lzip is a free,

command-line A command-line interpreter or command-line processor uses a command-line interface (CLI) to receive commands from a user in the form of lines of text. This provides a means of setting parameters for the environment, invoking executables and pro ...

tool for the compression of data; it employs the

Lempel–Ziv–Markov chain algorithm The Lempel–Ziv–Markov chain algorithm (LZMA) is an algorithm used to perform lossless data compression. It has been under development since either 1996 or 1998 by Igor Pavlov and was first used in the 7z format of the 7-Zip archiver. This ...

(LZMA) with a user interface that is familiar to users of usual Unix compression tools, such as

gzip gzip is a file format and a software application used for file compression and decompression. The program was created by Jean-loup Gailly and Mark Adler as a free software replacement for the compress program used in early Unix systems, and i ...

and bzip2. Like

and bzip2,

concatenation In formal language theory and computer programming, string concatenation is the operation of joining character strings end-to-end. For example, the concatenation of "snow" and "ball" is "snowball". In certain formalisations of concatenat ...

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 Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bi ...

cpio cpio is a general file archiver utility and its associated file format. It is primarily installed on Unix-like computer operating systems. The software utility was originally intended as a tape archiving program as part of the Programmer's Wor ...

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, an ...

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 A filename extension, file name extension or file extension is a suffix to the name of a computer file (e.g., .txt, .docx, .md). The extension indicates a characteristic of the file contents or its intended use. A filename extension is typically ...

, and the data is described by the media type application/lzip. The lzip suite of programs was written in

C++ C++ (pronounced "C plus plus") is a high-level general-purpose programming language created by Danish computer scientist Bjarne Stroustrup as an extension of the C programming language, or "C with Classes". The language has expanded significan ...

and C by Antonio Diaz Diaz and is being distributed as

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...

under the terms of version 2 or later of the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general ...

(GPL).

History

7-Zip 7-Zip is a free and open-source file archiver, a utility used to place groups of files within compressed containers known as "archives". It is developed by Igor Pavlov and was first released in 1999. 7-Zip has its own archive format called 7z, ...

was released in 2000; a tool employing LZMA first became available on

Unix-like A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-li ...

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 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 XZ Utils (previously LZMA Utils) is a set of free software command-line lossless data compressors, including the programs lzma and xz, for Unix-like operating systems and, from version 5.0 onwards, Microsoft Windows. For compression/decompressio ...

Features

File integrity

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). 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 A checksum is a small-sized block of data derived from another block of digital data for the purpose of detecting errors that may have been introduced during its transmission or storage. By themselves, checksums are often used to verify data ...

for each compressed stream; this is used in combination with the lziprecover program to detect and reconstruct damaged data. This recovery tool can merge multiple copies of an archive where each copy may have damage in a different part of the file.

Parallelism

lzip has two parallel interfaces provided in the default distribution. * compresses any file in a parallel way. Using it with is insufficient, since the conventional program needs the entire stream before a file to locate it for decompression, resulting in non-parallel extraction. * combines and into a parallel archiver much like modern archivers like RAR or 7-Zip. The

solid compression In computing, solid compression is a method for data compression of multiple files, wherein all the uncompressed files are concatenated and treated as a single data block. Such an archive is called a solid archive. It is used natively in the 7z a ...

blocks align with file boundaries, so extracting a file only requires decompressing that particular member block.

Adoption

Availability

In popular Linux distributions, lzip can usually be installed from official package repositories. Cygwin offers lzip as a maintained optional package (Archive category of its setup installer), and its GNU tar utility program has support for .lz archives (with --lzip option for creation).

MinGW-w64 Mingw-w64 is a free and open source software development environment to create (cross-compile) Microsoft Windows PE applications. It was forked in 2005–2010 from MinGW (''Minimalist GNU for Windows''). Mingw-w64 includes a port of the GNU ...

distributes lzip through a maintained package in

MSYS2 Mingw-w64 is a free and open source software development environment to create ( cross-compile) Microsoft Windows PE applications. It was forked in 2005–2010 from MinGW (''Minimalist GNU for Windows''). Mingw-w64 includes a port of the GNU C ...

(pacman -S lzip). Lzip is also available for Android in a terminal-interface which was ported by Master-Console Inc.

Support

* The

GNU Autotools The GNU Autotools, also known as the GNU Build System, is a suite of programming tools designed to assist in making source code packages portable to many Unix-like systems. It can be difficult to make a software program portable: the C compiler ...

support lzip. Adding dist-lzip to AM_INIT_AUTOMAKE will build lzip-ed

balls. * Versions 1.23 and newer of GNU tar support using lzip to handle compressed files transparently. * GNOME's archiving tool, '' Archive Manager'', supports lzip files.

Application

* The Linux distribution '' Dragora GNU/Linux-Libre'' employs lzip for its software packages. * Lzip is used to distribute the Time Zone Database from IANA, and the GNU version of the Linux kernel. * The

European Parliament The European Parliament (EP) is one of the legislative bodies of the European Union and one of its seven institutions. Together with the Council of the European Union (known as the Council and informally as the Council of Ministers), it adopts ...

publishes complete dumps of its database in JSON format compressed with lzip. * Lzip is used in NASA's

Planetary Data System The Planetary Data System (PDS) is a distributed data system that NASA uses to archive data collected by Solar System missions. The PDS is an active archive that makes available well documented, peer reviewed planetary data to the research communi ...

(PDS).

References

External links

*
Lzip format specification

Lzip format specification at IETF
{{Archive formats Free data compression software