deb is the format, as well as

extension Extension, extend or extended may refer to: Mathematics Logic or set theory * Axiom of extensionality * Extensible cardinal * Extension (model theory) * Extension (predicate logic), the set of tuples of values that satisfy the predicate * Ext ...

of the software package format for the

Debian Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of De ...

Linux distribution A Linux distribution (often abbreviated as distro) is an operating system made from a software collection that includes the Linux kernel and, often, a package management system. Linux users usually obtain their operating system by downloading on ...

and its derivatives.

Design

Debian packages are standard

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, a ...

ar archives that include two

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

archives. One archive holds the control information and another contains the installable data.

dpkg dpkg is the software at the base of the package management system in the free operating system Debian and its numerous derivatives. dpkg is used to install, remove, and provide information about .deb packages. dpkg (Debian Package) itself is a ...

provides the basic functionality for installing and manipulating Debian packages. Generally end users don't manage packages directly with

but instead use the

APT Apt. is an abbreviation for apartment. Apt may also refer to: Places * Apt Cathedral, a former cathedral, and national monument of France, in the town of Apt in Provence * Apt, Vaucluse, a commune of the Vaucluse département of France * A ...

package management software or other APT front-ends such as

aptitude An aptitude is a component of a competence to do a certain kind of work at a certain level. Outstanding aptitude can be considered "talent". Aptitude is inborn potential to perform certain kinds of activities, whether physical or mental, and ...

(

nCurses ncurses (new curses) is a programming library providing an application programming interface (API) that allows the programmer to write text-based user interfaces (TUI) in a terminal-independent manner. It is a toolkit for developing " GUI-li ...

) and synaptic ( GTK). Debian packages can be converted into other package formats and vice versa using alien, and created from source code using

checkinstall CheckInstall is a computer program for Unix-like operating systems which eases the installation and uninstallation of software compiled from source by making use of package management systems. After software compilation it can automatically g ...

or the Debian Package Maker. Some core Debian packages are available as udebs ("micro debs"), and are typically used only for bootstrapping a Debian installation. Although these files use the ''udeb'' filename extension, they adhere to the same structure specification as ordinary ''deb'' files. However, unlike their ''deb'' counterparts, ''udeb'' packages contain only essential functional files. In particular, documentation files are normally omitted. ''udeb'' packages are not installable on a standard Debian system, but are used in

Debian-Installer Debian-Installer is a system installer designed for the Debian Linux distribution. It originally appeared in the Debian release 3.1 (Sarge), released on June 6, 2005, although the first release of a Linux distribution that used it was Skolelinu ...

Implementation

Prior to Debian 0.93, a package consisted of a file header and two concatenated

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 ...

archives. Since Debian 0.93, a deb package is implemented as an ar archive. This archive contains three files in a specific order: # debian-binary - A text file named debian-binary containing a single line giving the package format version number. (2.0 for current versions of Debian). # control archive - A tar archive named control.tar contains the maintainer scripts and the package meta-information (package name, version, dependencies and maintainer). Compressing the archive with

or xz is supported. The file extension changes to indicate the compression method. # data archive - A tar archive named data.tar contains the actual installable files. Compressing the archive with

, bzip2, lzma or xz is supported. The file extension changes to indicate the compression method.

Control archive

The control archive contents can include the following files: * control contains a brief description of the package as well as other information such as its dependencies. * md5sums contains MD5

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 dat ...

s of all files in the package in order to detect corrupt or incomplete files. * conffiles lists the files of the package that should be treated as configuration files. Configuration files are not overwritten during an update unless specified. * preinst, postinst, prerm and postrm are optional scripts that are executed before or after installing or removing the package. * config is an optional script that supports the

debconf is a software utility for performing system-wide configuration tasks on Unix-like operating systems. It is developed for the Debian Linux distribution, and is closely integrated with Debian's package management system, dpkg. When packages ar ...

configuration mechanism. * shlibs list of shared library dependencies.

Signed packages

Debian-based distributions support

OpenPGP Pretty Good Privacy (PGP) is an encryption program that provides cryptographic privacy and authentication for data communication. PGP is used for signing, encrypting, and decrypting texts, e-mails, files, directories, and whole disk partiti ...

signature verification of signed Debian packages, but most (if not all) have this feature disabled by default. Instead packages are verified by signing the repository metadata (i.e. Release files). The metadata files in turn include checksums for the repository files as a means to verify authenticity of the files. Currently there are two different implementations for signing individual packages. The first is done via the debsigs / debsig-verify toolset, which is supported by

. The second is done through the dpkg-sig program which is not supported by

, so the packages have to be manually checked with the dpkg-sig program. Both formats add new sections to the ar archive to store the signature information, but the formats are not compatible with one another. Neither of the modifications to the package format are listed in the official Debian handbook or

man page A man page (short for manual page) is a form of software documentation usually found on a Unix or Unix-like operating system. Topics covered include computer programs (including library and system calls), formal standards and conventions, and ev ...

about the binary package format.

Adoption

* Debian packages are used in distributions based on Debian, such as

Ubuntu Ubuntu ( ) is a Linux distribution based on Debian and composed mostly of free and open-source software. Ubuntu is officially released in three editions: '' Desktop'', '' Server'', and ''Core'' for Internet of things devices and robots. All th ...

and many others. * Fink, a port of

and

macOS macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac (computer), Mac computers. Within the market of ...

, uses deb packages. * Nexenta OS, a discontinued OS based on

OpenSolaris OpenSolaris () is a discontinued open-source computer operating system based on Solaris and created by Sun Microsystems. It was also, perhaps confusingly, the name of a project initiated by Sun to build a developer and user community around t ...

, included Debian package management software and the use of deb packages. * Debian GNU/kFreeBSD, an OS that uses a GNU based userland and the FreeBSD kernel. *

Debian GNU/Hurd Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of Deb ...

. * Some jailbroken iOS devices (iPhones, iPads and iPods). * Ipkg and Opkg, which both use .ipk packages that resemble

* Termux, which is a

GNU GNU () is an extensive collection of 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 ...

environment for Android.

References

External links

Debian FAQ: Basics of the Debian package management system

Debreate - A powerful Debian Package Builder

.deb feature support

Anatomy of a Debian package video
{{Package management systems Archive formats Debian Dpkg Filename extensions Ubuntu