Lzip

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lzip
Lzip.png
Original author(s) Antonio Diaz Diaz
Developer(s) Antonio Diaz Diaz
Initial release 2008 (2008)
Stable release 1.15 / 1 October 2013; 14 months ago (2013-10-01)
Preview release 1.6-pre1 / 7 October 2013; 14 months ago (2013-10-07)
Written in C++
Operating system Unix-like, Windows
License GPL (Free software)
Website lzip.nongnu.org/lzip.html
lzip
Filename extension .lz
Internet media type application/x-lzip
Magic number 0x4C, 0x5A, 0x49, 0x50
Developed by Antonio Diaz
Type of format Data compression
Open format? Yes

lzip is a free, command-line tool for the compression of data; it employs the Lempel–Ziv–Markov chain algorithm (LZMA) with a user interface that is familiar to users of usual Unix compression tools, such as gzip and bzip2.

Like gzip and bzip2, concatenation is supported to compress multiple files, but the convention is to bundle a file that is an archive itself, such as those created by the tar or cpio Unix programs. Lzip can split the output for the creation of multivolume archives.

The file that is produced by lzip is usually given .lz as its filename extension, and the data is described by the MIME type application/x-lzip.

The lzip suite of programs was written in C++ and C by Antonio Diaz Diaz and is being distributed as free software under the terms of version 3 or later of the GNU General Public License (GPL).

File integrity[edit]

lzip is capable of creating archives with independently decompressible data sections called a "multimember archive" (as well as split output for the creation of multivolume archives).[1] For example, if the underlying file is a tar archive, this can allow extracting any undamaged files, even if other parts of the archive are damaged.

As for the file format, special emphasis has been put on enabling integrity checks by means of an integrated 32-bit checksum for each compressed stream;[2] this is used in combination with the lziprecover program to detect and reconstruct damaged data.[1]

The recovery tool can merge multiple copies of an archive where each copy may have damage in a different part of the file.

History[edit]

7-Zip was released in 2000; a tool employing LZMA first became available on Unix-like operating systems in 2004 when a port of the command line version of 7-Zip (p7zip) was released. In the same year, the LZMA SDK became available, which included the program called “lzma_alone”; less than a year later, Lasse Collin released LZMA Utils, which at first only consisted of a set of wrapper scripts implementing a gzip-like interface to lzma_alone. In 2008, Antonio Diaz Diaz released lzip, which uses a proper container format with checksums and magic numbers instead of the raw LZMA data stream, providing a complete Unix-style solution for using LZMA. Nevertheless, LZMA Utils was extended to have similar features and then renamed to XZ Utils.[3]

Adoption[edit]

The Linux distribution Dragora GNU/Linux employs lzip for its software packages.

In popular Linux distributions, lzip can usually be installed from official package repositories.[4][5][6]

GNOME's archiving tool, File Roller, supports lzip files.

The GNU Autotools support lzip. Adding dist-lzip to AM_INIT_AUTOMAKE will build lzip-ed tarballs.[7]

The lzip suite of programs is directly competing with XZ Utils.

See also[edit]

References[edit]

  1. ^ a b Antonio Diaz Diaz (2011-12-20). "Lzip Manual: Introduction". Lzip can produce multimember files and safely recover, with lziprecover, the undamaged members in case of file damage. Lzip can also split the compressed output in volumes of a given size, even when reading from standard input. This allows the direct creation of multivolume compressed tar archives. 
  2. ^ Antonio Diaz Diaz (2011-12-20). "Lzip Manual: Introduction". As a self-check for your protection, lzip stores in the member trailer the 32-bit CRC of the original data and the size of the original data, to make sure that the decompressed version of the data is identical to the original. 
  3. ^ Brian Lindholm (Mai 2009), "New Options in the World of File Compression" (in German), Linux Gazette (162), http://linuxgazette.net/162/lindholm.html. Retrieved 2011-01-07
  4. ^ http://packages.debian.org/lzip
  5. ^ https://admin.fedoraproject.org/pkgdb/acls/name/lzip
  6. ^ http://software.opensuse.org/search?q=lzip
  7. ^ https://www.gnu.org/software/automake/manual/html_node/List-of-Automake-options.html

External links[edit]