stream_.userFormat = format;
+    stream_.deviceFormat[mode] = RTAUDIO_FLOAT32;
+    ss.format = PA_SAMPLE_FLOAT32LE;
+  }
+
+  // Set other stream parameters.
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED ) stream_.userInterleaved = false;
+  else stream_.userInterleaved = true;
+  stream_.deviceInterleaved[mode] = true;
+  stream_.nBuffers = 1;
+  stream_.doByteSwap[mode] = false;
+  stream_.nUserChannels[mode] = channels;
+  stream_.nDeviceChannels[mode] = channels + firstChannel;
+  stream_.channelOffset[mode] = 0;
+  std::string streamName = "RtAudio";
+
+  // Set flags for buffer conversion.
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.nUserChannels[mode] < stream_.nDeviceChannels[mode] )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate necessary internal buffers.
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiPulse::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+  stream_.bufferSize = *bufferSize;
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( mode == INPUT ) {
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+        if ( bufferBytes <= bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiPulse::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  stream_.device[mode] = device;
+
+  // Setup the buffer conversion information structure.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, firstChannel );
+
+  if ( !stream_.apiHandle ) {
+    PulseAudioHandle *pah = new PulseAudioHandle;
+    if ( !pah ) {
+      errorText_ = "RtApiPulse::probeDeviceOpen: error allocating memory for handle.";
+      goto error;
+    }
+
+    stream_.apiHandle = pah;
+    if ( pthread_cond_init( &pah->runnable_cv, NULL ) != 0 ) {
+      errorText_ = "RtApiPulse::probeDeviceOpen: error creating condition variable.";
+      goto error;
+    }
+  }
+  pah = static_cast<PulseAudioHandle *>( stream_.apiHandle );
+
+  int error;
+  if ( options && !options->streamName.empty() ) streamName = options->streamName;
+  switch ( mode ) {
+  case INPUT:
+    pa_buffer_attr buffer_attr;
+    buffer_attr.fragsize = bufferBytes;
+    buffer_attr.maxlength = -1;
+
+    pah->s_rec = pa_simple_new( NULL, streamName.c_str(), PA_STREAM_RECORD, NULL, "Record", &ss, NULL, &buffer_attr, &error );
+    if ( !pah->s_rec ) {
+      errorText_ = "RtApiPulse::probeDeviceOpen: error connecting input to PulseAudio server.";
+      goto error;
+    }
+    break;
+  case OUTPUT:
+    pah->s_play = pa_simple_new( NULL, streamName.c_str(), PA_STREAM_PLAYBACK, NULL, "Playback", &ss, NULL, NULL, &error );
+    if ( !pah->s_play ) {
+      errorText_ = "RtApiPulse::probeDeviceOpen: error connecting output to PulseAudio server.";
+      goto error;
+    }
+    break;
+  default:
+    goto error;
+  }
+
+  if ( stream_.mode == UNINITIALIZED )
+    stream_.mode = mode;
+  else if ( stream_.mode == mode )
+    goto error;
+  else
+    stream_.mode = DUPLEX;
+
+  if ( !stream_.callbackInfo.isRunning ) {
+    stream_.callbackInfo.object = this;
+    stream_.callbackInfo.isRunning = true;
+    if ( pthread_create( &pah->thread, NULL, pulseaudio_callback, (void *)&stream_.callbackInfo) != 0 ) {
+      errorText_ = "RtApiPulse::probeDeviceOpen: error creating thread.";
+      goto error;
+    }
+  }
+
+  stream_.state = STREAM_STOPPED;
+  return true;
+ 
+ error:
+  if ( pah && stream_.callbackInfo.isRunning ) {
+    pthread_cond_destroy( &pah->runnable_cv );
+    delete pah;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  return FAILURE;
+}
+
+//******************** End of __LINUX_PULSE__ *********************//
+#endif
+
+#if defined(__LINUX_OSS__)
+
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/soundcard.h>
+#include <errno.h>
+#include <math.h>
+
+static void *ossCallbackHandler(void * ptr);
+
+// A structure to hold various information related to the OSS API
+// implementation.
+struct OssHandle {
+  int id[2];    // device ids
+  bool xrun[2];
+  bool triggered;
+  pthread_cond_t runnable;
+
+  OssHandle()
+    :triggered(false) { id[0] = 0; id[1] = 0; xrun[0] = false; xrun[1] = false; }
+};
+
+RtApiOss :: RtApiOss()
+{
+  // Nothing to do here.
+}
+
+RtApiOss :: ~RtApiOss()
+{
+  if ( stream_.state != STREAM_CLOSED ) closeStream();
+}
+
+unsigned int RtApiOss :: getDeviceCount( void )
+{
+  int mixerfd = open( "/dev/mixer", O_RDWR, 0 );
+  if ( mixerfd == -1 ) {
+    errorText_ = "RtApiOss::getDeviceCount: error opening '/dev/mixer'.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  oss_sysinfo sysinfo;
+  if ( ioctl( mixerfd, SNDCTL_SYSINFO, &sysinfo ) == -1 ) {
+    close( mixerfd );
+    errorText_ = "RtApiOss::getDeviceCount: error getting sysinfo, OSS version >= 4.0 is required.";
+    error( RtAudioError::WARNING );
+    return 0;
+  }
+
+  close( mixerfd );
+  return sysinfo.numaudios;
+}
+
+RtAudio::DeviceInfo RtApiOss :: getDeviceInfo( unsigned int device )
+{
+  RtAudio::DeviceInfo info;
+  info.probed = false;
+
+  int mixerfd = open( "/dev/mixer", O_RDWR, 0 );
+  if ( mixerfd == -1 ) {
+    errorText_ = "RtApiOss::getDeviceInfo: error opening '/dev/mixer'.";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  oss_sysinfo sysinfo;
+  int result = ioctl( mixerfd, SNDCTL_SYSINFO, &sysinfo );
+  if ( result == -1 ) {
+    close( mixerfd );
+    errorText_ = "RtApiOss::getDeviceInfo: error getting sysinfo, OSS version >= 4.0 is required.";
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  unsigned nDevices = sysinfo.numaudios;
+  if ( nDevices == 0 ) {
+    close( mixerfd );
+    errorText_ = "RtApiOss::getDeviceInfo: no devices found!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  if ( device >= nDevices ) {
+    close( mixerfd );
+    errorText_ = "RtApiOss::getDeviceInfo: device ID is invalid!";
+    error( RtAudioError::INVALID_USE );
+    return info;
+  }
+
+  oss_audioinfo ainfo;
+  ainfo.dev = device;
+  result = ioctl( mixerfd, SNDCTL_AUDIOINFO, &ainfo );
+  close( mixerfd );
+  if ( result == -1 ) {
+    errorStream_ << "RtApiOss::getDeviceInfo: error getting device (" << ainfo.name << ") info.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Probe channels
+  if ( ainfo.caps & PCM_CAP_OUTPUT ) info.outputChannels = ainfo.max_channels;
+  if ( ainfo.caps & PCM_CAP_INPUT ) info.inputChannels = ainfo.max_channels;
+  if ( ainfo.caps & PCM_CAP_DUPLEX ) {
+    if ( info.outputChannels > 0 && info.inputChannels > 0 && ainfo.caps & PCM_CAP_DUPLEX )
+      info.duplexChannels = (info.outputChannels > info.inputChannels) ? info.inputChannels : info.outputChannels;
+  }
+
+  // Probe data formats ... do for input
+  unsigned long mask = ainfo.iformats;
+  if ( mask & AFMT_S16_LE || mask & AFMT_S16_BE )
+    info.nativeFormats |= RTAUDIO_SINT16;
+  if ( mask & AFMT_S8 )
+    info.nativeFormats |= RTAUDIO_SINT8;
+  if ( mask & AFMT_S32_LE || mask & AFMT_S32_BE )
+    info.nativeFormats |= RTAUDIO_SINT32;
+  if ( mask & AFMT_FLOAT )
+    info.nativeFormats |= RTAUDIO_FLOAT32;
+  if ( mask & AFMT_S24_LE || mask & AFMT_S24_BE )
+    info.nativeFormats |= RTAUDIO_SINT24;
+
+  // Check that we have at least one supported format
+  if ( info.nativeFormats == 0 ) {
+    errorStream_ << "RtApiOss::getDeviceInfo: device (" << ainfo.name << ") data format not supported by RtAudio.";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+    return info;
+  }
+
+  // Probe the supported sample rates.
+  info.sampleRates.clear();
+  if ( ainfo.nrates ) {
+    for ( unsigned int i=0; i<ainfo.nrates; i++ ) {
+      for ( unsigned int k=0; k<MAX_SAMPLE_RATES; k++ ) {
+        if ( ainfo.rates[i] == SAMPLE_RATES[k] ) {
+          info.sampleRates.push_back( SAMPLE_RATES[k] );
+
+          if ( !info.preferredSampleRate || ( SAMPLE_RATES[k] <= 48000 && SAMPLE_RATES[k] > info.preferredSampleRate ) )
+            info.preferredSampleRate = SAMPLE_RATES[k];
+
+          break;
+        }
+      }
+    }
+  }
+  else {
+    // Check min and max rate values;
+    for ( unsigned int k=0; k<MAX_SAMPLE_RATES; k++ ) {
+      if ( ainfo.min_rate <= (int) SAMPLE_RATES[k] && ainfo.max_rate >= (int) SAMPLE_RATES[k] ) {
+        info.sampleRates.push_back( SAMPLE_RATES[k] );
+
+        if ( !info.preferredSampleRate || ( SAMPLE_RATES[k] <= 48000 && SAMPLE_RATES[k] > info.preferredSampleRate ) )
+          info.preferredSampleRate = SAMPLE_RATES[k];
+      }
+    }
+  }
+
+  if ( info.sampleRates.size() == 0 ) {
+    errorStream_ << "RtApiOss::getDeviceInfo: no supported sample rates found for device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    error( RtAudioError::WARNING );
+  }
+  else {
+    info.probed = true;
+    info.name = ainfo.name;
+  }
+
+  return info;
+}
+
+
+bool RtApiOss :: probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                                  unsigned int firstChannel, unsigned int sampleRate,
+                                  RtAudioFormat format, unsigned int *bufferSize,
+                                  RtAudio::StreamOptions *options )
+{
+  int mixerfd = open( "/dev/mixer", O_RDWR, 0 );
+  if ( mixerfd == -1 ) {
+    errorText_ = "RtApiOss::probeDeviceOpen: error opening '/dev/mixer'.";
+    return FAILURE;
+  }
+
+  oss_sysinfo sysinfo;
+  int result = ioctl( mixerfd, SNDCTL_SYSINFO, &sysinfo );
+  if ( result == -1 ) {
+    close( mixerfd );
+    errorText_ = "RtApiOss::probeDeviceOpen: error getting sysinfo, OSS version >= 4.0 is required.";
+    return FAILURE;
+  }
+
+  unsigned nDevices = sysinfo.numaudios;
+  if ( nDevices == 0 ) {
+    // This should not happen because a check is made before this function is called.
+    close( mixerfd );
+    errorText_ = "RtApiOss::probeDeviceOpen: no devices found!";
+    return FAILURE;
+  }
+
+  if ( device >= nDevices ) {
+    // This should not happen because a check is made before this function is called.
+    close( mixerfd );
+    errorText_ = "RtApiOss::probeDeviceOpen: device ID is invalid!";
+    return FAILURE;
+  }
+
+  oss_audioinfo ainfo;
+  ainfo.dev = device;
+  result = ioctl( mixerfd, SNDCTL_AUDIOINFO, &ainfo );
+  close( mixerfd );
+  if ( result == -1 ) {
+    errorStream_ << "RtApiOss::getDeviceInfo: error getting device (" << ainfo.name << ") info.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Check if device supports input or output
+  if ( ( mode == OUTPUT && !( ainfo.caps & PCM_CAP_OUTPUT ) ) ||
+       ( mode == INPUT && !( ainfo.caps & PCM_CAP_INPUT ) ) ) {
+    if ( mode == OUTPUT )
+      errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") does not support output.";
+    else
+      errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") does not support input.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  int flags = 0;
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  if ( mode == OUTPUT )
+    flags |= O_WRONLY;
+  else { // mode == INPUT
+    if (stream_.mode == OUTPUT && stream_.device[0] == device) {
+      // We just set the same device for playback ... close and reopen for duplex (OSS only).
+      close( handle->id[0] );
+      handle->id[0] = 0;
+      if ( !( ainfo.caps & PCM_CAP_DUPLEX ) ) {
+        errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") does not support duplex mode.";
+        errorText_ = errorStream_.str();
+        return FAILURE;
+      }
+      // Check that the number previously set channels is the same.
+      if ( stream_.nUserChannels[0] != channels ) {
+        errorStream_ << "RtApiOss::probeDeviceOpen: input/output channels must be equal for OSS duplex device (" << ainfo.name << ").";
+        errorText_ = errorStream_.str();
+        return FAILURE;
+      }
+      flags |= O_RDWR;
+    }
+    else
+      flags |= O_RDONLY;
+  }
+
+  // Set exclusive access if specified.
+  if ( options && options->flags & RTAUDIO_HOG_DEVICE ) flags |= O_EXCL;
+
+  // Try to open the device.
+  int fd;
+  fd = open( ainfo.devnode, flags, 0 );
+  if ( fd == -1 ) {
+    if ( errno == EBUSY )
+      errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") is busy.";
+    else
+      errorStream_ << "RtApiOss::probeDeviceOpen: error opening device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // For duplex operation, specifically set this mode (this doesn't seem to work).
+  /*
+    if ( flags | O_RDWR ) {
+    result = ioctl( fd, SNDCTL_DSP_SETDUPLEX, NULL );
+    if ( result == -1) {
+    errorStream_ << "RtApiOss::probeDeviceOpen: error setting duplex mode for device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+    }
+    }
+  */
+
+  // Check the device channel support.
+  stream_.nUserChannels[mode] = channels;
+  if ( ainfo.max_channels < (int)(channels + firstChannel) ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: the device (" << ainfo.name << ") does not support requested channel parameters.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Set the number of channels.
+  int deviceChannels = channels + firstChannel;
+  result = ioctl( fd, SNDCTL_DSP_CHANNELS, &deviceChannels );
+  if ( result == -1 || deviceChannels < (int)(channels + firstChannel) ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: error setting channel parameters on device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  stream_.nDeviceChannels[mode] = deviceChannels;
+
+  // Get the data format mask
+  int mask;
+  result = ioctl( fd, SNDCTL_DSP_GETFMTS, &mask );
+  if ( result == -1 ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: error getting device (" << ainfo.name << ") data formats.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Determine how to set the device format.
+  stream_.userFormat = format;
+  int deviceFormat = -1;
+  stream_.doByteSwap[mode] = false;
+  if ( format == RTAUDIO_SINT8 ) {
+    if ( mask & AFMT_S8 ) {
+      deviceFormat = AFMT_S8;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+    }
+  }
+  else if ( format == RTAUDIO_SINT16 ) {
+    if ( mask & AFMT_S16_NE ) {
+      deviceFormat = AFMT_S16_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+    }
+    else if ( mask & AFMT_S16_OE ) {
+      deviceFormat = AFMT_S16_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+      stream_.doByteSwap[mode] = true;
+    }
+  }
+  else if ( format == RTAUDIO_SINT24 ) {
+    if ( mask & AFMT_S24_NE ) {
+      deviceFormat = AFMT_S24_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+    }
+    else if ( mask & AFMT_S24_OE ) {
+      deviceFormat = AFMT_S24_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+      stream_.doByteSwap[mode] = true;
+    }
+  }
+  else if ( format == RTAUDIO_SINT32 ) {
+    if ( mask & AFMT_S32_NE ) {
+      deviceFormat = AFMT_S32_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+    }
+    else if ( mask & AFMT_S32_OE ) {
+      deviceFormat = AFMT_S32_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+      stream_.doByteSwap[mode] = true;
+    }
+  }
+
+  if ( deviceFormat == -1 ) {
+    // The user requested format is not natively supported by the device.
+    if ( mask & AFMT_S16_NE ) {
+      deviceFormat = AFMT_S16_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+    }
+    else if ( mask & AFMT_S32_NE ) {
+      deviceFormat = AFMT_S32_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+    }
+    else if ( mask & AFMT_S24_NE ) {
+      deviceFormat = AFMT_S24_NE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+    }
+    else if ( mask & AFMT_S16_OE ) {
+      deviceFormat = AFMT_S16_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT16;
+      stream_.doByteSwap[mode] = true;
+    }
+    else if ( mask & AFMT_S32_OE ) {
+      deviceFormat = AFMT_S32_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT32;
+      stream_.doByteSwap[mode] = true;
+    }
+    else if ( mask & AFMT_S24_OE ) {
+      deviceFormat = AFMT_S24_OE;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT24;
+      stream_.doByteSwap[mode] = true;
+    }
+    else if ( mask & AFMT_S8) {
+      deviceFormat = AFMT_S8;
+      stream_.deviceFormat[mode] = RTAUDIO_SINT8;
+    }
+  }
+
+  if ( stream_.deviceFormat[mode] == 0 ) {
+    // This really shouldn't happen ...
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") data format not supported by RtAudio.";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Set the data format.
+  int temp = deviceFormat;
+  result = ioctl( fd, SNDCTL_DSP_SETFMT, &deviceFormat );
+  if ( result == -1 || deviceFormat != temp ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: error setting data format on device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Attempt to set the buffer size.  According to OSS, the minimum
+  // number of buffers is two.  The supposed minimum buffer size is 16
+  // bytes, so that will be our lower bound.  The argument to this
+  // call is in the form 0xMMMMSSSS (hex), where the buffer size (in
+  // bytes) is given as 2^SSSS and the number of buffers as 2^MMMM.
+  // We'll check the actual value used near the end of the setup
+  // procedure.
