deb is the format, as well as extension 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 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, and ...

ar archives that include two tar 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 ...

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

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

Implementation

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

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 configuration mechanism. * shlibs list of shared library dependencies.

Signed packages

Debian-based distributions support OpenPGP 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 the ...

and many others. * Fink, a port of

and APT to

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 th ...

, 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 De ...

. * Some jailbroken iOS devices (iPhones, iPads and iPods). *

Ipkg ipkg, or the Itsy Package Management System, is a discontinued lightweight package management system designed for embedded devices that resembles Debian's dpkg. It was used in the Unslung operating system for the Linksys NSLU2 (Optware), in O ...

and

Opkg opkg (''open package management'') is a lightweight package management system based upon ipkg. It is written in C and resembles Advanced Package Tool (APT)/ dpkg in operation. It is intended for use on embedded Linux devices and is used in thi ...

, which both use .ipk packages that resemble

* Termux, which is a GNU environment for

Android Android may refer to: Science and technology * Android (robot), a humanoid robot or synthetic organism designed to imitate a human * Android (operating system), Google's mobile operating system ** Bugdroid, a Google mascot sometimes referred to ...

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