From: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Date: Thu, 22 Sep 2005 19:13:26 GMT
Subject: Re: cg-export incompatible with older versions of GNU tar
Message-ID: <43330256.7000505@lsrfire.ath.cx>
In-Reply-To: <20050922124338.246D535267B@atlas.denx.de>

Wolfgang Denk wrote:
> In message <20050922120841.GH21019@pasky.or.cz> you wrote:
> 
>>>-> tar jxf foo.tar.bz2 
>>>tar: pax_global_header: Unknown file type 'g', extracted as normal file
>>>...
> 
> 
>>It is unclear if the tar actually extracts the archive or not, though.
>>Does it just complain with those warnings, or are they fatal errors?
> 
> 
> In this case extraction went fine, except for the warning message.

And you get an extra file, pax_global_header, containing the commit ID
of the archive's contents.

> I had other error reports from customers befroe, where unpacking  the
> tarballs failed - instead of the origianl source tree just a bunch of
> *.data  and  *.paxheader  were created; error messages in these cases
> looked like this:
> 
> tar: pax_global_header: Unknown file type 'g', extracted as normal file
> tar: ea1efd7f213469bcde030e00ac9f89ed16256869.paxheader: Unknown file type 'x', extracted as normal file

[snip]

This happens when you have pathes inside the tar file that are longer
than 100 characters.  Is this taken from a real-world project or is it
just some test?

All your files with pathes longer than 100 chars will be extracted as
<SHA1>.data, with an accompanying <SHA1>.paxheader file.  The latter
contains the real filename.  You could then repair the mess by renaming
them manually or write a script that does it for you.  Or you could
simply update tar. :-)

Lately I noticed that the tar version used by the BSDs also doesn't
understand Pax extended headers.  I guess they're not that popular a
feature.

> [But this was with older versions of git / cogito, so I'm not sure if
> this still applies.]

Nothing has changed in this respect, basicly since git-tar-tree went in.

René