ptardiff is a small program that diffs an extracted archive against an unextracted one, using the perl module Archive::Tar. This effectively lets you view changes made to an archives contents. Provide the progam with an ARCHIVE_FILE and it will look up all the files with in the archive, scan the current working directory for a file with the name and diff it against the contents of the archive.
ptardiff ARCHIVE_FILE ptardiff -h $ tar -xzf Acme-Buffy-1.3.tar.gz $ vi Acme-Buffy-1.3/README [...] $ ptardiff Acme-Buffy-1.3.tar.gz > README.patch
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