Re: AM_INIT_AUTOMAKE([1.9 tar-ustar]) and GNU TAR problems

[Ralf Wildenhues]

Hi Kent,

* Kent Boortz wrote on Mon, Nov 09, 2009 at 04:30:29PM CET:
> My real question is, how can I specify what TAR to use in "make dist",
> and avoid GNU TAR for my packaging, when 'tar-ustar' is specified to
> automake?

If you have a configure test which will find a good tar program for you,
then invoke this test before AM_INIT_AUTOMAKE and store the result in
$am_cv_prog_tar_ustar.

If you don't have a configure test, then you can still teach your users
to override the Automake default setting with
  ./configure am_cv_prog_tar_ustar=...

[...]
> The problem is, even with GNU TAR 1.22 the format it produces is not
> fully compatible with most other USTAR TAR implementations I have
> tried. These I found could not unpack the test TAR I produced with
> GNU TAR and the flag "--format=ustar"
> 
>   AIX 5.3
>   HP-UX 11.11, 11.23, 11.31
>   Solaris 8, 9, 10, 11
>   SCO OpenServer 6

If it is possible to generate a broken/unextractable archive on one
system, then we could start thinking about adding a configure test to
automake/m4/tar.m4.  But regardless of that, may I ask you to report
this issue to bug-tar at gnu.org if you haven't already?

Thanks,
Ralf

> I tried the small snippet below. Then distributed the resulting TAR to
> the AIX, HP-UX and other hosts, and tried unpack it there with the TAR
> that came with that operating system. If I packed with GNU TAR they
> could not unpack it correctly (only the top directory was created), if
> packed with Solaris TAR all could unpack it, even GNU TAR
> 
>   # I try be as nice as I can, 98 + 20 + 77 should be within USTAR
>   # format limits even if one or two chars are wasted on '\0' or the
>   # '/' delimiter
>   
> a=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
>   b=bbbbbbbbbbbbbbbbbbbb
>   
> c=ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
> 
>   rm -fr $a
>   mkdir -p $a/$b
>   touch $a/$b/$c
> 
>   # GNU TAR
>   gtar --format=ustar -cf foo.tar $a
>   # Solaris TAR
>   #/usr/bin/tar -cf foo.tar $a