+  int ossBufferBytes = *bufferSize * formatBytes( stream_.deviceFormat[mode] ) * deviceChannels;
+  if ( ossBufferBytes < 16 ) ossBufferBytes = 16;
+  int buffers = 0;
+  if ( options ) buffers = options->numberOfBuffers;
+  if ( options && options->flags & RTAUDIO_MINIMIZE_LATENCY ) buffers = 2;
+  if ( buffers < 2 ) buffers = 3;
+  temp = ((int) buffers << 16) + (int)( log10( (double)ossBufferBytes ) / log10( 2.0 ) );
+  result = ioctl( fd, SNDCTL_DSP_SETFRAGMENT, &temp );
+  if ( result == -1 ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: error setting buffer size on device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  stream_.nBuffers = buffers;
+
+  // Save buffer size (in sample frames).
+  *bufferSize = ossBufferBytes / ( formatBytes(stream_.deviceFormat[mode]) * deviceChannels );
+  stream_.bufferSize = *bufferSize;
+
+  // Set the sample rate.
+  int srate = sampleRate;
+  result = ioctl( fd, SNDCTL_DSP_SPEED, &srate );
+  if ( result == -1 ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: error setting sample rate (" << sampleRate << ") on device (" << ainfo.name << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+
+  // Verify the sample rate setup worked.
+  if ( abs( srate - sampleRate ) > 100 ) {
+    close( fd );
+    errorStream_ << "RtApiOss::probeDeviceOpen: device (" << ainfo.name << ") does not support sample rate (" << sampleRate << ").";
+    errorText_ = errorStream_.str();
+    return FAILURE;
+  }
+  stream_.sampleRate = sampleRate;
+
+  if ( mode == INPUT && stream_.mode == OUTPUT && stream_.device[0] == device) {
+    // We're doing duplex setup here.
+    stream_.deviceFormat[0] = stream_.deviceFormat[1];
+    stream_.nDeviceChannels[0] = deviceChannels;
+  }
+
+  // Set interleaving parameters.
+  stream_.userInterleaved = true;
+  stream_.deviceInterleaved[mode] =  true;
+  if ( options && options->flags & RTAUDIO_NONINTERLEAVED )
+    stream_.userInterleaved = false;
+
+  // Set flags for buffer conversion
+  stream_.doConvertBuffer[mode] = false;
+  if ( stream_.userFormat != stream_.deviceFormat[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.nUserChannels[mode] < stream_.nDeviceChannels[mode] )
+    stream_.doConvertBuffer[mode] = true;
+  if ( stream_.userInterleaved != stream_.deviceInterleaved[mode] &&
+       stream_.nUserChannels[mode] > 1 )
+    stream_.doConvertBuffer[mode] = true;
+
+  // Allocate the stream handles if necessary and then save.
+  if ( stream_.apiHandle == 0 ) {
+    try {
+      handle = new OssHandle;
+    }
+    catch ( std::bad_alloc& ) {
+      errorText_ = "RtApiOss::probeDeviceOpen: error allocating OssHandle memory.";
+      goto error;
+    }
+
+    if ( pthread_cond_init( &handle->runnable, NULL ) ) {
+      errorText_ = "RtApiOss::probeDeviceOpen: error initializing pthread condition variable.";
+      goto error;
+    }
+
+    stream_.apiHandle = (void *) handle;
+  }
+  else {
+    handle = (OssHandle *) stream_.apiHandle;
+  }
+  handle->id[mode] = fd;
+
+  // Allocate necessary internal buffers.
+  unsigned long bufferBytes;
+  bufferBytes = stream_.nUserChannels[mode] * *bufferSize * formatBytes( stream_.userFormat );
+  stream_.userBuffer[mode] = (char *) calloc( bufferBytes, 1 );
+  if ( stream_.userBuffer[mode] == NULL ) {
+    errorText_ = "RtApiOss::probeDeviceOpen: error allocating user buffer memory.";
+    goto error;
+  }
+
+  if ( stream_.doConvertBuffer[mode] ) {
+
+    bool makeBuffer = true;
+    bufferBytes = stream_.nDeviceChannels[mode] * formatBytes( stream_.deviceFormat[mode] );
+    if ( mode == INPUT ) {
+      if ( stream_.mode == OUTPUT && stream_.deviceBuffer ) {
+        unsigned long bytesOut = stream_.nDeviceChannels[0] * formatBytes( stream_.deviceFormat[0] );
+        if ( bufferBytes <= bytesOut ) makeBuffer = false;
+      }
+    }
+
+    if ( makeBuffer ) {
+      bufferBytes *= *bufferSize;
+      if ( stream_.deviceBuffer ) free( stream_.deviceBuffer );
+      stream_.deviceBuffer = (char *) calloc( bufferBytes, 1 );
+      if ( stream_.deviceBuffer == NULL ) {
+        errorText_ = "RtApiOss::probeDeviceOpen: error allocating device buffer memory.";
+        goto error;
+      }
+    }
+  }
+
+  stream_.device[mode] = device;
+  stream_.state = STREAM_STOPPED;
+
+  // Setup the buffer conversion information structure.
+  if ( stream_.doConvertBuffer[mode] ) setConvertInfo( mode, firstChannel );
+
+  // Setup thread if necessary.
+  if ( stream_.mode == OUTPUT && mode == INPUT ) {
+    // We had already set up an output stream.
+    stream_.mode = DUPLEX;
+    if ( stream_.device[0] == device ) handle->id[0] = fd;
+  }
+  else {
+    stream_.mode = mode;
+
+    // Setup callback thread.
+    stream_.callbackInfo.object = (void *) this;
+
+    // Set the thread attributes for joinable and realtime scheduling
+    // priority.  The higher priority will only take affect if the
+    // program is run as root or suid.
+    pthread_attr_t attr;
+    pthread_attr_init( &attr );
+    pthread_attr_setdetachstate( &attr, PTHREAD_CREATE_JOINABLE );
+#ifdef SCHED_RR // Undefined with some OSes (eg: NetBSD 1.6.x with GNU Pthread)
+    if ( options && options->flags & RTAUDIO_SCHEDULE_REALTIME ) {
+      struct sched_param param;
+      int priority = options->priority;
+      int min = sched_get_priority_min( SCHED_RR );
+      int max = sched_get_priority_max( SCHED_RR );
+      if ( priority < min ) priority = min;
+      else if ( priority > max ) priority = max;
+      param.sched_priority = priority;
+      pthread_attr_setschedparam( &attr, &param );
+      pthread_attr_setschedpolicy( &attr, SCHED_RR );
+    }
+    else
+      pthread_attr_setschedpolicy( &attr, SCHED_OTHER );
+#else
+    pthread_attr_setschedpolicy( &attr, SCHED_OTHER );
+#endif
+
+    stream_.callbackInfo.isRunning = true;
+    result = pthread_create( &stream_.callbackInfo.thread, &attr, ossCallbackHandler, &stream_.callbackInfo );
+    pthread_attr_destroy( &attr );
+    if ( result ) {
+      stream_.callbackInfo.isRunning = false;
+      errorText_ = "RtApiOss::error creating callback thread!";
+      goto error;
+    }
+  }
+
+  return SUCCESS;
+
+ error:
+  if ( handle ) {
+    pthread_cond_destroy( &handle->runnable );
+    if ( handle->id[0] ) close( handle->id[0] );
+    if ( handle->id[1] ) close( handle->id[1] );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  return FAILURE;
+}
+
+void RtApiOss :: closeStream()
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiOss::closeStream(): no open stream to close!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  stream_.callbackInfo.isRunning = false;
+  MUTEX_LOCK( &stream_.mutex );
+  if ( stream_.state == STREAM_STOPPED )
+    pthread_cond_signal( &handle->runnable );
+  MUTEX_UNLOCK( &stream_.mutex );
+  pthread_join( stream_.callbackInfo.thread, NULL );
+
+  if ( stream_.state == STREAM_RUNNING ) {
+    if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX )
+      ioctl( handle->id[0], SNDCTL_DSP_HALT, 0 );
+    else
+      ioctl( handle->id[1], SNDCTL_DSP_HALT, 0 );
+    stream_.state = STREAM_STOPPED;
+  }
+
+  if ( handle ) {
+    pthread_cond_destroy( &handle->runnable );
+    if ( handle->id[0] ) close( handle->id[0] );
+    if ( handle->id[1] ) close( handle->id[1] );
+    delete handle;
+    stream_.apiHandle = 0;
+  }
+
+  for ( int i=0; i<2; i++ ) {
+    if ( stream_.userBuffer[i] ) {
+      free( stream_.userBuffer[i] );
+      stream_.userBuffer[i] = 0;
+    }
+  }
+
+  if ( stream_.deviceBuffer ) {
+    free( stream_.deviceBuffer );
+    stream_.deviceBuffer = 0;
+  }
+
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+}
+
+void RtApiOss :: startStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_RUNNING ) {
+    errorText_ = "RtApiOss::startStream(): the stream is already running!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  stream_.state = STREAM_RUNNING;
+
+  // No need to do anything else here ... OSS automatically starts
+  // when fed samples.
+
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  pthread_cond_signal( &handle->runnable );
+}
+
+void RtApiOss :: stopStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiOss::stopStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  // The state might change while waiting on a mutex.
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_UNLOCK( &stream_.mutex );
+    return;
+  }
+
+  int result = 0;
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    // Flush the output with zeros a few times.
+    char *buffer;
+    int samples;
+    RtAudioFormat format;
+
+    if ( stream_.doConvertBuffer[0] ) {
+      buffer = stream_.deviceBuffer;
+      samples = stream_.bufferSize * stream_.nDeviceChannels[0];
+      format = stream_.deviceFormat[0];
+    }
+    else {
+      buffer = stream_.userBuffer[0];
+      samples = stream_.bufferSize * stream_.nUserChannels[0];
+      format = stream_.userFormat;
+    }
+
+    memset( buffer, 0, samples * formatBytes(format) );
+    for ( unsigned int i=0; i<stream_.nBuffers+1; i++ ) {
+      result = write( handle->id[0], buffer, samples * formatBytes(format) );
+      if ( result == -1 ) {
+        errorText_ = "RtApiOss::stopStream: audio write error.";
+        error( RtAudioError::WARNING );
+      }
+    }
+
+    result = ioctl( handle->id[0], SNDCTL_DSP_HALT, 0 );
+    if ( result == -1 ) {
+      errorStream_ << "RtApiOss::stopStream: system error stopping callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+    handle->triggered = false;
+  }
+
+  if ( stream_.mode == INPUT || ( stream_.mode == DUPLEX && handle->id[0] != handle->id[1] ) ) {
+    result = ioctl( handle->id[1], SNDCTL_DSP_HALT, 0 );
+    if ( result == -1 ) {
+      errorStream_ << "RtApiOss::stopStream: system error stopping input callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+ unlock:
+  stream_.state = STREAM_STOPPED;
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( result != -1 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiOss :: abortStream()
+{
+  verifyStream();
+  if ( stream_.state == STREAM_STOPPED ) {
+    errorText_ = "RtApiOss::abortStream(): the stream is already stopped!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  // The state might change while waiting on a mutex.
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_UNLOCK( &stream_.mutex );
+    return;
+  }
+
+  int result = 0;
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+    result = ioctl( handle->id[0], SNDCTL_DSP_HALT, 0 );
+    if ( result == -1 ) {
+      errorStream_ << "RtApiOss::abortStream: system error stopping callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+    handle->triggered = false;
+  }
+
+  if ( stream_.mode == INPUT || ( stream_.mode == DUPLEX && handle->id[0] != handle->id[1] ) ) {
+    result = ioctl( handle->id[1], SNDCTL_DSP_HALT, 0 );
+    if ( result == -1 ) {
+      errorStream_ << "RtApiOss::abortStream: system error stopping input callback procedure on device (" << stream_.device[0] << ").";
+      errorText_ = errorStream_.str();
+      goto unlock;
+    }
+  }
+
+ unlock:
+  stream_.state = STREAM_STOPPED;
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  if ( result != -1 ) return;
+  error( RtAudioError::SYSTEM_ERROR );
+}
+
+void RtApiOss :: callbackEvent()
+{
+  OssHandle *handle = (OssHandle *) stream_.apiHandle;
+  if ( stream_.state == STREAM_STOPPED ) {
+    MUTEX_LOCK( &stream_.mutex );
+    pthread_cond_wait( &handle->runnable, &stream_.mutex );
+    if ( stream_.state != STREAM_RUNNING ) {
+      MUTEX_UNLOCK( &stream_.mutex );
+      return;
+    }
+    MUTEX_UNLOCK( &stream_.mutex );
+  }
+
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApiOss::callbackEvent(): the stream is closed ... this shouldn't happen!";
+    error( RtAudioError::WARNING );
+    return;
+  }
+
+  // Invoke user callback to get fresh output data.
+  int doStopStream = 0;
+  RtAudioCallback callback = (RtAudioCallback) stream_.callbackInfo.callback;
+  double streamTime = getStreamTime();
+  RtAudioStreamStatus status = 0;
+  if ( stream_.mode != INPUT && handle->xrun[0] == true ) {
+    status |= RTAUDIO_OUTPUT_UNDERFLOW;
+    handle->xrun[0] = false;
+  }
+  if ( stream_.mode != OUTPUT && handle->xrun[1] == true ) {
+    status |= RTAUDIO_INPUT_OVERFLOW;
+    handle->xrun[1] = false;
+  }
+  doStopStream = callback( stream_.userBuffer[0], stream_.userBuffer[1],
+                           stream_.bufferSize, streamTime, status, stream_.callbackInfo.userData );
+  if ( doStopStream == 2 ) {
+    this->abortStream();
+    return;
+  }
+
+  MUTEX_LOCK( &stream_.mutex );
+
+  // The state might change while waiting on a mutex.
+  if ( stream_.state == STREAM_STOPPED ) goto unlock;
+
+  int result;
+  char *buffer;
+  int samples;
+  RtAudioFormat format;
+
+  if ( stream_.mode == OUTPUT || stream_.mode == DUPLEX ) {
+
+    // Setup parameters and do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[0] ) {
+      buffer = stream_.deviceBuffer;
+      convertBuffer( buffer, stream_.userBuffer[0], stream_.convertInfo[0] );
+      samples = stream_.bufferSize * stream_.nDeviceChannels[0];
+      format = stream_.deviceFormat[0];
+    }
+    else {
+      buffer = stream_.userBuffer[0];
+      samples = stream_.bufferSize * stream_.nUserChannels[0];
+      format = stream_.userFormat;
+    }
+
+    // Do byte swapping if necessary.
+    if ( stream_.doByteSwap[0] )
+      byteSwapBuffer( buffer, samples, format );
+
+    if ( stream_.mode == DUPLEX && handle->triggered == false ) {
+      int trig = 0;
+      ioctl( handle->id[0], SNDCTL_DSP_SETTRIGGER, &trig );
+      result = write( handle->id[0], buffer, samples * formatBytes(format) );
+      trig = PCM_ENABLE_INPUT|PCM_ENABLE_OUTPUT;
+      ioctl( handle->id[0], SNDCTL_DSP_SETTRIGGER, &trig );
+      handle->triggered = true;
+    }
+    else
+      // Write samples to device.
+      result = write( handle->id[0], buffer, samples * formatBytes(format) );
+
+    if ( result == -1 ) {
+      // We'll assume this is an underrun, though there isn't a
+      // specific means for determining that.
+      handle->xrun[0] = true;
+      errorText_ = "RtApiOss::callbackEvent: audio write error.";
+      error( RtAudioError::WARNING );
+      // Continue on to input section.
+    }
+  }
+
+  if ( stream_.mode == INPUT || stream_.mode == DUPLEX ) {
+
+    // Setup parameters.
+    if ( stream_.doConvertBuffer[1] ) {
+      buffer = stream_.deviceBuffer;
+      samples = stream_.bufferSize * stream_.nDeviceChannels[1];
+      format = stream_.deviceFormat[1];
+    }
+    else {
+      buffer = stream_.userBuffer[1];
+      samples = stream_.bufferSize * stream_.nUserChannels[1];
+      format = stream_.userFormat;
+    }
+
+    // Read samples from device.
+    result = read( handle->id[1], buffer, samples * formatBytes(format) );
+
+    if ( result == -1 ) {
+      // We'll assume this is an overrun, though there isn't a
+      // specific means for determining that.
+      handle->xrun[1] = true;
+      errorText_ = "RtApiOss::callbackEvent: audio read error.";
+      error( RtAudioError::WARNING );
+      goto unlock;
+    }
+
+    // Do byte swapping if necessary.
+    if ( stream_.doByteSwap[1] )
+      byteSwapBuffer( buffer, samples, format );
+
+    // Do buffer conversion if necessary.
+    if ( stream_.doConvertBuffer[1] )
+      convertBuffer( stream_.userBuffer[1], stream_.deviceBuffer, stream_.convertInfo[1] );
+  }
+
+ unlock:
+  MUTEX_UNLOCK( &stream_.mutex );
+
+  RtApi::tickStreamTime();
+  if ( doStopStream == 1 ) this->stopStream();
+}
+
+static void *ossCallbackHandler( void *ptr )
+{
+  CallbackInfo *info = (CallbackInfo *) ptr;
+  RtApiOss *object = (RtApiOss *) info->object;
+  bool *isRunning = &info->isRunning;
+
+  while ( *isRunning == true ) {
+    pthread_testcancel();
+    object->callbackEvent();
+  }
+
+  pthread_exit( NULL );
+}
+
+//******************** End of __LINUX_OSS__ *********************//
+#endif
+
+
+// *************************************************** //
+//
+// Protected common (OS-independent) RtAudio methods.
+//
+// *************************************************** //
+
+// This method can be modified to control the behavior of error
+// message printing.
+void RtApi :: error( RtAudioError::Type type )
+{
+  errorStream_.str(""); // clear the ostringstream
+
+  RtAudioErrorCallback errorCallback = (RtAudioErrorCallback) stream_.callbackInfo.errorCallback;
+  if ( errorCallback ) {
+    // abortStream() can generate new error messages. Ignore them. Just keep original one.
