Re: [Libcdio-help] Copying a file from a DVD to local storage

[Kamil Ignacak]

On 27.08.2010 23:33, Rocky Bernstein wrote:
> On Wed, Aug 25, 2010 at 4:18 AM, Syed Ahsan <address@hidden
> <mailto:address@hidden>> wrote:
>     So,
>     1) Does libcdio works for DVDs ? .. as some codes which provide info
>     for the
>     disk, like track.c and even my code (for some cases) was working for
>     DVDs.
>
>
> Somewhat, and not really, and no depending on what aspect of DVD's you
> want. If the DVD has an ISO 9660 file systems (which it can have, but
> often doesn't) then I think somewhat.

You need to be careful when reading ISO 9660 file systems from DVDs.
If the file system is larger than 4GB, libiso9660 can't handle it 
properly. One of library functions (iso9660_iso_seek_read()?) uses byte 
offset parameter, and that offset is wrapped back to zero when it 
reaches 2^32 bytes. I have tested this on my 64-bit machine, header in 
/usr/include/cdio/iso9660.h says "$Id: iso9660.h,v 1.102 2008/07/16 
00:28:54 rocky Exp $".

Reading large ISO 9660 file systems (over 4GB) results in a file that 
has ISO header at the beginning of file, and a copy of it right after 
(2^32 - 1)th byte.

Kind regards,
Kamil Ignacak