Update: Reading/Writing to /dev/port using Mono.Posix.Syscall.open, lseek, read, write did the trick. Is there any better way of doing this operation? -- View this message in context: http://mono.1490590.n4.nabble.com/Mono-Linux-Direct-IO-tp4663179p4663182.html Sent from the Debian Mono mailing list archive at Nabble.com.