+
+    if ( firstErrorOccurred_ )
+      return;
+
+    firstErrorOccurred_ = true;
+    const std::string errorMessage = errorText_;
+
+    if ( type != RtAudioError::WARNING && stream_.state != STREAM_STOPPED) {
+      stream_.callbackInfo.isRunning = false; // exit from the thread
+      abortStream();
+    }
+
+    errorCallback( type, errorMessage );
+    firstErrorOccurred_ = false;
+    return;
+  }
+
+  if ( type == RtAudioError::WARNING && showWarnings_ == true )
+    std::cerr << '\n' << errorText_ << "\n\n";
+  else if ( type != RtAudioError::WARNING )
+    throw( RtAudioError( errorText_, type ) );
+}
+
+void RtApi :: verifyStream()
+{
+  if ( stream_.state == STREAM_CLOSED ) {
+    errorText_ = "RtApi:: a stream is not open!";
+    error( RtAudioError::INVALID_USE );
+  }
+}
+
+void RtApi :: clearStreamInfo()
+{
+  stream_.mode = UNINITIALIZED;
+  stream_.state = STREAM_CLOSED;
+  stream_.sampleRate = 0;
+  stream_.bufferSize = 0;
+  stream_.nBuffers = 0;
+  stream_.userFormat = 0;
+  stream_.userInterleaved = true;
+  stream_.streamTime = 0.0;
+  stream_.apiHandle = 0;
+  stream_.deviceBuffer = 0;
+  stream_.callbackInfo.callback = 0;
+  stream_.callbackInfo.userData = 0;
+  stream_.callbackInfo.isRunning = false;
+  stream_.callbackInfo.errorCallback = 0;
+  for ( int i=0; i<2; i++ ) {
+    stream_.device[i] = 11111;
+    stream_.doConvertBuffer[i] = false;
+    stream_.deviceInterleaved[i] = true;
+    stream_.doByteSwap[i] = false;
+    stream_.nUserChannels[i] = 0;
+    stream_.nDeviceChannels[i] = 0;
+    stream_.channelOffset[i] = 0;
+    stream_.deviceFormat[i] = 0;
+    stream_.latency[i] = 0;
+    stream_.userBuffer[i] = 0;
+    stream_.convertInfo[i].channels = 0;
+    stream_.convertInfo[i].inJump = 0;
+    stream_.convertInfo[i].outJump = 0;
+    stream_.convertInfo[i].inFormat = 0;
+    stream_.convertInfo[i].outFormat = 0;
+    stream_.convertInfo[i].inOffset.clear();
+    stream_.convertInfo[i].outOffset.clear();
+  }
+}
+
+unsigned int RtApi :: formatBytes( RtAudioFormat format )
+{
+  if ( format == RTAUDIO_SINT16 )
+    return 2;
+  else if ( format == RTAUDIO_SINT32 || format == RTAUDIO_FLOAT32 )
+    return 4;
+  else if ( format == RTAUDIO_FLOAT64 )
+    return 8;
+  else if ( format == RTAUDIO_SINT24 )
+    return 3;
+  else if ( format == RTAUDIO_SINT8 )
+    return 1;
+
+  errorText_ = "RtApi::formatBytes: undefined format.";
+  error( RtAudioError::WARNING );
+
+  return 0;
+}
+
+void RtApi :: setConvertInfo( StreamMode mode, unsigned int firstChannel )
+{
+  if ( mode == INPUT ) { // convert device to user buffer
+    stream_.convertInfo[mode].inJump = stream_.nDeviceChannels[1];
+    stream_.convertInfo[mode].outJump = stream_.nUserChannels[1];
+    stream_.convertInfo[mode].inFormat = stream_.deviceFormat[1];
+    stream_.convertInfo[mode].outFormat = stream_.userFormat;
+  }
+  else { // convert user to device buffer
+    stream_.convertInfo[mode].inJump = stream_.nUserChannels[0];
+    stream_.convertInfo[mode].outJump = stream_.nDeviceChannels[0];
+    stream_.convertInfo[mode].inFormat = stream_.userFormat;
+    stream_.convertInfo[mode].outFormat = stream_.deviceFormat[0];
+  }
+
+  if ( stream_.convertInfo[mode].inJump < stream_.convertInfo[mode].outJump )
+    stream_.convertInfo[mode].channels = stream_.convertInfo[mode].inJump;
+  else
+    stream_.convertInfo[mode].channels = stream_.convertInfo[mode].outJump;
+
+  // Set up the interleave/deinterleave offsets.
+  if ( stream_.deviceInterleaved[mode] != stream_.userInterleaved ) {
+    if ( ( mode == OUTPUT && stream_.deviceInterleaved[mode] ) ||
+         ( mode == INPUT && stream_.userInterleaved ) ) {
+      for ( int k=0; k<stream_.convertInfo[mode].channels; k++ ) {
+        stream_.convertInfo[mode].inOffset.push_back( k * stream_.bufferSize );
+        stream_.convertInfo[mode].outOffset.push_back( k );
+        stream_.convertInfo[mode].inJump = 1;
+      }
+    }
+    else {
+      for ( int k=0; k<stream_.convertInfo[mode].channels; k++ ) {
+        stream_.convertInfo[mode].inOffset.push_back( k );
+        stream_.convertInfo[mode].outOffset.push_back( k * stream_.bufferSize );
+        stream_.convertInfo[mode].outJump = 1;
+      }
+    }
+  }
+  else { // no (de)interleaving
+    if ( stream_.userInterleaved ) {
+      for ( int k=0; k<stream_.convertInfo[mode].channels; k++ ) {
+        stream_.convertInfo[mode].inOffset.push_back( k );
+        stream_.convertInfo[mode].outOffset.push_back( k );
+      }
+    }
+    else {
+      for ( int k=0; k<stream_.convertInfo[mode].channels; k++ ) {
+        stream_.convertInfo[mode].inOffset.push_back( k * stream_.bufferSize );
+        stream_.convertInfo[mode].outOffset.push_back( k * stream_.bufferSize );
+        stream_.convertInfo[mode].inJump = 1;
+        stream_.convertInfo[mode].outJump = 1;
+      }
+    }
+  }
+
+  // Add channel offset.
+  if ( firstChannel > 0 ) {
+    if ( stream_.deviceInterleaved[mode] ) {
+      if ( mode == OUTPUT ) {
+        for ( int k=0; k<stream_.convertInfo[mode].channels; k++ )
+          stream_.convertInfo[mode].outOffset[k] += firstChannel;
+      }
+      else {
+        for ( int k=0; k<stream_.convertInfo[mode].channels; k++ )
+          stream_.convertInfo[mode].inOffset[k] += firstChannel;
+      }
+    }
+    else {
+      if ( mode == OUTPUT ) {
+        for ( int k=0; k<stream_.convertInfo[mode].channels; k++ )
+          stream_.convertInfo[mode].outOffset[k] += ( firstChannel * stream_.bufferSize );
+      }
+      else {
+        for ( int k=0; k<stream_.convertInfo[mode].channels; k++ )
+          stream_.convertInfo[mode].inOffset[k] += ( firstChannel  * stream_.bufferSize );
+      }
+    }
+  }
+}
+
+void RtApi :: convertBuffer( char *outBuffer, char *inBuffer, ConvertInfo &info )
+{
+  // This function does format conversion, input/output channel compensation, and
+  // data interleaving/deinterleaving.  24-bit integers are assumed to occupy
+  // the lower three bytes of a 32-bit integer.
+
+  // Clear our device buffer when in/out duplex device channels are different
+  if ( outBuffer == stream_.deviceBuffer && stream_.mode == DUPLEX &&
+       ( stream_.nDeviceChannels[0] < stream_.nDeviceChannels[1] ) )
+    memset( outBuffer, 0, stream_.bufferSize * info.outJump * formatBytes( info.outFormat ) );
+
+  int j;
+  if (info.outFormat == RTAUDIO_FLOAT64) {
+    Float64 scale;
+    Float64 *out = (Float64 *)outBuffer;
+
+    if (info.inFormat == RTAUDIO_SINT8) {
+      signed char *in = (signed char *)inBuffer;
+      scale = 1.0 / 127.5;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float64) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT16) {
+      Int16 *in = (Int16 *)inBuffer;
+      scale = 1.0 / 32767.5;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float64) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      Int24 *in = (Int24 *)inBuffer;
+      scale = 1.0 / 8388607.5;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float64) (in[info.inOffset[j]].asInt());
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      Int32 *in = (Int32 *)inBuffer;
+      scale = 1.0 / 2147483647.5;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float64) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float64) in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      // Channel compensation and/or (de)interleaving only.
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+  else if (info.outFormat == RTAUDIO_FLOAT32) {
+    Float32 scale;
+    Float32 *out = (Float32 *)outBuffer;
+
+    if (info.inFormat == RTAUDIO_SINT8) {
+      signed char *in = (signed char *)inBuffer;
+      scale = (Float32) ( 1.0 / 127.5 );
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float32) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT16) {
+      Int16 *in = (Int16 *)inBuffer;
+      scale = (Float32) ( 1.0 / 32767.5 );
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float32) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      Int24 *in = (Int24 *)inBuffer;
+      scale = (Float32) ( 1.0 / 8388607.5 );
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float32) (in[info.inOffset[j]].asInt());
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      Int32 *in = (Int32 *)inBuffer;
+      scale = (Float32) ( 1.0 / 2147483647.5 );
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float32) in[info.inOffset[j]];
+          out[info.outOffset[j]] += 0.5;
+          out[info.outOffset[j]] *= scale;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      // Channel compensation and/or (de)interleaving only.
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Float32) in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+  else if (info.outFormat == RTAUDIO_SINT32) {
+    Int32 *out = (Int32 *)outBuffer;
+    if (info.inFormat == RTAUDIO_SINT8) {
+      signed char *in = (signed char *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) in[info.inOffset[j]];
+          out[info.outOffset[j]] <<= 24;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT16) {
+      Int16 *in = (Int16 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) in[info.inOffset[j]];
+          out[info.outOffset[j]] <<= 16;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      Int24 *in = (Int24 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) in[info.inOffset[j]].asInt();
+          out[info.outOffset[j]] <<= 8;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      // Channel compensation and/or (de)interleaving only.
+      Int32 *in = (Int32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] * 2147483647.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] * 2147483647.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+  else if (info.outFormat == RTAUDIO_SINT24) {
+    Int24 *out = (Int24 *)outBuffer;
+    if (info.inFormat == RTAUDIO_SINT8) {
+      signed char *in = (signed char *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] << 16);
+          //out[info.outOffset[j]] <<= 16;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT16) {
+      Int16 *in = (Int16 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] << 8);
+          //out[info.outOffset[j]] <<= 8;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      // Channel compensation and/or (de)interleaving only.
+      Int24 *in = (Int24 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      Int32 *in = (Int32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] >> 8);
+          //out[info.outOffset[j]] >>= 8;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] * 8388607.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int32) (in[info.inOffset[j]] * 8388607.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+  else if (info.outFormat == RTAUDIO_SINT16) {
+    Int16 *out = (Int16 *)outBuffer;
+    if (info.inFormat == RTAUDIO_SINT8) {
+      signed char *in = (signed char *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int16) in[info.inOffset[j]];
+          out[info.outOffset[j]] <<= 8;
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT16) {
+      // Channel compensation and/or (de)interleaving only.
+      Int16 *in = (Int16 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      Int24 *in = (Int24 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int16) (in[info.inOffset[j]].asInt() >> 8);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      Int32 *in = (Int32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int16) ((in[info.inOffset[j]] >> 16) & 0x0000ffff);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int16) (in[info.inOffset[j]] * 32767.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (Int16) (in[info.inOffset[j]] * 32767.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+  else if (info.outFormat == RTAUDIO_SINT8) {
+    signed char *out = (signed char *)outBuffer;
+    if (info.inFormat == RTAUDIO_SINT8) {
+      // Channel compensation and/or (de)interleaving only.
+      signed char *in = (signed char *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = in[info.inOffset[j]];
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    if (info.inFormat == RTAUDIO_SINT16) {
+      Int16 *in = (Int16 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (signed char) ((in[info.inOffset[j]] >> 8) & 0x00ff);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT24) {
+      Int24 *in = (Int24 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (signed char) (in[info.inOffset[j]].asInt() >> 16);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_SINT32) {
+      Int32 *in = (Int32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (signed char) ((in[info.inOffset[j]] >> 24) & 0x000000ff);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT32) {
+      Float32 *in = (Float32 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (signed char) (in[info.inOffset[j]] * 127.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+    else if (info.inFormat == RTAUDIO_FLOAT64) {
+      Float64 *in = (Float64 *)inBuffer;
+      for (unsigned int i=0; i<stream_.bufferSize; i++) {
+        for (j=0; j<info.channels; j++) {
+          out[info.outOffset[j]] = (signed char) (in[info.inOffset[j]] * 127.5 - 0.5);
+        }
+        in += info.inJump;
+        out += info.outJump;
+      }
+    }
+  }
+}
+
+//static inline uint16_t bswap_16(uint16_t x) { return (x>>8) | (x<<8); }
+//static inline uint32_t bswap_32(uint32_t x) { return (bswap_16(x&0xffff)<<16) | (bswap_16(x>>16)); }
+//static inline uint64_t bswap_64(uint64_t x) { return (((unsigned long long)bswap_32(x&0xffffffffull))<<32) | (bswap_32(x>>32)); }
+
+void RtApi :: byteSwapBuffer( char *buffer, unsigned int samples, RtAudioFormat format )
+{
+  char val;
+  char *ptr;
+
+  ptr = buffer;
+  if ( format == RTAUDIO_SINT16 ) {
+    for ( unsigned int i=0; i<samples; i++ ) {
+      // Swap 1st and 2nd bytes.
+      val = *(ptr);
+      *(ptr) = *(ptr+1);
+      *(ptr+1) = val;
+
+      // Increment 2 bytes.
+      ptr += 2;
+    }
+  }
+  else if ( format == RTAUDIO_SINT32 ||
+            format == RTAUDIO_FLOAT32 ) {
+    for ( unsigned int i=0; i<samples; i++ ) {
+      // Swap 1st and 4th bytes.
+      val = *(ptr);
+      *(ptr) = *(ptr+3);
+      *(ptr+3) = val;
+
+      // Swap 2nd and 3rd bytes.
+      ptr += 1;
+      val = *(ptr);
+      *(ptr) = *(ptr+1);
+      *(ptr+1) = val;
+
+      // Increment 3 more bytes.
+      ptr += 3;
+    }
+  }
+  else if ( format == RTAUDIO_SINT24 ) {
+    for ( unsigned int i=0; i<samples; i++ ) {
+      // Swap 1st and 3rd bytes.
+      val = *(ptr);
+      *(ptr) = *(ptr+2);
+      *(ptr+2) = val;
+
+      // Increment 2 more bytes.
+      ptr += 2;
+    }
+  }
+  else if ( format == RTAUDIO_FLOAT64 ) {
+    for ( unsigned int i=0; i<samples; i++ ) {
+      // Swap 1st and 8th bytes
+      val = *(ptr);
+      *(ptr) = *(ptr+7);
+      *(ptr+7) = val;
+
+      // Swap 2nd and 7th bytes
+      ptr += 1;
+      val = *(ptr);
+      *(ptr) = *(ptr+5);
+      *(ptr+5) = val;
+
+      // Swap 3rd and 6th bytes
+      ptr += 1;
+      val = *(ptr);
+      *(ptr) = *(ptr+3);
+      *(ptr+3) = val;
+
+      // Swap 4th and 5th bytes
+      ptr += 1;
+      val = *(ptr);
+      *(ptr) = *(ptr+1);
+      *(ptr+1) = val;
+
+      // Increment 5 more bytes.
+      ptr += 5;
+    }
+  }
+}
+
+  // Indentation settings for Vim and Emacs
+  //
+  // Local Variables:
+  // c-basic-offset: 2
+  // indent-tabs-mode: nil
+  // End:
+  //
+  // vim: et sts=2 sw=2
+
diff --git a/RtAudio/RtAudio.h b/RtAudio/RtAudio.h
new file mode 100644
index 0000000..11345cc
--- /dev/null
+++ b/RtAudio/RtAudio.h
@@ -0,0 +1,1163 @@
+/************************************************************************/
+/*! \class RtAudio
+    \brief Realtime audio i/o C++ classes.
+
+    RtAudio provides a common API (Application Programming Interface)
+    for realtime audio input/output across Linux (native ALSA, Jack,
+    and OSS), Macintosh OS X (CoreAudio and Jack), and Windows
+    (DirectSound, ASIO and WASAPI) operating systems.
+
+    RtAudio WWW site: http://www.music.mcgill.ca/~gary/rtaudio/
+
+    RtAudio: realtime audio i/o C++ classes
+    Copyright (c) 2001-2016 Gary P. Scavone
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation files
+    (the "Software"), to deal in the Software without restriction,
+    including without limitation the rights to use, copy, modify, merge,
+    publish, distribute, sublicense, and/or sell copies of the Software,
+    and to permit persons to whom the Software is furnished to do so,
+    subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    Any person wishing to distribute modifications to the Software is
+    asked to send the modifications to the original developer so that
+    they can be incorporated into the canonical version.  This is,
+    however, not a binding provision of this license.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+    ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+    CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+/************************************************************************/
+
+/*!
+  \file RtAudio.h
+ */
+
+#ifndef __RTAUDIO_H
+#define __RTAUDIO_H
+
+#define RTAUDIO_VERSION "4.1.2"
+
+#include <string>
+#include <vector>
+#include <exception>
+#include <iostream>
+
+/*! \typedef typedef unsigned long RtAudioFormat;
+    \brief RtAudio data format type.
+
+    Support for signed integers and floats.  Audio data fed to/from an
+    RtAudio stream is assumed to ALWAYS be in host byte order.  The
+    internal routines will automatically take care of any necessary
+    byte-swapping between the host format and the soundcard.  Thus,
+    endian-ness is not a concern in the following format definitions.
+
+    - \e RTAUDIO_SINT8:   8-bit signed integer.
+    - \e RTAUDIO_SINT16:  16-bit signed integer.
+    - \e RTAUDIO_SINT24:  24-bit signed integer.
+    - \e RTAUDIO_SINT32:  32-bit signed integer.
+    - \e RTAUDIO_FLOAT32: Normalized between plus/minus 1.0.
+    - \e RTAUDIO_FLOAT64: Normalized between plus/minus 1.0.
+*/
+typedef unsigned long RtAudioFormat;
+static const RtAudioFormat RTAUDIO_SINT8 = 0x1;    // 8-bit signed integer.
+static const RtAudioFormat RTAUDIO_SINT16 = 0x2;   // 16-bit signed integer.
