Archiving and compression - ArchWiki

# Archiving and compression

From ArchWiki

The traditional Unix archiving and compression tools are separated according to the Unix philosophy:

- A file archiver combines several files into one archive file, e.g. tar.
- A compression tool compresses and decompresses data, e.g. gzip.

These tools are often used in sequence by firstly creating an archive file and then compressing it.

Of course there are also tools that do both, which tend to additionally offer encryption, error detection and recovery.

## Archiving only

Name | Package | Manuals | Description
--- | --- | --- | ---
GNU tar | tar | tar(1), info | Core utility for manipulating the ubiquitous tar archives (tarballs), which are used by pacman and the AUR.
libarchive | libarchive | bsdtar(1) bsdcpio(1) | Implementation of tar and cpio that also offers a library. Used by pacman and mkinitcpio.
ar | binutils | ar(1) | Legacy Unix archiver before tar. Today only used for creating static library files.
cpio | cpio | cpio(1) | File archiver via stdin/stdout, supports cpio and tar formats.
DAR | darAUR | dar(1) | Archiver to backup large live filesystems, takes care of hard links, extended attributes, sparse files and inode types.

Tip: Both GNU and BSD tar automatically do decompression delegation for bzip2, compress, gzip, lzip, lzma and xz compressed archives. When creating archives both support the `-a` switch to automatically filter the created archive through the right compression program based on the file extension. While BSD tar recognizes compression formats based on the format, GNU tar only guesses based on the file extension.

See also #Archiving only usage.

## Compression tools

### Compression only

These compression programs implement their own file format.

Name | Package | Manual | Ext | Tar ext | Description | Parallel implementations
--- | --- | --- | --- | --- | --- | ---
bzip2 | bzip2 | bzip2(1) | .bz2, .bz | .tbz2, .tbz | Uses the Burrows–Wheeler algorithm. | lbzip2, pbzip2
gzip | gzip | gzip(1) | .gz, .z | .tgz, .taz | GNU zip, based on DEFLATE algorithm. | pigz
lrzip | lrzip | lrzip(1) | .lrz |  | Improved version of rzip, uses multiple algorithms. | is multithreaded
LZ4 | lz4 | lz4(1) | .lz4 |  | Written in C, focused on compression and decompression speed. | is multithreaded
lzip | lzip | lzip(1) | .lz |  | Uses LZMA. | plzipAUR
lzop | lzop | lzop(1) | .lzop | .tzo | Uses the LZO library (lzo). |
xz | xz | xz(1) | .xz, .lzma | .txz, .tlz | Uses LZMA, default for GNU coreutils and kernel archive files. | pixz, pxzAUR

- Parallel implementations offer improved speeds by using multiple CPU cores.
- Tar extensions refers to compressed archives where `tar` and the compression tool is used, e.g. `.tzo` is `.tar.lzo`.
- See also #Compression only usage.

### Archiving and compression

Name | Packages | Manuals | Ext | Description
--- | --- | --- | --- | ---
7z | p7zip | 7z(1) | .7z | POSIX port of 7-zip's command-line. See p7zip.
RAR | rarAUR, unrar | rar(1) | .rar | Both the format and the rar utility are proprietary.
ZIP | zip, unzip | zip(1), unzip(1) | .zip | Widely used outside of the Linux world.
Unarchiver | unarchiver | unar(1), lsar(1) | many | Command-line tool of a Mac application, supports over 40 archive formats.
ZPAQ | zpaqAUR | zpaq(1) | .zpaq | A high compression ratio archiver written in C++, uses several algorithms.

See also #Archiving and compression usage.

