If you open tar and gzip with IPC::Open3 or IPC::Run, then you'll be able to capture and use ALL 3 STD* pipes. I might reconsider using the Perl modules, though. While you might be able to mail yourself the STDERR from the failed tar, it might not always be obvious what happened. With the perl modules, this is less so. You should at least pick up on $? and turn on verbose mode on the tar and gzip.

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