Re: symlinks warnings for joliet when mkisofs

[Thomas Schmitt]

Hi,

Karl Berry wrote:
> I am now getting warnings about symlinks:
> libisofs: WARNING : Cannot add /archive/12many.doc.tar.xz to Joliet tree.
> Symlinks can only be added to a Rock Ridge tree.
>
> I think there were no warnings with earlier versions.

That's an old message for an old reason. As a "WARNING" it is not overly
bad. If you mount the ISO on the Linux kernel by
  mount -o norock
or on MS-Windows, then the mounted tree will not show the symbolic links.
If the links are important and MS-Windows is a goal, then there is a
substantial problem, of course. :))

A test with the oldest GNU xorriso version:

  $ xorriso-0.4.9 -no_rc -as mkisofs -o /dev/null -J /home/test/softlinks
  ...
  libisofs: WARNING : Can't add /link1 to Joliet tree. Symlinks can only be 
added to a Rock Ridget tree.
  ...
  Writing to 'stdio:/dev/null' completed successfully.

  $ xorriso-0.4.9 -no_rc -version
  GNU xorriso 0.4.9 : RockRidge filesystem manipulator, libburnia project.
  ...
  Version timestamp :  2010.02.19.172125
  ...

The comands -no_rc are needed only because my local xorriso startup files
contain some commands which are more modern than 2010.

The same happens with xorriso-0.1.2 of 2008.03.12.100001.


Maybe you added option -J since the runs without warnings ?
Or there were no symbolic links in the past ?

Google ... https://www.tug.org/texcollection/ ...

  $ wget 
https://ftp.tu-chemnitz.de/pub/tug/historic/systems/texlive/2019/texlive2019-20190410.iso
  ... [6.8 MB/s] ...


> (I don't know the
> version I used to create the TeX Live images last year -- is it recorded
> in the iso somewhere?

Depends on whether the default setting of Preparer Id was overridden.
By default, the xorriso version is recorded there. Overriding is done
by -as mkisofs option -p or by command -preparer_id.

Preparer Id is part of the ISO 9660 Primary Volume Descriptor, which is
kidnof the superblock. xorriso displays the various PVD ids by command
-pvd_info:

  $ xorriso -indev debian-10.6.0-amd64-netinst.iso -pvd_info
  ...
  Preparer Id  : XORRISO-1.5.0 2018.09.15.133001, LIBISOBURN-1.5.0, 
LIBISOFS-1.5.0, LIBBURN-1.5.0
  ...

> Whatever was current about a year ago, anyway.

That would be 1.5.0 (2018.09.15.133001) or 1.5.2 (2019.10.26.180001).


> So I presume the only answer is not to create Joliet, i.e., no -J?

Depends on why -J was used on the first hand.
If it shall display on MS-Windows the directories and data files with
authentic names up to 64 characters length, then it is ok.
If it shall give on MS-Windows the same experience as on Un*x, then the
use of symbolic links is a mistake.

The download of texlive2019-20190410.iso is complete. Let's have a look:

  $ xorriso -indev texlive2019-20190410.iso -pvd_info -toc \
            -find / -type l -exec lsdl --
  ...
  Preparer Id  : XORRISO-1.5.0 2018.09.15.133001, LIBISOBURN-1.5.0, 
LIBISOFS-1.5.0, LIBBURN-1.5.0
  ...
  Creation Time: 2019041015584200
  ...
  ISO offers   : Rock_Ridge Joliet
  ISO loaded   : Rock_Ridge
  ...
  ... [no -find -exec lsdl output of symbolic links to see] ...

So there was option -J used, but no symbolic links were put into the ISO.

If i do the same with a Debian netinst ISO, which is known to have symlinks,
then i see them at the end of the run's output:
  ...
  lr-xr-xr-x    1 0        0               0 Sep 26 12:18 '/debian' -> '.'
  lr-xr-xr-x    1 0        0               0 Sep 26 12:18 '/dists/stable' -> 
'buster'
  ...
I guess you will see such link lines if you inspect the newest Tex Live
by either xorriso or by mounting it with default -o (i.e. no norock).


Have a nice day :)

Thomas