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Diffstat (limited to 'README')
| -rw-r--r-- | README | 32 |
1 files changed, 27 insertions, 5 deletions
@@ -5,9 +5,30 @@ small size makes it well suited for embedded devices or software installers that need to decompress files but do not need compression capabilities. Lunzip is fully compatible with lzip-1.4 or newer. -The lzip file format is designed for long-term data archiving. It is -clean, provides very safe 4 factor integrity checking, and is backed by -the recovery capabilities of lziprecover. +The lzip file format is designed for data sharing and long-term +archiving, taking into account both data integrity and decoder +availability: + + * The lzip format provides very safe integrity checking and some data + recovery means. The lziprecover program can repair bit-flip errors + (one of the most common forms of data corruption) in lzip files, + and provides data recovery capabilities, including error-checked + merging of damaged copies of a file. + + * The lzip format is as simple as possible (but not simpler). The + lzip manual provides the code of a simple decompressor along with a + detailed explanation of how it works, so that with the only help of + the lzip manual it would be possible for a digital archaeologist to + extract the data from a lzip file long after quantum computers + eventually render LZMA obsolete. + + * Additionally the lzip reference implementation is copylefted, which + guarantees that it will remain free forever. + +A nice feature of the lzip format is that a corrupt byte is easier to +repair the nearer it is from the beginning of the file. Therefore, with +the help of lziprecover, losing an entire archive just because of a +corrupt byte near the beginning is a thing of the past. Lunzip uses the same well-defined exit status values used by lzip and bzip2, which makes it safer than decompressors returning ambiguous @@ -23,7 +44,8 @@ smaller the output buffer size used in relation to the dictionary size, the more accesses to disk are needed and the slower the decompression is. This "low memory" mode only works when decompressing to a regular file and is intended for systems without enough memory (RAM + swap) to -keep the whole dictionary at once. +keep the whole dictionary at once. It has been tested on a laptop with a +486 processor and 4MiB of RAM. The amount of memory required by lunzip to decompress a file is about 46 kB larger than the dictionary size used to compress that file, unless @@ -61,7 +83,7 @@ range encoding), Igor Pavlov (for putting all the above together in LZMA), and Julian Seward (for bzip2's CLI). -Copyright (C) 2010, 2011, 2012, 2013, 2014 Antonio Diaz Diaz. +Copyright (C) 2010-2015 Antonio Diaz Diaz. This file is free documentation: you have unlimited permission to copy, distribute and modify it. |