+static const RtAudioFormat RTAUDIO_SINT24 = 0x4;   // 24-bit signed integer.
+static const RtAudioFormat RTAUDIO_SINT32 = 0x8;   // 32-bit signed integer.
+static const RtAudioFormat RTAUDIO_FLOAT32 = 0x10; // Normalized between plus/minus 1.0.
+static const RtAudioFormat RTAUDIO_FLOAT64 = 0x20; // Normalized between plus/minus 1.0.
+
+/*! \typedef typedef unsigned long RtAudioStreamFlags;
+    \brief RtAudio stream option flags.
+
+    The following flags can be OR'ed together to allow a client to
+    make changes to the default stream behavior:
+
+    - \e RTAUDIO_NONINTERLEAVED:   Use non-interleaved buffers (default = interleaved).
+    - \e RTAUDIO_MINIMIZE_LATENCY: Attempt to set stream parameters for lowest possible latency.
+    - \e RTAUDIO_HOG_DEVICE:       Attempt grab device for exclusive use.
+    - \e RTAUDIO_ALSA_USE_DEFAULT: Use the "default" PCM device (ALSA only).
+
+    By default, RtAudio streams pass and receive audio data from the
+    client in an interleaved format.  By passing the
+    RTAUDIO_NONINTERLEAVED flag to the openStream() function, audio
+    data will instead be presented in non-interleaved buffers.  In
+    this case, each buffer argument in the RtAudioCallback function
+    will point to a single array of data, with \c nFrames samples for
+    each channel concatenated back-to-back.  For example, the first
+    sample of data for the second channel would be located at index \c
+    nFrames (assuming the \c buffer pointer was recast to the correct
+    data type for the stream).
+
+    Certain audio APIs offer a number of parameters that influence the
+    I/O latency of a stream.  By default, RtAudio will attempt to set
+    these parameters internally for robust (glitch-free) performance
+    (though some APIs, like Windows Direct Sound, make this difficult).
+    By passing the RTAUDIO_MINIMIZE_LATENCY flag to the openStream()
+    function, internal stream settings will be influenced in an attempt
+    to minimize stream latency, though possibly at the expense of stream
+    performance.
+
+    If the RTAUDIO_HOG_DEVICE flag is set, RtAudio will attempt to
+    open the input and/or output stream device(s) for exclusive use.
+    Note that this is not possible with all supported audio APIs.
+
+    If the RTAUDIO_SCHEDULE_REALTIME flag is set, RtAudio will attempt 
+    to select realtime scheduling (round-robin) for the callback thread.
+
+    If the RTAUDIO_ALSA_USE_DEFAULT flag is set, RtAudio will attempt to
+    open the "default" PCM device when using the ALSA API. Note that this
+    will override any specified input or output device id.
+*/
+typedef unsigned int RtAudioStreamFlags;
+static const RtAudioStreamFlags RTAUDIO_NONINTERLEAVED = 0x1;    // Use non-interleaved buffers (default = interleaved).
+static const RtAudioStreamFlags RTAUDIO_MINIMIZE_LATENCY = 0x2;  // Attempt to set stream parameters for lowest possible latency.
+static const RtAudioStreamFlags RTAUDIO_HOG_DEVICE = 0x4;        // Attempt grab device and prevent use by others.
+static const RtAudioStreamFlags RTAUDIO_SCHEDULE_REALTIME = 0x8; // Try to select realtime scheduling for callback thread.
+static const RtAudioStreamFlags RTAUDIO_ALSA_USE_DEFAULT = 0x10; // Use the "default" PCM device (ALSA only).
+
+/*! \typedef typedef unsigned long RtAudioStreamStatus;
+    \brief RtAudio stream status (over- or underflow) flags.
+
+    Notification of a stream over- or underflow is indicated by a
+    non-zero stream \c status argument in the RtAudioCallback function.
+    The stream status can be one of the following two options,
+    depending on whether the stream is open for output and/or input:
+
+    - \e RTAUDIO_INPUT_OVERFLOW:   Input data was discarded because of an overflow condition at the driver.
+    - \e RTAUDIO_OUTPUT_UNDERFLOW: The output buffer ran low, likely producing a break in the output sound.
+*/
+typedef unsigned int RtAudioStreamStatus;
+static const RtAudioStreamStatus RTAUDIO_INPUT_OVERFLOW = 0x1;    // Input data was discarded because of an overflow condition at the driver.
+static const RtAudioStreamStatus RTAUDIO_OUTPUT_UNDERFLOW = 0x2;  // The output buffer ran low, likely causing a gap in the output sound.
+
+//! RtAudio callback function prototype.
+/*!
+   All RtAudio clients must create a function of type RtAudioCallback
+   to read and/or write data from/to the audio stream.  When the
+   underlying audio system is ready for new input or output data, this
+   function will be invoked.
+
+   \param outputBuffer For output (or duplex) streams, the client
+          should write \c nFrames of audio sample frames into this
+          buffer.  This argument should be recast to the datatype
+          specified when the stream was opened.  For input-only
+          streams, this argument will be NULL.
+
+   \param inputBuffer For input (or duplex) streams, this buffer will
+          hold \c nFrames of input audio sample frames.  This
+          argument should be recast to the datatype specified when the
+          stream was opened.  For output-only streams, this argument
+          will be NULL.
+
+   \param nFrames The number of sample frames of input or output
+          data in the buffers.  The actual buffer size in bytes is
+          dependent on the data type and number of channels in use.
+
+   \param streamTime The number of seconds that have elapsed since the
+          stream was started.
+
+   \param status If non-zero, this argument indicates a data overflow
+          or underflow condition for the stream.  The particular
+          condition can be determined by comparison with the
+          RtAudioStreamStatus flags.
+
+   \param userData A pointer to optional data provided by the client
+          when opening the stream (default = NULL).
+
+   To continue normal stream operation, the RtAudioCallback function
+   should return a value of zero.  To stop the stream and drain the
+   output buffer, the function should return a value of one.  To abort
+   the stream immediately, the client should return a value of two.
+ */
+typedef int (*RtAudioCallback)( void *outputBuffer, void *inputBuffer,
+                                unsigned int nFrames,
+                                double streamTime,
+                                RtAudioStreamStatus status,
+                                void *userData );
+
+/************************************************************************/
+/*! \class RtAudioError
+    \brief Exception handling class for RtAudio.
+
+    The RtAudioError class is quite simple but it does allow errors to be
+    "caught" by RtAudioError::Type. See the RtAudio documentation to know
+    which methods can throw an RtAudioError.
+*/
+/************************************************************************/
+
+class RtAudioError : public std::exception
+{
+ public:
+  //! Defined RtAudioError types.
+  enum Type {
+    WARNING,           /*!< A non-critical error. */
+    DEBUG_WARNING,     /*!< A non-critical error which might be useful for debugging. */
+    UNSPECIFIED,       /*!< The default, unspecified error type. */
+    NO_DEVICES_FOUND,  /*!< No devices found on system. */
+    INVALID_DEVICE,    /*!< An invalid device ID was specified. */
+    MEMORY_ERROR,      /*!< An error occured during memory allocation. */
+    INVALID_PARAMETER, /*!< An invalid parameter was specified to a function. */
+    INVALID_USE,       /*!< The function was called incorrectly. */
+    DRIVER_ERROR,      /*!< A system driver error occured. */
+    SYSTEM_ERROR,      /*!< A system error occured. */
+    THREAD_ERROR       /*!< A thread error occured. */
+  };
+
+  //! The constructor.
+  RtAudioError( const std::string& message, Type type = RtAudioError::UNSPECIFIED ) throw() : message_(message), type_(type) {}
+ 
+  //! The destructor.
+  virtual ~RtAudioError( void ) throw() {}
+
+  //! Prints thrown error message to stderr.
+  virtual void printMessage( void ) const throw() { std::cerr << '\n' << message_ << "\n\n"; }
+
+  //! Returns the thrown error message type.
+  virtual const Type& getType(void) const throw() { return type_; }
+
+  //! Returns the thrown error message string.
+  virtual const std::string& getMessage(void) const throw() { return message_; }
+
+  //! Returns the thrown error message as a c-style string.
+  virtual const char* what( void ) const throw() { return message_.c_str(); }
+
+ protected:
+  std::string message_;
+  Type type_;
+};
+
+//! RtAudio error callback function prototype.
+/*!
+    \param type Type of error.
+    \param errorText Error description.
+ */
+typedef void (*RtAudioErrorCallback)( RtAudioError::Type type, const std::string &errorText );
+
+// **************************************************************** //
+//
+// RtAudio class declaration.
+//
+// RtAudio is a "controller" used to select an available audio i/o
+// interface.  It presents a common API for the user to call but all
+// functionality is implemented by the class RtApi and its
+// subclasses.  RtAudio creates an instance of an RtApi subclass
+// based on the user's API choice.  If no choice is made, RtAudio
+// attempts to make a "logical" API selection.
+//
+// **************************************************************** //
+
+class RtApi;
+
+class RtAudio
+{
+ public:
+
+  //! Audio API specifier arguments.
+  enum Api {
+    UNSPECIFIED,    /*!< Search for a working compiled API. */
+    LINUX_ALSA,     /*!< The Advanced Linux Sound Architecture API. */
+    LINUX_PULSE,    /*!< The Linux PulseAudio API. */
+    LINUX_OSS,      /*!< The Linux Open Sound System API. */
+    UNIX_JACK,      /*!< The Jack Low-Latency Audio Server API. */
+    MACOSX_CORE,    /*!< Macintosh OS-X Core Audio API. */
+    WINDOWS_WASAPI, /*!< The Microsoft WASAPI API. */
+    WINDOWS_ASIO,   /*!< The Steinberg Audio Stream I/O API. */
+    WINDOWS_DS,     /*!< The Microsoft Direct Sound API. */
+    RTAUDIO_DUMMY   /*!< A compilable but non-functional API. */
+  };
+
+  //! The public device information structure for returning queried values.
+  struct DeviceInfo {
+    bool probed;                  /*!< true if the device capabilities were successfully probed. */
+    std::string name;             /*!< Character string device identifier. */
+    unsigned int outputChannels;  /*!< Maximum output channels supported by device. */
+    unsigned int inputChannels;   /*!< Maximum input channels supported by device. */
+    unsigned int duplexChannels;  /*!< Maximum simultaneous input/output channels supported by device. */
+    bool isDefaultOutput;         /*!< true if this is the default output device. */
+    bool isDefaultInput;          /*!< true if this is the default input device. */
+    std::vector<unsigned int> sampleRates; /*!< Supported sample rates (queried from list of standard rates). */
+    unsigned int preferredSampleRate; /*!< Preferred sample rate, eg. for WASAPI the system sample rate. */
+    RtAudioFormat nativeFormats;  /*!< Bit mask of supported data formats. */
+
+    // Default constructor.
+    DeviceInfo()
+      :probed(false), outputChannels(0), inputChannels(0), duplexChannels(0),
+       isDefaultOutput(false), isDefaultInput(false), preferredSampleRate(0), nativeFormats(0) {}
+  };
+
+  //! The structure for specifying input or ouput stream parameters.
+  struct StreamParameters {
+    unsigned int deviceId;     /*!< Device index (0 to getDeviceCount() - 1). */
+    unsigned int nChannels;    /*!< Number of channels. */
+    unsigned int firstChannel; /*!< First channel index on device (default = 0). */
+
+    // Default constructor.
+    StreamParameters()
+      : deviceId(0), nChannels(0), firstChannel(0) {}
+  };
+
+  //! The structure for specifying stream options.
+  /*!
+    The following flags can be OR'ed together to allow a client to
+    make changes to the default stream behavior:
+
+    - \e RTAUDIO_NONINTERLEAVED:    Use non-interleaved buffers (default = interleaved).
+    - \e RTAUDIO_MINIMIZE_LATENCY:  Attempt to set stream parameters for lowest possible latency.
+    - \e RTAUDIO_HOG_DEVICE:        Attempt grab device for exclusive use.
+    - \e RTAUDIO_SCHEDULE_REALTIME: Attempt to select realtime scheduling for callback thread.
+    - \e RTAUDIO_ALSA_USE_DEFAULT:  Use the "default" PCM device (ALSA only).
+
+    By default, RtAudio streams pass and receive audio data from the
+    client in an interleaved format.  By passing the
+    RTAUDIO_NONINTERLEAVED flag to the openStream() function, audio
+    data will instead be presented in non-interleaved buffers.  In
+    this case, each buffer argument in the RtAudioCallback function
+    will point to a single array of data, with \c nFrames samples for
+    each channel concatenated back-to-back.  For example, the first
+    sample of data for the second channel would be located at index \c
+    nFrames (assuming the \c buffer pointer was recast to the correct
+    data type for the stream).
+
+    Certain audio APIs offer a number of parameters that influence the
+    I/O latency of a stream.  By default, RtAudio will attempt to set
+    these parameters internally for robust (glitch-free) performance
+    (though some APIs, like Windows Direct Sound, make this difficult).
+    By passing the RTAUDIO_MINIMIZE_LATENCY flag to the openStream()
+    function, internal stream settings will be influenced in an attempt
+    to minimize stream latency, though possibly at the expense of stream
+    performance.
+
+    If the RTAUDIO_HOG_DEVICE flag is set, RtAudio will attempt to
+    open the input and/or output stream device(s) for exclusive use.
+    Note that this is not possible with all supported audio APIs.
+
+    If the RTAUDIO_SCHEDULE_REALTIME flag is set, RtAudio will attempt 
+    to select realtime scheduling (round-robin) for the callback thread.
+    The \c priority parameter will only be used if the RTAUDIO_SCHEDULE_REALTIME
+    flag is set. It defines the thread's realtime priority.
+
+    If the RTAUDIO_ALSA_USE_DEFAULT flag is set, RtAudio will attempt to
+    open the "default" PCM device when using the ALSA API. Note that this
+    will override any specified input or output device id.
+
+    The \c numberOfBuffers parameter can be used to control stream
+    latency in the Windows DirectSound, Linux OSS, and Linux Alsa APIs
+    only.  A value of two is usually the smallest allowed.  Larger
+    numbers can potentially result in more robust stream performance,
+    though likely at the cost of stream latency.  The value set by the
+    user is replaced during execution of the RtAudio::openStream()
+    function by the value actually used by the system.
+
+    The \c streamName parameter can be used to set the client name
+    when using the Jack API.  By default, the client name is set to
+    RtApiJack.  However, if you wish to create multiple instances of
+    RtAudio with Jack, each instance must have a unique client name.
+  */
+  struct StreamOptions {
+    RtAudioStreamFlags flags;      /*!< A bit-mask of stream flags (RTAUDIO_NONINTERLEAVED, RTAUDIO_MINIMIZE_LATENCY, RTAUDIO_HOG_DEVICE, RTAUDIO_ALSA_USE_DEFAULT). */
+    unsigned int numberOfBuffers;  /*!< Number of stream buffers. */
+    std::string streamName;        /*!< A stream name (currently used only in Jack). */
+    int priority;                  /*!< Scheduling priority of callback thread (only used with flag RTAUDIO_SCHEDULE_REALTIME). */
+
+    // Default constructor.
+    StreamOptions()
+    : flags(0), numberOfBuffers(0), priority(0) {}
+  };
+
+  //! A static function to determine the current RtAudio version.
+  static std::string getVersion( void ) throw();
+
+  //! A static function to determine the available compiled audio APIs.
+  /*!
+    The values returned in the std::vector can be compared against
+    the enumerated list values.  Note that there can be more than one
+    API compiled for certain operating systems.
+  */
+  static void getCompiledApi( std::vector<RtAudio::Api> &apis ) throw();
+
+  //! The class constructor.
+  /*!
+    The constructor performs minor initialization tasks.  An exception
+    can be thrown if no API support is compiled.
+
+    If no API argument is specified and multiple API support has been
+    compiled, the default order of use is JACK, ALSA, OSS (Linux
+    systems) and ASIO, DS (Windows systems).
+  */
+  RtAudio( RtAudio::Api api=UNSPECIFIED );
+
+  //! The destructor.
+  /*!
+    If a stream is running or open, it will be stopped and closed
+    automatically.
+  */
+  ~RtAudio() throw();
+
+  //! Returns the audio API specifier for the current instance of RtAudio.
+  RtAudio::Api getCurrentApi( void ) throw();
+
+  //! A public function that queries for the number of audio devices available.
+  /*!
+    This function performs a system query of available devices each time it
+    is called, thus supporting devices connected \e after instantiation. If
+    a system error occurs during processing, a warning will be issued. 
+  */
+  unsigned int getDeviceCount( void ) throw();
+
+  //! Return an RtAudio::DeviceInfo structure for a specified device number.
+  /*!
+
+    Any device integer between 0 and getDeviceCount() - 1 is valid.
+    If an invalid argument is provided, an RtAudioError (type = INVALID_USE)
+    will be thrown.  If a device is busy or otherwise unavailable, the
+    structure member "probed" will have a value of "false" and all
+    other members are undefined.  If the specified device is the
+    current default input or output device, the corresponding
+    "isDefault" member will have a value of "true".
+  */
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+
+  //! A function that returns the index of the default output device.
+  /*!
+    If the underlying audio API does not provide a "default
+    device", or if no devices are available, the return value will be
+    0.  Note that this is a valid device identifier and it is the
+    client's responsibility to verify that a device is available
+    before attempting to open a stream.
+  */
+  unsigned int getDefaultOutputDevice( void ) throw();
+
+  //! A function that returns the index of the default input device.
+  /*!
+    If the underlying audio API does not provide a "default
+    device", or if no devices are available, the return value will be
+    0.  Note that this is a valid device identifier and it is the
+    client's responsibility to verify that a device is available
+    before attempting to open a stream.
+  */
+  unsigned int getDefaultInputDevice( void ) throw();
+
+  //! A public function for opening a stream with the specified parameters.
+  /*!
+    An RtAudioError (type = SYSTEM_ERROR) is thrown if a stream cannot be
+    opened with the specified parameters or an error occurs during
+    processing.  An RtAudioError (type = INVALID_USE) is thrown if any
+    invalid device ID or channel number parameters are specified.
