Description

Lziprecover is a data recovery tool and decompressor for files in the
lzip compressed data format (.lz) able to repair slightly damaged files,
recover badly damaged files from two or more copies, extract undamaged
members from multi-member files, decompress files and test integrity of
files.

Lziprecover is able to recover or decompress files produced by any of
the compressors in the lzip family; lzip, plzip, minilzip/lzlib, clzip
and pdlzip. This recovery capability contributes to make the lzip format
one of the best options for long-term data archiving.

When recovering data, lziprecover takes as arguments the names of the
damaged files and writes zero or more recovered files depending on the
operation selected and whether the recovery succeeded or not. The
damaged files themselves are never modified.

When decompressing or testing file integrity, lziprecover behaves like
lzip or lunzip.

If the files are too damaged for lziprecover to repair them, data from
damaged members can be partially recovered writing it to stdout.

To give you an idea of its possibilities, when merging two copies each
of them with one damaged area affecting 1 percent of the copy, the
probability of obtaining a correct file is about 98 percent. With three
such copies the probability rises to 99.97 percent. For large files with
small errors, the probability approaches 100 percent even with only two
copies.

If the cause of file corruption is damaged media, the combination
GNU ddrescue + lziprecover is the best option for recovering data from
multiple damaged copies.