Re: growisoimage burnt a CD that cannot be mounted unless specify iso9660 as filesystem

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

> If growisofs did it right, something must have done it wrong,

The last genisoimage created session is not to the taste of both,
Windows and Linux. They just react differently on the disappointment
that there seem to be no valid UDF metadata.


> almustafa@orphalese:~$ file /dev/sr1
> /dev/sr1: block special

My proposal was too optimistic.

You could try 
  file -s /dev/sr1

> almustafa@orphalese:~$ dd if=/dev/sr1 of=/tmp/test.iso bs=1048576 count=1
> almustafa@orphalese:~$ file /tmp/test.iso 
> /tmp/test.iso: # ISO 9660 CD-ROM filesystem data 'K3b data project'
> Note that the message 'K3b burnt it' must be one of the previous session.

This would probably come from the first session. After all you copied
only the first MB of the media to the file.
Eventually file had no chance to see the UDF signature. If i remember right,
there is an UDF "anchor" near the end of the image.

A pragmatic approach would be to look for Standard Identifiers of the
Volume Structure Descriptors as of ECMA-167.
That would be strings "BEA01" and "TEA01" at byte offset 1 to 5 of
2 kB blocks in the range of block 16 to approx. block 24.

Actually an image produced by
  genisoimage -udf -o /u/test/genisoimage.udf my_test_file
bears:
Block | Content      | Meaning
------|--------------|----------------------------------  
 16   | \001 "CD001" | ECMA-119/ISO 9660 primary volume descriptor
 17   | \377 "CD001" | ECMA-119/ISO 9660 terminating descriptor
 18   | \000 "BEA01" | ECMA-167/UDF Beginning Extended Area Descriptor
 19   | \000 "TEA01" | ECMA-167/UDF Terminating Extended Area Descriptor


Have a nice day :)

Thomas