### Feature charts

#### Decompress

Name | gzip | bzip2 | ZIP | compress | pack | CAB | ARJ
--- | --- | --- | --- | --- | --- | --- | ---
gzip | Yes | No | Yes | Yes | Yes | No | No
p7zip | Yes | Yes | Yes | No | Yes | Yes | Yes
unarchiver | Yes | Yes | Yes | Yes | No | Yes | partial

## Usage comparison

### Archiving only usage

Name | Create archive | Extract archive | List content
--- | --- | --- | ---
tar(1) | `tar cfv archive.tar file1 file2` | `tar xfv archive.tar` | `tar -tvf archive.tar`
cpio(1) | `ls file1 file2 | cpio -o > archive.cpio` | `cpio -i -vd < archive.cpio` | `cpio -t < archive.cpio`

### Compression only usage

Name | Compress | Decompress | Decompress to stdout
--- | --- | --- | ---
bzip2(1) | `bzip2 file` | `bzip2 -d file.bz2` | `bzcat file.bz2`
gzip(1) | `gzip file` | `gzip -d file.gz` | `zcat file.gz`
lrzip(1) | `lrzip file` `lrztar folder` | `lrzip -d file.lrz` `lrztar -d folder.tar.lrz` | `lrzcat file.lrz`
xz(1) | `xz file` | `xz -d file.xz` | `xzcat file.xz`

### Archiving and compression usage

Name | Compress | Decompress | Decompress to stdout | List content
--- | --- | --- | --- | ---
7z(1) | `7z a archive.7z file1 file2` | `7z x archive.7z` | `7z e -so archive.7z file1` | `7z l archive.7z`
rar(1) & unrar | `rar a archive.rar file1 file2` | `rar x archive.rar` | `rar p -inul archive.rar file1` | `rar l archive.rar`
zip(1), unzip(1) | `zip archive.zip file1 file2` | `unzip archive.zip` | `unzip -p archive.zip file1` | `unzip -l archive.zip`

## Convenience tools

- atool — Script for managing file archives of various types.

  https://www.nongnu.org/atool/ || atool

- dtrx — An intelligent archive extraction tool.

  https://brettcsmith.org/2007/dtrx/ || dtrxAUR

- unp — Command line tool that can unpack archives easily.

  https://github.com/mitsuhiko/unp || python-unpAUR

- unpack — Wrapper script for handling multiple archive formats.

  https://github.com/githaff/unpack || unpack-gitAUR

- Bash/Functions#Extract

## Determining archive format

To extract an archive, its file format needs to be determined. If the file is properly named you can deduce its format from the file extension.

Otherwise you can use the file tool, see file(1).

## Esoteric, rare or deprecated tools

Name | Packages | Ext | Description
--- | --- | --- | ---
ARC | arcAUR | .arc, .ark | Was very popular during the early days of the dial-up BBS. Superseded by ZIP.
ARJ | arj | .arj | An archiver used on DOS/Windows in mid-1990s. This is an open source clone.
compress | ncompressAUR | .Z | The classic unix compression utility which can handle the ancient .Z archive.
LHA | lhaAUR | .lzh, .lha | Format popular in Japan, archiver to create LH-7 format archives. 32-bit only (requires multilib).
PAR2 | par2cmdline | .par2 | Parity archiver for increased data integrity. See also Parchive.
shar | sharutils | .shar | Creates self-extracting archives that are valid shell scripts.
Zoo | zooAUR | .zoo | Was mostly popular on the OpenVMS operating system before PKZIP became popular.

## Compression libraries

- Brotli — Compression algorithm for data streams using the LZ77 algorithm, Huffman coding and 2nd order context modeling.

  https://github.com/google/brotli || brotli

- zlib — Compression library implementing the deflate compression method found in gzip and PKZIP.

  https://www.zlib.net/ || zlib

- Zopfli — High compress ratio file compressor from Google, using a deflate-compatible algorithm called zopfli.

  https://github.com/google/zopfli || zopfli-gitAUR

## See also

- List of applications/Utilities#Archive managers
- List of applications/Multimedia#Image compression
- Wikipedia:Comparison of file archivers
- Wikipedia:List of archive formats
- Wikipedia:Comparison of archive formats

Categories:

- Data compression and archiving
- Commands