+
+    \param outputParameters Specifies output stream parameters to use
+           when opening a stream, including a device ID, number of channels,
+           and starting channel number.  For input-only streams, this
+           argument should be NULL.  The device ID is an index value between
+           0 and getDeviceCount() - 1.
+    \param inputParameters Specifies input stream parameters to use
+           when opening a stream, including a device ID, number of channels,
+           and starting channel number.  For output-only streams, this
+           argument should be NULL.  The device ID is an index value between
+           0 and getDeviceCount() - 1.
+    \param format An RtAudioFormat specifying the desired sample data format.
+    \param sampleRate The desired sample rate (sample frames per second).
+    \param *bufferFrames A pointer to a value indicating the desired
+           internal buffer size in sample frames.  The actual value
+           used by the device is returned via the same pointer.  A
+           value of zero can be specified, in which case the lowest
+           allowable value is determined.
+    \param callback A client-defined function that will be invoked
+           when input data is available and/or output data is needed.
+    \param userData An optional pointer to data that can be accessed
+           from within the callback function.
+    \param options An optional pointer to a structure containing various
+           global stream options, including a list of OR'ed RtAudioStreamFlags
+           and a suggested number of stream buffers that can be used to 
+           control stream latency.  More buffers typically result in more
+           robust performance, though at a cost of greater latency.  If a
+           value of zero is specified, a system-specific median value is
+           chosen.  If the RTAUDIO_MINIMIZE_LATENCY flag bit is set, the
+           lowest allowable value is used.  The actual value used is
+           returned via the structure argument.  The parameter is API dependent.
+    \param errorCallback A client-defined function that will be invoked
+           when an error has occured.
+  */
+  void openStream( RtAudio::StreamParameters *outputParameters,
+                   RtAudio::StreamParameters *inputParameters,
+                   RtAudioFormat format, unsigned int sampleRate,
+                   unsigned int *bufferFrames, RtAudioCallback callback,
+                   void *userData = NULL, RtAudio::StreamOptions *options = NULL, RtAudioErrorCallback errorCallback = NULL );
+
+  //! A function that closes a stream and frees any associated stream memory.
+  /*!
+    If a stream is not open, this function issues a warning and
+    returns (no exception is thrown).
+  */
+  void closeStream( void ) throw();
+
+  //! A function that starts a stream.
+  /*!
+    An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
+    during processing.  An RtAudioError (type = INVALID_USE) is thrown if a
+    stream is not open.  A warning is issued if the stream is already
+    running.
+  */
+  void startStream( void );
+
+  //! Stop a stream, allowing any samples remaining in the output queue to be played.
+  /*!
+    An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
+    during processing.  An RtAudioError (type = INVALID_USE) is thrown if a
+    stream is not open.  A warning is issued if the stream is already
+    stopped.
+  */
+  void stopStream( void );
+
+  //! Stop a stream, discarding any samples remaining in the input/output queue.
+  /*!
+    An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
+    during processing.  An RtAudioError (type = INVALID_USE) is thrown if a
+    stream is not open.  A warning is issued if the stream is already
+    stopped.
+  */
+  void abortStream( void );
+
+  //! Returns true if a stream is open and false if not.
+  bool isStreamOpen( void ) const throw();
+
+  //! Returns true if the stream is running and false if it is stopped or not open.
+  bool isStreamRunning( void ) const throw();
+
+  //! Returns the number of elapsed seconds since the stream was started.
+  /*!
+    If a stream is not open, an RtAudioError (type = INVALID_USE) will be thrown.
+  */
+  double getStreamTime( void );
+
+  //! Set the stream time to a time in seconds greater than or equal to 0.0.
+  /*!
+    If a stream is not open, an RtAudioError (type = INVALID_USE) will be thrown.
+  */
+  void setStreamTime( double time );
+
+  //! Returns the internal stream latency in sample frames.
+  /*!
+    The stream latency refers to delay in audio input and/or output
+    caused by internal buffering by the audio system and/or hardware.
+    For duplex streams, the returned value will represent the sum of
+    the input and output latencies.  If a stream is not open, an
+    RtAudioError (type = INVALID_USE) will be thrown.  If the API does not
+    report latency, the return value will be zero.
+  */
+  long getStreamLatency( void );
+
+ //! Returns actual sample rate in use by the stream.
+ /*!
+   On some systems, the sample rate used may be slightly different
+   than that specified in the stream parameters.  If a stream is not
+   open, an RtAudioError (type = INVALID_USE) will be thrown.
+ */
+  unsigned int getStreamSampleRate( void );
+
+  //! Specify whether warning messages should be printed to stderr.
+  void showWarnings( bool value = true ) throw();
+
+ protected:
+
+  void openRtApi( RtAudio::Api api );
+  RtApi *rtapi_;
+};
+
+// Operating system dependent thread functionality.
+#if defined(__WINDOWS_DS__) || defined(__WINDOWS_ASIO__) || defined(__WINDOWS_WASAPI__)
+
+  #ifndef NOMINMAX
+    #define NOMINMAX
+  #endif
+  #include <windows.h>
+  #include <process.h>
+
+  typedef uintptr_t ThreadHandle;
+  typedef CRITICAL_SECTION StreamMutex;
+
+#elif defined(__LINUX_ALSA__) || defined(__LINUX_PULSE__) || defined(__UNIX_JACK__) || defined(__LINUX_OSS__) || defined(__MACOSX_CORE__)
+  // Using pthread library for various flavors of unix.
+  #include <pthread.h>
+
+  typedef pthread_t ThreadHandle;
+  typedef pthread_mutex_t StreamMutex;
+
+#else // Setup for "dummy" behavior
+
+  #define __RTAUDIO_DUMMY__
+  typedef int ThreadHandle;
+  typedef int StreamMutex;
+
+#endif
+
+// This global structure type is used to pass callback information
+// between the private RtAudio stream structure and global callback
+// handling functions.
+struct CallbackInfo {
+  void *object;    // Used as a "this" pointer.
+  ThreadHandle thread;
+  void *callback;
+  void *userData;
+  void *errorCallback;
+  void *apiInfo;   // void pointer for API specific callback information
+  bool isRunning;
+  bool doRealtime;
+  int priority;
+
+  // Default constructor.
+  CallbackInfo()
+  :object(0), callback(0), userData(0), errorCallback(0), apiInfo(0), isRunning(false), doRealtime(false) {}
+};
+
+// **************************************************************** //
+//
+// RtApi class declaration.
+//
+// Subclasses of RtApi contain all API- and OS-specific code necessary
+// to fully implement the RtAudio API.
+//
+// Note that RtApi is an abstract base class and cannot be
+// explicitly instantiated.  The class RtAudio will create an
+// instance of an RtApi subclass (RtApiOss, RtApiAlsa,
+// RtApiJack, RtApiCore, RtApiDs, or RtApiAsio).
+//
+// **************************************************************** //
+
+#pragma pack(push, 1)
+class S24 {
+
+ protected:
+  unsigned char c3[3];
+
+ public:
+  S24() {}
+
+  S24& operator = ( const int& i ) {
+    c3[0] = (i & 0x000000ff);
+    c3[1] = (i & 0x0000ff00) >> 8;
+    c3[2] = (i & 0x00ff0000) >> 16;
+    return *this;
+  }
+
+  S24( const S24& v ) { *this = v; }
+  S24( const double& d ) { *this = (int) d; }
+  S24( const float& f ) { *this = (int) f; }
+  S24( const signed short& s ) { *this = (int) s; }
+  S24( const char& c ) { *this = (int) c; }
+
+  int asInt() {
+    int i = c3[0] | (c3[1] << 8) | (c3[2] << 16);
+    if (i & 0x800000) i |= ~0xffffff;
+    return i;
+  }
+};
+#pragma pack(pop)
+
+#if defined( HAVE_GETTIMEOFDAY )
+  #include <sys/time.h>
+#endif
+
+#include <sstream>
+
+class RtApi
+{
+public:
+
+  RtApi();
+  virtual ~RtApi();
+  virtual RtAudio::Api getCurrentApi( void ) = 0;
+  virtual unsigned int getDeviceCount( void ) = 0;
+  virtual RtAudio::DeviceInfo getDeviceInfo( unsigned int device ) = 0;
+  virtual unsigned int getDefaultInputDevice( void );
+  virtual unsigned int getDefaultOutputDevice( void );
+  void openStream( RtAudio::StreamParameters *outputParameters,
+                   RtAudio::StreamParameters *inputParameters,
+                   RtAudioFormat format, unsigned int sampleRate,
+                   unsigned int *bufferFrames, RtAudioCallback callback,
+                   void *userData, RtAudio::StreamOptions *options,
+                   RtAudioErrorCallback errorCallback );
+  virtual void closeStream( void );
+  virtual void startStream( void ) = 0;
+  virtual void stopStream( void ) = 0;
+  virtual void abortStream( void ) = 0;
+  long getStreamLatency( void );
+  unsigned int getStreamSampleRate( void );
+  virtual double getStreamTime( void );
+  virtual void setStreamTime( double time );
+  bool isStreamOpen( void ) const { return stream_.state != STREAM_CLOSED; }
+  bool isStreamRunning( void ) const { return stream_.state == STREAM_RUNNING; }
+  void showWarnings( bool value ) { showWarnings_ = value; }
+
+
+protected:
+
+  static const unsigned int MAX_SAMPLE_RATES;
+  static const unsigned int SAMPLE_RATES[];
+
+  enum { FAILURE, SUCCESS };
+
+  enum StreamState {
+    STREAM_STOPPED,
+    STREAM_STOPPING,
+    STREAM_RUNNING,
+    STREAM_CLOSED = -50
+  };
+
+  enum StreamMode {
+    OUTPUT,
+    INPUT,
+    DUPLEX,
+    UNINITIALIZED = -75
+  };
+
+  // A protected structure used for buffer conversion.
+  struct ConvertInfo {
+    int channels;
+    int inJump, outJump;
+    RtAudioFormat inFormat, outFormat;
+    std::vector<int> inOffset;
+    std::vector<int> outOffset;
+  };
+
+  // A protected structure for audio streams.
+  struct RtApiStream {
+    unsigned int device[2];    // Playback and record, respectively.
+    void *apiHandle;           // void pointer for API specific stream handle information
+    StreamMode mode;           // OUTPUT, INPUT, or DUPLEX.
+    StreamState state;         // STOPPED, RUNNING, or CLOSED
+    char *userBuffer[2];       // Playback and record, respectively.
+    char *deviceBuffer;
+    bool doConvertBuffer[2];   // Playback and record, respectively.
+    bool userInterleaved;
+    bool deviceInterleaved[2]; // Playback and record, respectively.
+    bool doByteSwap[2];        // Playback and record, respectively.
+    unsigned int sampleRate;
+    unsigned int bufferSize;
+    unsigned int nBuffers;
+    unsigned int nUserChannels[2];    // Playback and record, respectively.
+    unsigned int nDeviceChannels[2];  // Playback and record channels, respectively.
+    unsigned int channelOffset[2];    // Playback and record, respectively.
+    unsigned long latency[2];         // Playback and record, respectively.
+    RtAudioFormat userFormat;
+    RtAudioFormat deviceFormat[2];    // Playback and record, respectively.
+    StreamMutex mutex;
+    CallbackInfo callbackInfo;
+    ConvertInfo convertInfo[2];
+    double streamTime;         // Number of elapsed seconds since the stream started.
+
+#if defined(HAVE_GETTIMEOFDAY)
+    struct timeval lastTickTimestamp;
+#endif
+
+    RtApiStream()
+      :apiHandle(0), deviceBuffer(0) { device[0] = 11111; device[1] = 11111; }
+  };
+
+  typedef S24 Int24;
+  typedef signed short Int16;
+  typedef signed int Int32;
+  typedef float Float32;
+  typedef double Float64;
+
+  std::ostringstream errorStream_;
+  std::string errorText_;
+  bool showWarnings_;
+  RtApiStream stream_;
+  bool firstErrorOccurred_;
+
+  /*!
+    Protected, api-specific method that attempts to open a device
+    with the given parameters.  This function MUST be implemented by
+    all subclasses.  If an error is encountered during the probe, a
+    "warning" message is reported and FAILURE is returned. A
+    successful probe is indicated by a return value of SUCCESS.
+  */
+  virtual bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                                unsigned int firstChannel, unsigned int sampleRate,
+                                RtAudioFormat format, unsigned int *bufferSize,
+                                RtAudio::StreamOptions *options );
+
+  //! A protected function used to increment the stream time.
+  void tickStreamTime( void );
+
+  //! Protected common method to clear an RtApiStream structure.
+  void clearStreamInfo();
+
+  /*!
+    Protected common method that throws an RtAudioError (type =
+    INVALID_USE) if a stream is not open.
+  */
+  void verifyStream( void );
+
+  //! Protected common error method to allow global control over error handling.
+  void error( RtAudioError::Type type );
+
+  /*!
+    Protected method used to perform format, channel number, and/or interleaving
+    conversions between the user and device buffers.
+  */
+  void convertBuffer( char *outBuffer, char *inBuffer, ConvertInfo &info );
+
+  //! Protected common method used to perform byte-swapping on buffers.
+  void byteSwapBuffer( char *buffer, unsigned int samples, RtAudioFormat format );
+
+  //! Protected common method that returns the number of bytes for a given format.
+  unsigned int formatBytes( RtAudioFormat format );
+
+  //! Protected common method that sets up the parameters for buffer conversion.
+  void setConvertInfo( StreamMode mode, unsigned int firstChannel );
+};
+
+// **************************************************************** //
+//
+// Inline RtAudio definitions.
+//
+// **************************************************************** //
+
+inline RtAudio::Api RtAudio :: getCurrentApi( void ) throw() { return rtapi_->getCurrentApi(); }
+inline unsigned int RtAudio :: getDeviceCount( void ) throw() { return rtapi_->getDeviceCount(); }
+inline RtAudio::DeviceInfo RtAudio :: getDeviceInfo( unsigned int device ) { return rtapi_->getDeviceInfo( device ); }
+inline unsigned int RtAudio :: getDefaultInputDevice( void ) throw() { return rtapi_->getDefaultInputDevice(); }
+inline unsigned int RtAudio :: getDefaultOutputDevice( void ) throw() { return rtapi_->getDefaultOutputDevice(); }
+inline void RtAudio :: closeStream( void ) throw() { return rtapi_->closeStream(); }
+inline void RtAudio :: startStream( void ) { return rtapi_->startStream(); }
+inline void RtAudio :: stopStream( void )  { return rtapi_->stopStream(); }
+inline void RtAudio :: abortStream( void ) { return rtapi_->abortStream(); }
+inline bool RtAudio :: isStreamOpen( void ) const throw() { return rtapi_->isStreamOpen(); }
+inline bool RtAudio :: isStreamRunning( void ) const throw() { return rtapi_->isStreamRunning(); }
+inline long RtAudio :: getStreamLatency( void ) { return rtapi_->getStreamLatency(); }
+inline unsigned int RtAudio :: getStreamSampleRate( void ) { return rtapi_->getStreamSampleRate(); }
+inline double RtAudio :: getStreamTime( void ) { return rtapi_->getStreamTime(); }
+inline void RtAudio :: setStreamTime( double time ) { return rtapi_->setStreamTime( time ); }
+inline void RtAudio :: showWarnings( bool value ) throw() { rtapi_->showWarnings( value ); }
+
+// RtApi Subclass prototypes.
+
+#if defined(__MACOSX_CORE__)
+
+#include <CoreAudio/AudioHardware.h>
+
+class RtApiCore: public RtApi
+{
+public:
+
+  RtApiCore();
+  ~RtApiCore();
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::MACOSX_CORE; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  unsigned int getDefaultOutputDevice( void );
+  unsigned int getDefaultInputDevice( void );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+  long getStreamLatency( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  bool callbackEvent( AudioDeviceID deviceId,
+                      const AudioBufferList *inBufferList,
+                      const AudioBufferList *outBufferList );
+
+  private:
+
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+  static const char* getErrorCode( OSStatus code );
+};
+
+#endif
+
+#if defined(__UNIX_JACK__)
+
+class RtApiJack: public RtApi
+{
+public:
+
+  RtApiJack();
+  ~RtApiJack();
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::UNIX_JACK; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+  long getStreamLatency( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  bool callbackEvent( unsigned long nframes );
+
+  private:
+
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__WINDOWS_ASIO__)
+
+class RtApiAsio: public RtApi
+{
+public:
+
+  RtApiAsio();
+  ~RtApiAsio();
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_ASIO; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+  long getStreamLatency( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  bool callbackEvent( long bufferIndex );
+
+  private:
+
+  std::vector<RtAudio::DeviceInfo> devices_;
+  void saveDeviceInfo( void );
+  bool coInitialized_;
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__WINDOWS_DS__)
+
+class RtApiDs: public RtApi
+{
+public:
+
+  RtApiDs();
+  ~RtApiDs();
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_DS; }
+  unsigned int getDeviceCount( void );
+  unsigned int getDefaultOutputDevice( void );
+  unsigned int getDefaultInputDevice( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+  long getStreamLatency( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  void callbackEvent( void );
+
+  private:
+
+  bool coInitialized_;
+  bool buffersRolling;
+  long duplexPrerollBytes;
+  std::vector<struct DsDevice> dsDevices;
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__WINDOWS_WASAPI__)
+
+struct IMMDeviceEnumerator;
+
+class RtApiWasapi : public RtApi
+{
+public:
+  RtApiWasapi();
+  ~RtApiWasapi();
+
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_WASAPI; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  unsigned int getDefaultOutputDevice( void );
+  unsigned int getDefaultInputDevice( void );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+
+private:
+  bool coInitialized_;
+  IMMDeviceEnumerator* deviceEnumerator_;
+
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int* bufferSize,
+                        RtAudio::StreamOptions* options );
+
+  static DWORD WINAPI runWasapiThread( void* wasapiPtr );
+  static DWORD WINAPI stopWasapiThread( void* wasapiPtr );
+  static DWORD WINAPI abortWasapiThread( void* wasapiPtr );
+  void wasapiThread();
+};
+
+#endif
+
+#if defined(__LINUX_ALSA__)
+
+class RtApiAlsa: public RtApi
+{
+public:
+
+  RtApiAlsa();
+  ~RtApiAlsa();
+  RtAudio::Api getCurrentApi() { return RtAudio::LINUX_ALSA; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  void callbackEvent( void );
+
+  private:
+
+  std::vector<RtAudio::DeviceInfo> devices_;
+  void saveDeviceInfo( void );
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__LINUX_PULSE__)
+
+class RtApiPulse: public RtApi
+{
+public:
+  ~RtApiPulse();
+  RtAudio::Api getCurrentApi() { return RtAudio::LINUX_PULSE; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  void callbackEvent( void );
+
+  private:
+
+  std::vector<RtAudio::DeviceInfo> devices_;
+  void saveDeviceInfo( void );
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__LINUX_OSS__)
+
+class RtApiOss: public RtApi
+{
+public:
+
+  RtApiOss();
+  ~RtApiOss();
+  RtAudio::Api getCurrentApi() { return RtAudio::LINUX_OSS; }
+  unsigned int getDeviceCount( void );
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
+  void closeStream( void );
+  void startStream( void );
+  void stopStream( void );
+  void abortStream( void );
+
+  // This function is intended for internal use only.  It must be
+  // public because it is called by the internal callback handler,
+  // which is not a member of RtAudio.  External use of this function
+  // will most likely produce highly undesireable results!
