Before Trevor suggests it, there is *always* a Perl module for it:

Archive::Tar

Which let's you rename the files inside a tarbal:

$tar->rename( $old_file_name, $new_file_name )

see: http://search.cpan.org/~bingos/Archive-Tar-2.26/lib/Archive/Tar.pm#$tar->list_files(_[\@properties]_)

-Brad



On 10/12/2017 1:10 PM, Kevin McGregor wrote:
Is there a way to untar a tar archive to stdout and use that output to recreate the archive by piping it back into tar? GNU tar has a transform option to change the file names. 

Sent from my iPhone

On Oct 12, 2017, at 10:42, Adam Thompson <athompso@athompso.net> wrote:

On 2017-10-12 08:59, Kevin McGregor wrote:

Given a gzipped cpio archive (12 GB!) with files in it like:
 
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/CILICEXP.xml
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/CILTSVTP.xml
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/C1LOOUPP.xml
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/CILTTRAL.xml
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/CILCSSPL.xml
wwdsvdccb101/root/data/ccb/ccbx/splapp/servers/myserver/tmp/.appmergegen_1347913274622/SPLWeb.ear/h7y1ba/data/xml/CILTCLGP.xml
 
How can I change the first component of the path to something else without unpacking the entire archive to disk first? Obviously I'll still have to un-gzip and de-cpio the whole 12GB while processing; I just don't want to put the whole thing on disk while I'm changing the path.
 
Any ideas?