The gzip Recovery Toolkit attempts to automate the recovery of data from corrupted gzip files (including tarballs) through a program called gzrecover. This package is still very experimental at this point.
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This release contains two principal updates.
First, a change was made in the read strategy in
gzrecover. Previously, the corrupted gzip data
extractor program relied on mmap(2) to read files.
This has been changed to a buffered read strategy
which should allow support for any sized file as
well as platforms that don't allow files to be
memory mapped. Files sizes up to 168GB have been
tested. Second, the license on gzrecover has been
switched from the zlib license (a BSD variant) to
the GPL.