+  void callbackEvent( void );
+
+  private:
+
+  bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels, 
+                        unsigned int firstChannel, unsigned int sampleRate,
+                        RtAudioFormat format, unsigned int *bufferSize,
+                        RtAudio::StreamOptions *options );
+};
+
+#endif
+
+#if defined(__RTAUDIO_DUMMY__)
+
+class RtApiDummy: public RtApi
+{
+public:
+
+  RtApiDummy() { errorText_ = "RtApiDummy: This class provides no functionality."; error( RtAudioError::WARNING ); }
+  RtAudio::Api getCurrentApi( void ) { return RtAudio::RTAUDIO_DUMMY; }
+  unsigned int getDeviceCount( void ) { return 0; }
+  RtAudio::DeviceInfo getDeviceInfo( unsigned int /*device*/ ) { RtAudio::DeviceInfo info; return info; }
+  void closeStream( void ) {}
+  void startStream( void ) {}
+  void stopStream( void ) {}
+  void abortStream( void ) {}
+
+  private:
+
+  bool probeDeviceOpen( unsigned int /*device*/, StreamMode /*mode*/, unsigned int /*channels*/, 
+                        unsigned int /*firstChannel*/, unsigned int /*sampleRate*/,
+                        RtAudioFormat /*format*/, unsigned int * /*bufferSize*/,
+                        RtAudio::StreamOptions * /*options*/ ) { return false; }
+};
+
+#endif
+
+#endif
+
+// Indentation settings for Vim and Emacs
+//
+// Local Variables:
+// c-basic-offset: 2
+// indent-tabs-mode: nil
+// End:
+//
+// vim: et sts=2 sw=2
diff --git a/RtAudio/readme b/RtAudio/readme
new file mode 100644
index 0000000..079875f
--- /dev/null
+++ b/RtAudio/readme
@@ -0,0 +1,61 @@
+RtAudio - a set of C++ classes that provide a common API for realtime audio input/output across Linux (native ALSA, JACK, PulseAudio and OSS), Macintosh OS X (CoreAudio and JACK), and Windows (DirectSound, ASIO and WASAPI) operating systems.
+
+By Gary P. Scavone, 2001-2016.
+
+This distribution of RtAudio contains the following:
+
+doc:      RtAudio documentation (see doc/html/index.html)
+tests:    example RtAudio programs
+include:  header and source files necessary for ASIO, DS & OSS compilation
+tests/Windows: Visual C++ .net test program workspace and projects
+
+OVERVIEW:
+
+RtAudio is a set of C++ classes that provides a common API (Application Programming Interface) for realtime audio input/output across Linux (native ALSA, JACK, PulseAudio and OSS), Macintosh OS X and Windows (DirectSound, ASIO and WASAPI) operating systems.  RtAudio significantly simplifies the process of interacting with computer audio hardware.  It was designed with the following objectives:
+
+  - object-oriented C++ design
+  - simple, common API across all supported platforms
+  - only one source and one header file for easy inclusion in programming projects
+  - allow simultaneous multi-api support
+  - support dynamic connection of devices
+  - provide extensive audio device parameter control
+  - allow audio device capability probing
+  - automatic internal conversion for data format, channel number compensation, (de)interleaving, and byte-swapping
+
+RtAudio incorporates the concept of audio streams, which represent audio output (playback) and/or input (recording).  Available audio devices and their capabilities can be enumerated and then specified when opening a stream.  Where applicable, multiple API support can be compiled and a particular API specified when creating an RtAudio instance.  See the \ref apinotes section for information specific to each of the supported audio APIs.
+
+FURTHER READING:
+
+For complete documentation on RtAudio, see the doc directory of the distribution or surf to http://www.music.mcgill.ca/~gary/rtaudio/.
+
+
+LEGAL AND ETHICAL:
+
+The RtAudio license is similar to the MIT License.
+
+    RtAudio: a set of realtime audio i/o C++ classes
+    Copyright (c) 2001-2016 Gary P. Scavone
+
+    Permission is hereby granted, free of charge, to any person
+    obtaining a copy of this software and associated documentation files
+    (the "Software"), to deal in the Software without restriction,
+    including without limitation the rights to use, copy, modify, merge,
+    publish, distribute, sublicense, and/or sell copies of the Software,
+    and to permit persons to whom the Software is furnished to do so,
+    subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    Any person wishing to distribute modifications to the Software is
+    asked to send the modifications to the original developer so that
+    they can be incorporated into the canonical version.  This is,
+    however, not a binding provision of this license.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+    ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+    CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/Settings.cpp b/Settings.cpp
new file mode 100644
index 0000000..172e5e4
--- /dev/null
+++ b/Settings.cpp
@@ -0,0 +1,603 @@
+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2015 Charles J. Cliffe
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "SoapyAudio.hpp"
+
+#ifdef USE_HAMLIB
+std::vector<const struct rig_caps *> SoapyAudio::rigCaps;
+#endif
+
+SoapyAudio::SoapyAudio(const SoapySDR::Kwargs &args)
+{
+    deviceId = -1;
+
+    asFormat = AUDIO_FORMAT_FLOAT32;
+
+    sampleRate = 48000;
+    centerFrequency = 0;
+
+    numBuffers = DEFAULT_NUM_BUFFERS;
+
+    agcMode = false;
+
+    bufferedElems = 0;
+    resetBuffer = false;
+    
+    streamActive = false;
+    sampleRateChanged.store(false);
+    
+    sampleOffset = 0;
+
+    if (args.count("device_id") != 0)
+    {
+        try {
+            deviceId = std::stoi(args.at("device_id"));
+        } catch (const std::invalid_argument &) {
+        }
+        
+        int numDevices = dac.getDeviceCount();
+        
+        if (deviceId < 0 || deviceId >= numDevices)
+        {
+            throw std::runtime_error(
+                    "device_id out of range [0 .. " + std::to_string(numDevices) + "].");
+        }
+  
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "Found Audio device using 'device_id' = %d", deviceId);
+    }
+    
+    if (deviceId == -1) {
+        throw std::runtime_error("device_id missing.");
+    }
+
+    RtAudio endac;
+    
+    devInfo = endac.getDeviceInfo(deviceId);
+    
+#ifdef USE_HAMLIB
+    t_Rig = nullptr;
+    rigThread = nullptr;
+    rigModel = 0;
+    rigFile = "";
+    rigSerialRate = 0;
+    
+    if (args.count("rig") != 0 && args.at("rig") != "") {
+        try {
+            rigModel = std::stoi(args.at("rig"));
+        } catch (const std::invalid_argument &) {
+            throw std::runtime_error("rig is invalid.");
+        }
+        if (!args.count("rig_rate")) {
+            throw std::runtime_error("rig_rate missing.");
+        }
+        try {
+            rigSerialRate = std::stoi(args.at("rig_rate"));
+        } catch (const std::invalid_argument &) {
+            throw std::runtime_error("rig_rate is invalid.");
+        }
+
+        if (!args.count("rig_port")) {
+            throw std::runtime_error("rig_port missing.");
+        }
+        rigFile = args.at("rig_port");
+        checkRigThread();
+    }
+#endif
+}
+
+SoapyAudio::~SoapyAudio(void)
+{
+#ifdef USE_HAMLIB
+    if (rigThread) {
+        if (!rigThread->isTerminated()) {
+            rigThread->terminate();
+        }
+        if (t_Rig && t_Rig->joinable()) {
+            t_Rig->join();
+        }
+    }
+#endif
+}
+
+/*******************************************************************
+ * Identification API
+ ******************************************************************/
+
+std::string SoapyAudio::getDriverKey(void) const
+{
+    return "Audio";
+}
+
+std::string SoapyAudio::getHardwareKey(void) const
+{
+    return "Audio";
+}
+
+SoapySDR::Kwargs SoapyAudio::getHardwareInfo(void) const
+{
+    //key/value pairs for any useful information
+    //this also gets printed in --probe
+    SoapySDR::Kwargs args;
+
+    args["origin"] = "https://github.com/pothosware/SoapyAudio";
+    args["device_id"] = std::to_string(deviceId);
+
+    return args;
+}
+
+/*******************************************************************
+ * Channels API
+ ******************************************************************/
+
+size_t SoapyAudio::getNumChannels(const int dir) const
+{
+    return (dir == SOAPY_SDR_RX) ? 1 : 0;
+}
+
+/*******************************************************************
+ * Antenna API
+ ******************************************************************/
+
+std::vector<std::string> SoapyAudio::listAntennas(const int direction, const size_t channel) const
+{
+    std::vector<std::string> antennas;
+    antennas.push_back("RX");
+    // antennas.push_back("TX");
+    return antennas;
+}
+
+void SoapyAudio::setAntenna(const int direction, const size_t channel, const std::string &name)
+{
+    // TODO
+}
+
+std::string SoapyAudio::getAntenna(const int direction, const size_t channel) const
+{
+    return "RX";
+    // return "TX";
+}
+
+/*******************************************************************
+ * Frontend corrections API
+ ******************************************************************/
+
+bool SoapyAudio::hasDCOffsetMode(const int direction, const size_t channel) const
+{
+    return false;
+}
+
+/*******************************************************************
+ * Gain API
+ ******************************************************************/
+
+std::vector<std::string> SoapyAudio::listGains(const int direction, const size_t channel) const
+{
+    //list available gain elements,
+    //the functions below have a "name" parameter
+    std::vector<std::string> results;
+
+    // results.push_back("AUDIO");
+
+    return results;
+}
+
+bool SoapyAudio::hasGainMode(const int direction, const size_t channel) const
+{
+    return true;
+}
+
+void SoapyAudio::setGainMode(const int direction, const size_t channel, const bool automatic)
+{
+    agcMode = automatic;
+    SoapySDR_logf(SOAPY_SDR_DEBUG, "Setting Audio AGC: %s", automatic ? "Automatic" : "Manual");
+}
+
+bool SoapyAudio::getGainMode(const int direction, const size_t channel) const
+{
+    return agcMode;
+}
+
+void SoapyAudio::setGain(const int direction, const size_t channel, const double value)
+{
+    //set the overall gain by distributing it across available gain elements
+    //OR delete this function to use SoapySDR's default gain distribution algorithm...
+    SoapySDR::Device::setGain(direction, channel, value);
+}
+
+void SoapyAudio::setGain(const int direction, const size_t channel, const std::string &name, const double value)
+{
+    if (name == "AUDIO")
+    {
+        audioGain = value;
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "Setting Audio Gain: %f", audioGain);
+    }
+}
+
+double SoapyAudio::getGain(const int direction, const size_t channel, const std::string &name) const
+{
+    if ((name.length() >= 2) && (name.substr(0, 2) == "AUDIO"))
+    {
+        return audioGain;
+    }
+
+    return 0;
+}
+
+SoapySDR::Range SoapyAudio::getGainRange(const int direction, const size_t channel, const std::string &name) const
+{
+    return SoapySDR::Range(0, 100);
+}
+
+/*******************************************************************
+ * Frequency API
+ ******************************************************************/
+
+void SoapyAudio::setFrequency(
+        const int direction,
+        const size_t channel,
+        const std::string &name,
+        const double frequency,
+        const SoapySDR::Kwargs &args)
+{
+    if (name == "RF")
+    {
+        centerFrequency = (uint32_t) frequency;
+        resetBuffer = true;
+        SoapySDR_logf(SOAPY_SDR_DEBUG, "Setting center freq: %d", centerFrequency);
+#ifdef USE_HAMLIB
+        if (rigThread && !rigThread->isTerminated()) {
+            if (rigThread->getFrequency() != frequency) {
+                rigThread->setFrequency(frequency);
+            }
+        }
+#endif
+    }
+}
+
+double SoapyAudio::getFrequency(const int direction, const size_t channel, const std::string &name) const
+{
+    if (name == "RF")
+    {
+#ifdef USE_HAMLIB
+        if (rigThread && !rigThread->isTerminated()) {
+            return rigThread->getFrequency();
+        }
+#endif
+        return (double) centerFrequency;
+    }
+
+    return 0;
+}
+
+std::vector<std::string> SoapyAudio::listFrequencies(const int direction, const size_t channel) const
+{
+    std::vector<std::string> names;
+    names.push_back("RF");
+    return names;
+}
+
+SoapySDR::RangeList SoapyAudio::getFrequencyRange(
+        const int direction,
+        const size_t channel,
+        const std::string &name) const
+{
+    SoapySDR::RangeList results;
+    if (name == "RF")
+    {
+        results.push_back(SoapySDR::Range(0, 6000000000));
+    }
+    return results;
+}
+
+SoapySDR::ArgInfoList SoapyAudio::getFrequencyArgsInfo(const int direction, const size_t channel) const
+{
+    SoapySDR::ArgInfoList freqArgs;
+
+    // TODO: frequency arguments
+
+    return freqArgs;
+}
+
+/*******************************************************************
+ * Sample Rate API
+ ******************************************************************/
+
+void SoapyAudio::setSampleRate(const int direction, const size_t channel, const double rate)
+{
+    SoapySDR_logf(SOAPY_SDR_DEBUG, "Setting sample rate: %d", sampleRate);
+
+    if (sampleRate != rate) {
+        sampleRate = rate;
+        resetBuffer = true;
+        sampleRateChanged.store(true);
+    }
+}
+
+double SoapyAudio::getSampleRate(const int direction, const size_t channel) const
+{
+    return sampleRate;
+}
+
+std::vector<double> SoapyAudio::listSampleRates(const int direction, const size_t channel) const
+{
+    std::vector<double> results;
+
+    RtAudio endac;
+    RtAudio::DeviceInfo info = endac.getDeviceInfo(deviceId);
+
+    std::vector<unsigned int>::iterator srate;
+
+    for (srate = info.sampleRates.begin(); srate != info.sampleRates.end(); srate++) {
+        results.push_back(*srate);
+    }
+
+    return results;
+}
+
+void SoapyAudio::setBandwidth(const int direction, const size_t channel, const double bw)
+{
+    SoapySDR::Device::setBandwidth(direction, channel, bw);
+}
+
+double SoapyAudio::getBandwidth(const int direction, const size_t channel) const
+{
+    return SoapySDR::Device::getBandwidth(direction, channel);
+}
+
+std::vector<double> SoapyAudio::listBandwidths(const int direction, const size_t channel) const
+{
+    std::vector<double> results;
+
+    return results;
+}
+
+/*******************************************************************
+ * Settings API
+ ******************************************************************/
+
+SoapySDR::ArgInfoList SoapyAudio::getSettingInfo(void) const
+{
+    SoapySDR::ArgInfoList setArgs;
+
+    // Sample Offset
+    SoapySDR::ArgInfo sampleOffsetArg;
+    sampleOffsetArg.key = "sample_offset";
+    sampleOffsetArg.value = "0";
+    sampleOffsetArg.name = "Stereo Sample Offset";
+    sampleOffsetArg.description = "Offset stereo samples for off-by-one audio inputs.";
+    sampleOffsetArg.type = SoapySDR::ArgInfo::STRING;
+    
+    std::vector<std::string> sampleOffsetOpts;
+    std::vector<std::string> sampleOffsetOptNames;
+
+    sampleOffsetOpts.push_back("-2");
+    sampleOffsetOptNames.push_back("-2 Samples");
+    sampleOffsetOpts.push_back("-1");
+    sampleOffsetOptNames.push_back("-1 Samples");
+    sampleOffsetOpts.push_back("0");
+    sampleOffsetOptNames.push_back("0 Samples");
+    sampleOffsetOpts.push_back("1");
+    sampleOffsetOptNames.push_back("1 Samples");
+    sampleOffsetOpts.push_back("2");
+    sampleOffsetOptNames.push_back("2 Samples");
+
+    sampleOffsetArg.options = sampleOffsetOpts;
+    sampleOffsetArg.optionNames = sampleOffsetOptNames;
+
+    setArgs.push_back(sampleOffsetArg);
+
+#ifdef USE_HAMLIB
+    // Rig Control
+    SoapySDR::ArgInfo rigArg;
+    rigArg.key = "rig";
+    rigArg.value = "";
+    rigArg.name = "Rig Control";
+    rigArg.description = "Select hamlib rig control type.";
+    rigArg.type = SoapySDR::ArgInfo::STRING;
+    
+    std::vector<std::string> rigOpts;
+    std::vector<std::string> rigOptNames;
+
+    rigOpts.push_back("");
+    rigOptNames.push_back("None");
+    
+    for (std::vector<const struct rig_caps *>::const_iterator i = rigCaps.begin(); i != rigCaps.end(); i++) {
+        const struct rig_caps *rc = (*i);
+
+        rigOpts.push_back(std::to_string(rc->rig_model));
+        rigOptNames.push_back(std::string(rc->mfg_name) + " " + std::string(rc->model_name));
+    }
+
+    rigArg.options = rigOpts;
+    rigArg.optionNames = rigOptNames;
+
+    setArgs.push_back(rigArg);
+
+    // Rig Control
+    SoapySDR::ArgInfo rigRateArg;
+    rigRateArg.key = "rig_rate";
+    rigRateArg.value = "57600";
+    rigRateArg.name = "Rig Serial Rate";
+    rigRateArg.description = "Select hamlib rig serial control rate.";
+    rigRateArg.type = SoapySDR::ArgInfo::STRING;
+    
+    std::vector<std::string> rigRateOpts;
+    std::vector<std::string> rigRateOptNames;
+
+    rigRateOpts.push_back("1200");
+    rigRateOptNames.push_back("1200 baud");
+    rigRateOpts.push_back("2400");
+    rigRateOptNames.push_back("2400 baud");
+    rigRateOpts.push_back("4800");
+    rigRateOptNames.push_back("4800 baud");
+    rigRateOpts.push_back("9600");
+    rigRateOptNames.push_back("9600 baud");
+    rigRateOpts.push_back("19200");
+    rigRateOptNames.push_back("19200 baud");
+    rigRateOpts.push_back("38400");
+    rigRateOptNames.push_back("38400 baud");
+    rigRateOpts.push_back("57600");
+    rigRateOptNames.push_back("57600 baud");
+    rigRateOpts.push_back("115200");
+    rigRateOptNames.push_back("115200 baud");
+    rigRateOpts.push_back("128000");
+    rigRateOptNames.push_back("128000 baud");
+    rigRateOpts.push_back("256000");
+    rigRateOptNames.push_back("256000 baud");
+
+    rigRateArg.options = rigRateOpts;
+    rigRateArg.optionNames = rigRateOptNames;
+
+    setArgs.push_back(rigRateArg);
+
+    SoapySDR::ArgInfo rigFileArg;
+    rigFileArg.key = "rig_port";
+    rigFileArg.value = "/dev/ttyUSB0";
+    rigFileArg.name = "Rig Serial Port";
+    rigFileArg.description = "hamlib rig Serial Port dev / COMx / IP-Address";
+    rigFileArg.type = SoapySDR::ArgInfo::STRING;
+    
+    setArgs.push_back(rigFileArg);
+    
+#endif
+    
+    return setArgs;
+}
+
+void SoapyAudio::writeSetting(const std::string &key, const std::string &value)
+{
+    if (key == "sample_offset") {
+        try {
+            int sOffset = std::stoi(value);
+            
+            if (sOffset >= -2 && sOffset <= 2) {
+                sampleOffset = sOffset;
+            }
+        } catch (std::invalid_argument e) { }
+    }
+    
+    
+#ifdef USE_HAMLIB   
+    bool rigReset = false; 
+    if (key == "rig")
+    {
+        try {
+            rig_model_t newModel = std::stoi(value);
+            if (newModel != rigModel) {
+                rigReset = true;
+                rigModel = newModel;
+            }
+        } catch (const std::invalid_argument &) {
+            rigModel = 0;
