It would also be interesting to know which version of tar you are using.

tar --version will tell you.

& btw, tar will print out a listing or table of the files in an
archive by using this command:-

tar -tvf archive.tar

no need to go futzing with a gooey program like ark.



On 4/11/08, Volker Kuhlmann <[EMAIL PROTECTED]> wrote:
> On Fri 11 Apr 2008 08:08:49 NZST +1200, Steve Holdoway wrote:
>
> > > The gzip and bzip2 (de)compressions are built into tar itself. If this
> >
> > Are you sure? They never used to be. You always used to have to install
> > bzip2 before the j option would work.
>
> A decade ago when I compiled gnu stuff for slowlaris (slow to catch up with
> decent shell programs) zlib o.e. was optionally needed for compression
> support. bzip2 came later. Seeing that tar is a pretty low-level tool which
> system operation to some extend depends on, it makes sense not to add a
> reliance on being able to exec other binaries. But here's the pudding:
>
> touch file
> strace -e trace=process tar -cjf bla.tar.bz2 file
>
> No exec other than for /bin/tar.
> No other binary program file access with trace=file either.
>
> On my tar at least the compressions are built in, I guess it's possible that
> other distros do it differently.
>
> It still doesn't explain the truncated tar output - if rudiments of a
> tar directory listing exist, the compression must have gone at least that
> far.
>
> Other thought: check whether app-armor etc kicks in from/for cron (check
> syslog).
>
> Roger, please write a script which produces no output and does your backup.
> You want to add at the top:
>
> exec >/tmp/stdout.$$
> exec 2>/tmp/stderr.$$
> ulimit -a
> env
>
> Run from shell. Verify there's no output! Then run from cron. Compare files,
> esp the stderr. No matter whether you found a workaround, I'd want to know
> why it fails.
>
> Volker
>
> --
> Volker Kuhlmann                       is list0570 with the domain in header
> http://volker.dnsalias.net/   Please do not CC list postings to me.
>


-- 
Sincerely etc.
Christopher Sawtell

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