[Debburn-devel] Mysterious multisession failure

[Barry Kauler]

I am one of the developers of the Puppy Linux distro.

Puppy supports saving a session back to CD or DVD, or rather it used to.
I haven't tested this for awhile, tried it today and got an error.
First I tried with a DVD-R, then a CD-R.

So, I have attempted to narrow-down the error, and I have reduced to
these very simple steps. The following is reproducable, but the same
steps used to work. At first I was using cdrkit 1.1.6, so I upgraded to
1.1.9, but still the same error.

Of course, in the steps below, for cdrkit substitute 'genisoimage' for
'mkisofs', and 'wodim' for 'cdrecord'. I use cdrkit with the old names
as symlinks.

I have a 'build' directory with 97MB of files in it, all within the 8.3 format:

# ls build
boot.msg  initrd.gz     isolinux.cfg  pup4-416.sfs
help.msg  isolinux.bin  logo.16       vmlinuz

# mkisofs -D -R -o cd-puppy.iso -b isolinux.bin -c boot.cat
-no-emul-boot -boot-load-size 4 -boot-info-table ./build/

Burn to cd-r, multi-session:

# cdrecord -multi -tao -pad -data -eject -v speed=10 dev=/dev/sr0 cd-puppy.iso

Now, instead of burning an actual session to the cd, I will just use
the '-print-size' option, which suffices to report the error...

# SECT=`cdrecord -msinfo dev=/dev/sr0 | grep '^[0-9]*.[0-9]'`
# export SECT

# mkisofs -print-size -D -R -C $SECT -M /dev/sr0 -quiet -new-dir-mode
0755 -graft-points 2009-07-15=/root/nothing

Where /root/nothing is a directory with just one zero-byte file inside it.
But, get the same error whatever directory I specify.

...the above is supposed the return the size to be written, instead it
aborts with this:

Rock Ridge signatures found
genisoimage: Error: '(null)' and '/..' have the same ISO9660 name ''.
genisoimage: Error: '(null)' and '/..' have the same Rock Ridge name '..'.
Unable to sort directory

The above is incredibly simple, so why the failure? Note, I have '-D'
as some of our sessions may be too deep. It has never been a
problem using '-D' before. I am totally stuck, need urgent help!

Quite likely one of you cdrkit developer guys will recognise right off what
the problem is ...at least I'm hoping so!

Regards,
Barry Kauler
puppylinux.com