+        }
+    }
+
+    if (key == "rig_rate")
+    {
+        try {
+            int newSerialRate = std::stoi(value);
+            if (newSerialRate != rigSerialRate) {
+                rigSerialRate = newSerialRate;
+                rigReset = true;
+            }
+        } catch (const std::invalid_argument &) {
+            rigSerialRate = 57600;
+        }
+    }
+
+    if (key == "rig_port")
+    {
+        if (rigFile != value) {
+            rigFile = value;
+            rigReset = true;
+        }
+    }
+    
+    if (rigReset) {
+        if (rigThread && !rigThread->isTerminated()) {
+            rigThread->terminate();
+        }
+        checkRigThread();        
+    }
+#endif
+}
+
+std::string SoapyAudio::readSetting(const std::string &key) const
+{
+    if (key == "sample_offset") {
+        return std::to_string(sampleOffset);
+    }
+    
+#ifdef USE_HAMLIB
+    if (key == "rig")
+    {
+        return std::to_string(rigModel);
+    }
+    if (key == "rig_rate")
+    {
+        return std::to_string(rigSerialRate);
+    }
+    if (key == "rig_port")
+    {
+        return rigFile;
+    }
+#endif
+    // SoapySDR_logf(SOAPY_SDR_WARNING, "Unknown setting '%s'", key.c_str());
+    return "";
+}
+
+
+chanSetup SoapyAudio::chanSetupStrToEnum(std::string chanOpt) {
+    if (chanOpt == "mono_l") {
+        return FORMAT_MONO_L;
+    } else if (chanOpt == "mono_r") {
+        return FORMAT_MONO_R;
+    } else if (chanOpt == "stereo_iq") {
+        return FORMAT_STEREO_IQ;
+    } else if (chanOpt == "stereo_qi") {
+        return FORMAT_STEREO_QI;
+    } else {
+        return FORMAT_MONO_L;
+    }
+}
+
+#ifdef USE_HAMLIB
+void SoapyAudio::checkRigThread() {    
+    if (!rigModel || !rigSerialRate || rigFile == "") {
+        return;
+    }
+    if (!rigThread) {
+        rigThread = new RigThread();
+    }
+    if (rigThread->isTerminated()) {
+        if (t_Rig && t_Rig->joinable()) {
+            t_Rig->join();
+            delete t_Rig;
+        }
+        rigThread->setup(rigModel, rigFile, rigSerialRate);
+        t_Rig = new std::thread(&RigThread::threadMain, rigThread);
+    }
+}
+
+#endif
\ No newline at end of file
diff --git a/SoapyAudio.hpp b/SoapyAudio.hpp
new file mode 100644
index 0000000..6eefb76
--- /dev/null
+++ b/SoapyAudio.hpp
@@ -0,0 +1,275 @@
+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2015 Charles J. Cliffe
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#pragma once
+
+#include <SoapySDR/Device.hpp>
+#include <SoapySDR/Logger.h>
+#include <SoapySDR/Types.h>
+#include <RtAudio.h>
+#include <stdexcept>
+#include <thread>
+#include <mutex>
+#include <atomic>
+#include <condition_variable>
+#include <string>
+#include <cstring>
+#include <algorithm>
+
+#ifdef USE_HAMLIB
+#include "RigThread.h"
+#endif
+
+typedef enum audioStreamFormat
+{
+    AUDIO_FORMAT_FLOAT32, AUDIO_FORMAT_INT16, AUDIO_FORMAT_INT8
+} audioStreamFormat;
+
+typedef enum chanSetup
+{
+    FORMAT_MONO_L, FORMAT_MONO_R, FORMAT_STEREO_IQ, FORMAT_STEREO_QI
+} chanSetup;
+
+#define DEFAULT_BUFFER_LENGTH 2048
+#define DEFAULT_NUM_BUFFERS 6
+
+class SoapyAudio: public SoapySDR::Device
+{
+public:
+    SoapyAudio(const SoapySDR::Kwargs &args);
+
+    ~SoapyAudio(void);
+
+    /*******************************************************************
+     * Identification API
+     ******************************************************************/
+
+    std::string getDriverKey(void) const;
+
+    std::string getHardwareKey(void) const;
+
+    SoapySDR::Kwargs getHardwareInfo(void) const;
+
+    /*******************************************************************
+     * Channels API
+     ******************************************************************/
+
+    size_t getNumChannels(const int) const;
+
+    /*******************************************************************
+     * Stream API
+     ******************************************************************/
+
+    std::vector<std::string> getStreamFormats(const int direction, const size_t channel) const;
+
+    std::string getNativeStreamFormat(const int direction, const size_t channel, double &fullScale) const;
+
+    SoapySDR::ArgInfoList getStreamArgsInfo(const int direction, const size_t channel) const;
+
+    SoapySDR::Stream *setupStream(const int direction, const std::string &format, const std::vector<size_t> &channels =
+            std::vector<size_t>(), const SoapySDR::Kwargs &args = SoapySDR::Kwargs());
+
+    void closeStream(SoapySDR::Stream *stream);
+
+    size_t getStreamMTU(SoapySDR::Stream *stream) const;
+
+    int activateStream(
+            SoapySDR::Stream *stream,
+            const int flags = 0,
+            const long long timeNs = 0,
+            const size_t numElems = 0);
+
+    int deactivateStream(SoapySDR::Stream *stream, const int flags = 0, const long long timeNs = 0);
+
+    int readStream(
+            SoapySDR::Stream *stream,
+            void * const *buffs,
+            const size_t numElems,
+            int &flags,
+            long long &timeNs,
+            const long timeoutUs = 100000);
+
+    /*******************************************************************
+     * Direct buffer access API
+     ******************************************************************/
+
+    size_t getNumDirectAccessBuffers(SoapySDR::Stream *stream);
+
+    int getDirectAccessBufferAddrs(SoapySDR::Stream *stream, const size_t handle, void **buffs);
+
+    int acquireReadBuffer(
+        SoapySDR::Stream *stream,
+        size_t &handle,
+        const void **buffs,
+        int &flags,
+        long long &timeNs,
+        const long timeoutUs = 100000);
+
+    void releaseReadBuffer(
+        SoapySDR::Stream *stream,
+        const size_t handle);
+
+    /*******************************************************************
+     * Antenna API
+     ******************************************************************/
+
+    std::vector<std::string> listAntennas(const int direction, const size_t channel) const;
+
+    void setAntenna(const int direction, const size_t channel, const std::string &name);
+
+    std::string getAntenna(const int direction, const size_t channel) const;
+
+    /*******************************************************************
+     * Frontend corrections API
+     ******************************************************************/
+
+    bool hasDCOffsetMode(const int direction, const size_t channel) const;
+
+    /*******************************************************************
+     * Gain API
+     ******************************************************************/
+
+    std::vector<std::string> listGains(const int direction, const size_t channel) const;
+
+    bool hasGainMode(const int direction, const size_t channel) const;
+
+    void setGainMode(const int direction, const size_t channel, const bool automatic);
+
+    bool getGainMode(const int direction, const size_t channel) const;
+
+    void setGain(const int direction, const size_t channel, const double value);
+
+    void setGain(const int direction, const size_t channel, const std::string &name, const double value);
+
+    double getGain(const int direction, const size_t channel, const std::string &name) const;
+
+    SoapySDR::Range getGainRange(const int direction, const size_t channel, const std::string &name) const;
+
+    /*******************************************************************
+     * Frequency API
+     ******************************************************************/
+
+    void setFrequency(
+            const int direction,
+            const size_t channel,
+            const std::string &name,
+            const double frequency,
+            const SoapySDR::Kwargs &args = SoapySDR::Kwargs());
+
+    double getFrequency(const int direction, const size_t channel, const std::string &name) const;
+
+    std::vector<std::string> listFrequencies(const int direction, const size_t channel) const;
+
+    SoapySDR::RangeList getFrequencyRange(const int direction, const size_t channel, const std::string &name) const;
+
+    SoapySDR::ArgInfoList getFrequencyArgsInfo(const int direction, const size_t channel) const;
+
+    /*******************************************************************
+     * Sample Rate API
+     ******************************************************************/
+
+    void setSampleRate(const int direction, const size_t channel, const double rate);
+
+    double getSampleRate(const int direction, const size_t channel) const;
+
+    std::vector<double> listSampleRates(const int direction, const size_t channel) const;
+
+    void setBandwidth(const int direction, const size_t channel, const double bw);
+
+    double getBandwidth(const int direction, const size_t channel) const;
+
+    std::vector<double> listBandwidths(const int direction, const size_t channel) const;
+
+    /*******************************************************************
+     * Utility
+     ******************************************************************/
+
+    chanSetup chanSetupStrToEnum(std::string chanOpt);
+
+    /*******************************************************************
+     * Settings API
+     ******************************************************************/
+
+    SoapySDR::ArgInfoList getSettingInfo(void) const;
+
+    void writeSetting(const std::string &key, const std::string &value);
+
+    std::string readSetting(const std::string &key) const;
+
+private:
+
+    //device handle
+    int deviceId;
+    RtAudio dac;
+    RtAudio::DeviceInfo devInfo;
+    RtAudio::StreamOptions opts;
+    RtAudio::StreamParameters inputParameters;
+    RtAudio::StreamParameters outputParameters;
+
+    //cached settings
+    audioStreamFormat asFormat;
+    chanSetup cSetup;
+    uint32_t sampleRate, centerFrequency;
+    unsigned int bufferLength;
+    size_t numBuffers;
+    bool agcMode, streamActive;
+    std::atomic_bool sampleRateChanged;
+    double audioGain;
+    int elementsPerSample;
+    int sampleOffset;
+    float sampleOffsetBuffer[2];
+
+public:
+    //async api usage
+    int rx_callback(void *inputBuffer, unsigned int nBufferFrames, double streamTime, RtAudioStreamStatus status);
+
+    std::mutex _buf_mutex;
+    std::condition_variable _buf_cond;
+
+    std::vector<std::vector<float> > _buffs;
+    size_t	_buf_head;
+    size_t	_buf_tail;
+    size_t	_buf_count;
+    float *_currentBuff;
+    bool _overflowEvent;
+    size_t _currentHandle;
+    size_t bufferedElems;
+    bool resetBuffer;
+
+
+#ifdef USE_HAMLIB
+public:
+    static int add_hamlib_rig(const struct rig_caps *rc, void* f);
+    static std::vector<const struct rig_caps *> rigCaps;
+    
+    void checkRigThread();
+    
+private:
+    RigThread *rigThread;
+    std::thread *t_Rig;
+    
+    rig_model_t rigModel;
+    std::string rigFile;
+    int rigSerialRate;    
+#endif
+};
diff --git a/Streaming.cpp b/Streaming.cpp
new file mode 100644
index 0000000..f6a9027
--- /dev/null
+++ b/Streaming.cpp
@@ -0,0 +1,678 @@
+/*
+ * The MIT License (MIT)
+ * 
+ * Copyright (c) 2015 Charles J. Cliffe
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "SoapyAudio.hpp"
+#include <SoapySDR/Logger.hpp>
+#include <algorithm> //min
+#include <climits> //SHRT_MAX
+#include <cstring> // memcpy
+
+
+std::vector<std::string> SoapyAudio::getStreamFormats(const int direction, const size_t channel) const {
+    std::vector<std::string> formats;
+
+    formats.push_back("CS8");
+    formats.push_back("CS16");
+    formats.push_back("CF32");
+
+    return formats;
+}
+
+std::string SoapyAudio::getNativeStreamFormat(const int direction, const size_t channel, double &fullScale) const {
+     fullScale = 65536;
+     return "CS16";
+}
+
+SoapySDR::ArgInfoList SoapyAudio::getStreamArgsInfo(const int direction, const size_t channel) const {
+    SoapySDR::ArgInfoList streamArgs;
+
+    SoapySDR::ArgInfo chanArg;
+    chanArg.key = "chan";
+    chanArg.value = "mono_l";
+    chanArg.name = "Channel Setup";
+    chanArg.description = "Input channel configuration.";
+    chanArg.type = SoapySDR::ArgInfo::STRING;
+    
+    std::vector<std::string> chanOpts;
+    std::vector<std::string> chanOptNames;
+    
+    chanOpts.push_back("mono_l");
+    chanOptNames.push_back("Mono Left");
+    chanOpts.push_back("mono_r");
+    chanOptNames.push_back("Mono Right");
+    chanOpts.push_back("stereo_iq");
+    chanOptNames.push_back("Complex L/R = I/Q");
+    chanOpts.push_back("stereo_qi");
+    chanOptNames.push_back("Complex L/R = Q/I");
+
+    chanArg.options = chanOpts;
+    chanArg.optionNames = chanOptNames;
+
+    streamArgs.push_back(chanArg);
+
+    return streamArgs;
+}
+
+/*******************************************************************
+ * Async thread work
+ ******************************************************************/
+
+
+static int _rx_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames, double streamTime, RtAudioStreamStatus status,
+        void *ctx)
+{
+    //printf("_rx_callback\n");
+    SoapyAudio *self = (SoapyAudio *)ctx;
+    return self->rx_callback(inputBuffer, nBufferFrames, streamTime, status);
+}
+
+int SoapyAudio::rx_callback(void *inputBuffer, unsigned int nBufferFrames, double streamTime, RtAudioStreamStatus status)
+{
+    std::unique_lock<std::mutex> lock(_buf_mutex);
+
+    if (sampleRateChanged.load()) {
+        return 1;
+    }
+
+    //printf("_rx_callback %d _buf_head=%d, numBuffers=%d\n", len, _buf_head, _buf_tail);
+
+    //overflow condition: the caller is not reading fast enough
+    if (_buf_count == numBuffers)
+    {
+        _overflowEvent = true;
+        return 0;
+    }
+
+    //copy into the buffer queue
+    auto &buff = _buffs[_buf_tail];
+    buff.resize(nBufferFrames * elementsPerSample);
+    std::memcpy(buff.data(), inputBuffer, nBufferFrames * elementsPerSample * sizeof(float));
+
+    //increment the tail pointer
+    _buf_tail = (_buf_tail + 1) % numBuffers;
+    _buf_count++;
+
+    //notify readStream()
+    _buf_cond.notify_one();
+    
+    return 0;
+}
+
+/*******************************************************************
+ * Stream API
+ ******************************************************************/
+
+SoapySDR::Stream *SoapyAudio::setupStream(
+        const int direction,
+        const std::string &format,
+        const std::vector<size_t> &channels,
+        const SoapySDR::Kwargs &args)
+{
+    //check the channel configuration
+    if (channels.size() > 1 or (channels.size() > 0 and channels.at(0) != 0))
+    {
+        throw std::runtime_error("setupStream invalid channel selection");
+    }
+
+    //check the format
+    if (format == "CF32")
+    {
+        SoapySDR_log(SOAPY_SDR_INFO, "Using format CF32.");
+        asFormat = AUDIO_FORMAT_FLOAT32;
+    }
+    else if (format == "CS16")
+    {
+        SoapySDR_log(SOAPY_SDR_INFO, "Using format CS16.");
+        asFormat = AUDIO_FORMAT_INT16;
+    }
+    else if (format == "CS8") {
+        SoapySDR_log(SOAPY_SDR_INFO, "Using format CS8.");
+        asFormat = AUDIO_FORMAT_INT8;
+    }
+    else
+    {
+        throw std::runtime_error(
+                "setupStream invalid format '" + format
+                        + "' -- Only CS8, CS16 and CF32 are supported by SoapyAudio module.");
+    }
+
+    if (args.count("chan") != 0)
+    {
+        std::string chanOpt = args.at("chan");        
+        cSetup = chanSetupStrToEnum(chanOpt);
+    } else {
+        cSetup = FORMAT_MONO_L;
+    }
+
+    inputParameters.deviceId = deviceId;
+    
+    switch (cSetup) {
+        case FORMAT_MONO_L:
+            inputParameters.nChannels = 1;
+            inputParameters.firstChannel = 0;
+            bufferLength = DEFAULT_BUFFER_LENGTH;
+            elementsPerSample = 1;
+            break;
+        case FORMAT_MONO_R:
+            inputParameters.nChannels = 1;
+            inputParameters.firstChannel = 1;
+            bufferLength = DEFAULT_BUFFER_LENGTH;
+            elementsPerSample = 1;
+            break;        
+        case FORMAT_STEREO_IQ:
+            inputParameters.nChannels = 2;
+            inputParameters.firstChannel = 0;
+            bufferLength = DEFAULT_BUFFER_LENGTH*2;
+            elementsPerSample = 2;
+            break;        
+        case FORMAT_STEREO_QI:
+            inputParameters.nChannels = 2;
+            inputParameters.firstChannel = 0;
+            bufferLength = DEFAULT_BUFFER_LENGTH*2;
+            elementsPerSample = 2;
+            break;
+    }
+
+    //clear async fifo counts
+    _buf_tail = 0;
+    _buf_count = 0;
+    _buf_head = 0;
+
+    //allocate buffers
+    _buffs.resize(numBuffers);
+    for (auto &buff : _buffs) buff.reserve(bufferLength);
+    for (auto &buff : _buffs) buff.resize(bufferLength);
+
+    return (SoapySDR::Stream *) this;
+}
+
+void SoapyAudio::closeStream(SoapySDR::Stream *stream)
+{
+    _buffs.clear();
+}
+
+size_t SoapyAudio::getStreamMTU(SoapySDR::Stream *stream) const
+{
+    return bufferLength / elementsPerSample;
+}
+
+int SoapyAudio::activateStream(
+        SoapySDR::Stream *stream,
+        const int flags,
+        const long long timeNs,
+        const size_t numElems)
+{
+    if (flags != 0) return SOAPY_SDR_NOT_SUPPORTED;
+    resetBuffer = true;
+    bufferedElems = 0;
+
+    try {
+#ifndef _MSC_VER
+        opts.priority = sched_get_priority_max(SCHED_FIFO);
+#endif
+        //    opts.flags = RTAUDIO_MINIMIZE_LATENCY;
+        opts.flags = RTAUDIO_SCHEDULE_REALTIME;
+
+        sampleRateChanged.store(false);
+        dac.openStream(NULL, &inputParameters, RTAUDIO_FLOAT32, sampleRate, &bufferLength, &_rx_callback, (void *) this, &opts);
+        dac.startStream();
+
+        streamActive = true;
+    } catch (RtAudioError& e) {
+        throw std::runtime_error("RtAudio init error '" + e.getMessage());
+    }
+    
+    return 0;
+}
+
+int SoapyAudio::deactivateStream(SoapySDR::Stream *stream, const int flags, const long long timeNs)
+{
+    if (flags != 0) return SOAPY_SDR_NOT_SUPPORTED;
+
+    if (dac.isStreamRunning()) {
+        dac.stopStream();
+    }
+    if (dac.isStreamOpen()) {
+        dac.closeStream();
+    }
+    
+    streamActive = false;
+    
+    return 0;
+}
+
+int SoapyAudio::readStream(
+        SoapySDR::Stream *stream,
+        void * const *buffs,
+        const size_t numElems,
+        int &flags,
+        long long &timeNs,
+        const long timeoutUs)
+{    
+    if (!dac.isStreamRunning()) {
+        return 0;
+    }
+    
+    if (sampleRateChanged.load()) {
+        if (dac.isStreamRunning()) {
+            dac.stopStream();
+        }
+        if (dac.isStreamOpen()) {
+            dac.closeStream();
+        }
+        dac.openStream(NULL, &inputParameters, RTAUDIO_FLOAT32, sampleRate, &bufferLength, &_rx_callback, (void *) this, &opts);
+        dac.startStream();
+        sampleRateChanged.store(false);
+    }
+
+    //this is the user's buffer for channel 0
+    void *buff0 = buffs[0];
+
+    //are elements left in the buffer? if not, do a new read.
+    if (bufferedElems == 0 || (sampleOffset && (bufferedElems < abs(sampleOffset))))
+    {
+        int ret = this->acquireReadBuffer(stream, _currentHandle, (const void **)&_currentBuff, flags, timeNs, timeoutUs);
+        if (ret < 0) return ret;
+        bufferedElems = ret;
+    }
+
+    size_t returnedElems = std::min(bufferedElems, numElems);
+
+    if (sampleOffset && (bufferedElems < abs(sampleOffset))) {
+        return 0;
+    }
+
+    //convert into user's buff0
+    if (sampleOffset) {
+        if (asFormat == AUDIO_FORMAT_FLOAT32)
+        {
+            float *ftarget = (float *) buff0;
+            std::complex<float> tmp;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    ftarget[i * 2] = _currentBuff[i];
+                    ftarget[i * 2 + 1] = 0;
+                }            
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        ftarget[i * 2] = sampleOffsetBuffer[i];
+                        ftarget[i * 2 + 1] = _currentBuff[i * 2 + 1]; 
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        ftarget[i * 2] = _currentBuff[(i + iStart) * 2];
+                        ftarget[i * 2 + 1] = _currentBuff[i * 2 + 1];
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        ftarget[i * 2] = _currentBuff[i * 2];
+                        ftarget[i * 2 + 1] = sampleOffsetBuffer[i];
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        ftarget[i * 2] = _currentBuff[i * 2];
+                        ftarget[i * 2 + 1] = _currentBuff[(i + iStart) * 2 + 1];
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_QI) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        ftarget[i * 2 + 1] = sampleOffsetBuffer[i];
+                        ftarget[i * 2] = _currentBuff[i * 2 + 1]; 
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        ftarget[i * 2 + 1] = _currentBuff[(i + iStart) * 2];
+                        ftarget[i * 2] = _currentBuff[i * 2 + 1];
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        ftarget[i * 2 + 1] = _currentBuff[i * 2];
+                        ftarget[i * 2] = sampleOffsetBuffer[i];
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        ftarget[i * 2 + 1] = _currentBuff[i * 2];
+                        ftarget[i * 2] = _currentBuff[(i + iStart) * 2 + 1];
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }            
+        }
+        else if (asFormat == AUDIO_FORMAT_INT16)
+        {
+            int16_t *itarget = (int16_t *) buff0;
+            std::complex<int16_t> tmp;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int16_t(_currentBuff[i] * 32767.0);
+                    itarget[i * 2 + 1] = 0;
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2] = int16_t(sampleOffsetBuffer[i] * 32767.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[(i + iStart) * 2] * 32767.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2] * 32767.0);
+                        itarget[i * 2 + 1] = int16_t(sampleOffsetBuffer[i] * 32767.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2] * 32767.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[(i + iStart) * 2 + 1] * 32767.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }
+            if (cSetup == FORMAT_STEREO_QI) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2 + 1] = int16_t(sampleOffsetBuffer[i] * 32767.0);
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[(i + iStart) * 2] * 32767.0);
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2] * 32767.0);
+                        itarget[i * 2] = int16_t(sampleOffsetBuffer[i] * 32767.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2] * 32767.0);
+                        itarget[i * 2] = int16_t(_currentBuff[(i + iStart) * 2 + 1] * 32767.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }
+        }
+        else if (asFormat == AUDIO_FORMAT_INT8)
+        {
+            int8_t *itarget = (int8_t *) buff0;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int8_t(_currentBuff[i] * 127.0);
+                    itarget[i * 2 + 1] = 0;
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2] = int16_t(sampleOffsetBuffer[i] * 127.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2 + 1] * 127.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[(i + iStart) * 2] * 127.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2 + 1] * 127.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2] * 127.0);
+                        itarget[i * 2 + 1] = int16_t(sampleOffsetBuffer[i] * 127.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2] * 127.0);
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[(i + iStart) * 2 + 1] * 127.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }
+            if (cSetup == FORMAT_STEREO_QI) {
+                if (sampleOffset > 0) {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2 + 1] = int16_t(sampleOffsetBuffer[i] * 127.0);
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2 + 1] * 127.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[(i + iStart) * 2] * 127.0);
+                        itarget[i * 2] = int16_t(_currentBuff[i * 2 + 1] * 127.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2];
+                    }                  
+                } else {
+                    size_t iStart = abs(sampleOffset);
+                    for (size_t i = 0; i < iStart; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2] * 127.0);
+                        itarget[i * 2] = int16_t(sampleOffsetBuffer[i] * 127.0);
+                    }            
+                    for (size_t i = iStart; i < returnedElems; i++) {
+                        itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2] * 127.0);
+                        itarget[i * 2] = int16_t(_currentBuff[(i + iStart) * 2 + 1] * 127.0);
+                    }            
+                    for (int i = 0; i < iStart; i++) {
+                        sampleOffsetBuffer[i] = _currentBuff[(returnedElems-iStart+i) * 2 + 1];
+                    }
+                }
+            }            
+        } 
+    } else {
+        if (asFormat == AUDIO_FORMAT_FLOAT32)
+        {
+            float *ftarget = (float *) buff0;
+            std::complex<float> tmp;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    ftarget[i * 2] = _currentBuff[i];
+                    ftarget[i * 2 + 1] = 0;
+                }            
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    ftarget[i * 2] = _currentBuff[i * 2];
+                    ftarget[i * 2 + 1] = _currentBuff[i * 2 + 1];
+                }            
+            }
+            else if (cSetup == FORMAT_STEREO_QI) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    ftarget[i * 2] = _currentBuff[i * 2 + 1];
+                    ftarget[i * 2 + 1] = _currentBuff[i * 2];
+                }            
+            }            
+        }
+        else if (asFormat == AUDIO_FORMAT_INT16)
+        {
+            int16_t *itarget = (int16_t *) buff0;
+            std::complex<int16_t> tmp;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int16_t(_currentBuff[i] * 32767.0);
+                    itarget[i * 2 + 1] = 0;
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int16_t(_currentBuff[i * 2] * 32767.0);
+                    itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_QI) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int16_t(_currentBuff[i * 2 + 1] * 32767.0);
+                    itarget[i * 2 + 1] = int16_t(_currentBuff[i * 2] * 32767.0);
+                }            
+            }            
+        }
+        else if (asFormat == AUDIO_FORMAT_INT8)
+        {
+            int8_t *itarget = (int8_t *) buff0;
+            if (cSetup == FORMAT_MONO_L || cSetup == FORMAT_MONO_R) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int8_t(_currentBuff[i] * 127.0);
+                    itarget[i * 2 + 1] = 0;
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_IQ) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int8_t(_currentBuff[i * 2] * 127.0);
+                    itarget[i * 2 + 1] = int8_t(_currentBuff[i * 2 + 1] * 127.0);
+                }
+            }
+            else if (cSetup == FORMAT_STEREO_QI) {
+                for (size_t i = 0; i < returnedElems; i++)
+                {
+                    itarget[i * 2] = int8_t(_currentBuff[i * 2 + 1] * 127.0);
+                    itarget[i * 2 + 1] = int8_t(_currentBuff[i * 2] * 127.0);
+                }            
+            }            
+        }
+    }
+    
+    //bump variables for next call into readStream
+    bufferedElems -= returnedElems;
+    _currentBuff += returnedElems * elementsPerSample;
+
+    //return number of elements written to buff0
+    if (bufferedElems != 0) flags |= SOAPY_SDR_MORE_FRAGMENTS;
+    else this->releaseReadBuffer(stream, _currentHandle);
+    return returnedElems;
+}
+
+/*******************************************************************
+ * Direct buffer access API
+ ******************************************************************/
+
+size_t SoapyAudio::getNumDirectAccessBuffers(SoapySDR::Stream *stream)
+{
+    return _buffs.size();
+}
+
+int SoapyAudio::getDirectAccessBufferAddrs(SoapySDR::Stream *stream, const size_t handle, void **buffs)
+{
+    buffs[0] = (void *)_buffs[handle].data();
+    return 0;
+}
+
+int SoapyAudio::acquireReadBuffer(
+    SoapySDR::Stream *stream,
+    size_t &handle,
+    const void **buffs,
+    int &flags,
+    long long &timeNs,
+    const long timeoutUs)
+{
+    std::unique_lock <std::mutex> lock(_buf_mutex);
+
+    //reset is issued by various settings
+    //to drain old data out of the queue
+    if (resetBuffer)
+    {
+        //drain all buffers from the fifo
+        _buf_head = (_buf_head + _buf_count) % numBuffers;
+        _buf_count = 0;
+        resetBuffer = false;
+        _overflowEvent = false;
+    }
+
+    //handle overflow from the rx callback thread
+    if (_overflowEvent)
+    {
+        //drain the old buffers from the fifo
+        _buf_head = (_buf_head + _buf_count) % numBuffers;
+        _buf_count = 0;
+        _overflowEvent = false;
+        SoapySDR::log(SOAPY_SDR_SSI, "O");
+        return SOAPY_SDR_OVERFLOW;
+    }
+
+    //wait for a buffer to become available
+    while (_buf_count == 0)
+    {
+        _buf_cond.wait_for(lock, std::chrono::microseconds(timeoutUs));
+        if (_buf_count == 0) return SOAPY_SDR_TIMEOUT;
+    }
+
+    //extract handle and buffer
+    handle = _buf_head;
+    _buf_head = (_buf_head + 1) % numBuffers;
+    buffs[0] = (void *)_buffs[handle].data();
+    flags = 0;
+
+    //return number available
+    return _buffs[handle].size() / elementsPerSample;
+}
+
+void SoapyAudio::releaseReadBuffer(
+    SoapySDR::Stream *stream,
+    const size_t handle)
+{
+    //TODO this wont handle out of order releases
+    std::unique_lock <std::mutex> lock(_buf_mutex);
+    _buf_count--;
+}
diff --git a/debian/changelog b/debian/changelog
new file mode 100644
index 0000000..f7e4023
--- /dev/null
+++ b/debian/changelog
@@ -0,0 +1,5 @@
+soapyaudio (0.0.0) unstable; urgency=low
+
+  * pending
+
+ -- Josh Blum <josh at pothosware.com>  Sun, 03 Jan 2016 13:18:35 -0800
diff --git a/debian/compat b/debian/compat
new file mode 100644
index 0000000..ec63514
--- /dev/null
+++ b/debian/compat
@@ -0,0 +1 @@
+9
diff --git a/debian/control b/debian/control
new file mode 100644
index 0000000..149e883
--- /dev/null
+++ b/debian/control
@@ -0,0 +1,22 @@
+Source: soapyaudio
+Section: libs
+Priority: optional
+Maintainer: Charles J. Cliffe <cj at cubicproductions.com>
+Uploaders: Josh Blum <josh at pothosware.com>
+Build-Depends:
+    debhelper (>= 9.0.0),
+    cmake,
+    libhamlib-dev,
+    libsoapysdr-dev
+Standards-Version: 3.9.5
+Homepage: https://github.com/pothosware/SoapyAudio/wiki
+Vcs-Git: https://github.com/pothosware/SoapyAudio.git
+Vcs-Browser: https://github.com/pothosware/SoapyAudio
+
+Package: soapysdr-audio
+Section: libs
+Architecture: any
+Pre-Depends: ${misc:Pre-Depends}
+Depends: ${shlibs:Depends}, ${misc:Depends}
+Description: Soapy Audio - Audio device support for Soapy SDR.
+ A Soapy module that supports Audio devices within the Soapy API.
diff --git a/debian/copyright b/debian/copyright
new file mode 100644
index 0000000..c561c81
--- /dev/null
+++ b/debian/copyright
@@ -0,0 +1,50 @@
+Format: http://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
+Upstream-Name: soapyaudio
+Source: https://github.com/pothosware/SoapyAudio/wiki
+
+Files: *
+Copyright: Copyright (c) 2015 Charles J. Cliffe
+License: MIT
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+ .
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+ .
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+
+Files: RtAudio/*
+Copyright: Copyright (c) 2001-2014 Gary P. Scavone
+License: The RtAudio license is similar to the MIT License.
+ Permission is hereby granted, free of charge, to any person
+ obtaining a copy of this software and associated documentation files
+ (the "Software"), to deal in the Software without restriction,
+ including without limitation the rights to use, copy, modify, merge,
+ publish, distribute, sublicense, and/or sell copies of the Software,
+ and to permit persons to whom the Software is furnished to do so,
+ subject to the following conditions:
+ .
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+ .
+ Any person wishing to distribute modifications to the Software is
+ asked to send the modifications to the original developer so that
+ they can be incorporated into the canonical version.  This is,
+ however, not a binding provision of this license.
+ .
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+ ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
diff --git a/debian/docs b/debian/docs
new file mode 100644
index 0000000..b43bf86
--- /dev/null
+++ b/debian/docs
@@ -0,0 +1 @@
+README.md
diff --git a/debian/rules b/debian/rules
new file mode 100644
index 0000000..a904ad9
--- /dev/null
+++ b/debian/rules
@@ -0,0 +1,20 @@
+#!/usr/bin/make -f
+# -*- makefile -*-
+
+DEB_HOST_MULTIARCH ?= $(shell dpkg-architecture -qDEB_HOST_MULTIARCH)
+export DEB_HOST_MULTIARCH
+
+# Uncomment this to turn on verbose mode.
+#export DH_VERBOSE=1
+
+# This has to be exported to make some magic below work.
+export DH_OPTIONS
+
+
+%:
+	dh $@ --buildsystem=cmake --parallel
+
+override_dh_auto_configure:
+	dh_auto_configure -- \
+		-DLIB_SUFFIX="/$(DEB_HOST_MULTIARCH)" \
+		-DUSE_HAMLIB=ON
diff --git a/debian/source/format b/debian/source/format
new file mode 100644
index 0000000..163aaf8
--- /dev/null
+++ b/debian/source/format
@@ -0,0 +1 @@
+3.0 (quilt)

-- 
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/pkg-hamradio/soapyaudio.git



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