deb (file format)

File:Gdebi.png

Debian packages are standard Unix ar archives that include two tar archives. One archive holds the control information and another contains the installable data.{{cite web|url=https://raphaelhertzog.com/2010/09/17/how-to-create-debian-packages-with-alternative-compression-methods/|title=How to create Debian packages with alternative compression methods|author=Raphaël Hertzog|date=17 Sep 2010|website=raphaelhertzog.com|access-date=26 Aug 2016}}

dpkg provides the basic functionality for installing and manipulating Debian packages. Generally end users don't manage packages directly with dpkg but instead use the APT package management software or other APT front-ends such as aptitude (nCurses) and synaptic (GTK).{{cite web|url=https://wiki.debian.org/Courses/MaintainingPackages/Packages/Management|title=Debian Courses/Maintaining Packages/Packages Management|author=|date=31 Oct 2010|website=debian.org|access-date=26 Aug 2016}}

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.{{cite web|url=https://www.debian.org/doc/manuals/developers-reference/apa.en.html#alien|title=Overview of Debian Maintainer Tools / Alien|author=|date=n.d.|website=debian.org|access-date=26 Aug 2016}}

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.{{cite web|url=http://d-i.alioth.debian.org/doc/internals/ch03.html|title=Chapter 3. D-I components or udebs|author=|date=n.d.|website=debian.org|access-date=26 Aug 2016|archive-url=https://web.archive.org/web/20111203083145/http://d-i.alioth.debian.org/doc/internals/ch03.html|archive-date=3 December 2011|url-status=dead}} In particular, documentation files are normally omitted. udeb packages are not installable on a standard Debian system, but are used in Debian-Installer.

File:Deb File Structure.svgFile:Frhed hex editor displaying deb package.png displaying the raw data of a Debian package|right]]

Prior to Debian 0.93, a package consisted of a file header and two concatenated gzip archives.{{cite web|url=https://manpages.debian.org/unstable/deb-old.5|title=deb-old(5) man page: Debian old binary package format|website=manpages.debian.org|access-date=2017-04-23}} Since Debian 0.93, a deb package is implemented as an ar archive.{{cite web|url=https://www.debian.org/doc/manuals/packaging-tutorial/packaging-tutorial.en.pdf#page=7|title=Debian Packaging Tutorial|author=Lucas Nussbaum|date=16 Oct 2014|website=debian.org|access-date=26 Aug 2016}} This archive contains three files in a specific order:{{cite web|url=https://manpages.debian.org/unstable/deb.5|title=deb(5) man page: Debian binary package format|website=manpages.debian.org|access-date=2017-04-23}}{{cite web |author= |date=n.d. |title=Debian Binary Package Building HOWTO/3. Package Structure |url=https://www.tldp.org/HOWTO/Debian-Binary-Package-Building-HOWTO/x60.html |access-date=26 Aug 2016 |website=tldp.org}}

1. 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).
2. 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 and zstd is supported. The file extension changes to indicate the compression method.
3. data archive - A tar archive named data.tar contains the actual installable files. Compressing the archive with gzip, bzip2, lzma or xz and zstd is supported. The file extension changes to indicate the compression method.

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.{{cite web|url=https://manpages.debian.org/unstable/deb-control.5|title=deb-control(5) man page: Debian packages' master control file format|author=|website=manpages.debian.org|access-date=2017-04-23}}{{cite web|url=https://www.debian.org/doc/debian-policy/ch-controlfields.html#s-binarycontrolfiles|title=Debian Policy Manual Chapter 5 - Control files and their fields|author=|date=30 Mar 2016|website=debian.org|access-date=26 Aug 2016}}{{cite web|url=https://www.debian.org/doc/manuals/maint-guide/dreq.en.html#control|title=Debian New Maintainers' Guide - Ch4 Required files under the debian directory|author=Josip Rodin and Osamu Aoki|date=9 Jun 2015|website=debian.org|access-date=26 Aug 2016}}{{cite web|url=https://www.debian.org/doc/debian-policy/ch-relationships.html#s-binarydeps|title=Debian Policy Manual Ch7 - Declaring relationships between packages|author=|date=30 Mar 2016|website=debian.org|access-date=26 Aug 2016}}
• md5sums contains MD5 checksums of all files in the package in order to detect corrupt or incomplete files.{{cite web|url=https://debian-handbook.info/browse/stable/sect.package-meta-information.html|title=The Debian Administrator's Handbook - Package Meta-Information|author=|date=n.d.|website=debian-handbook.info|access-date=26 Aug 2016}}
• conffiles lists the files of the package that should be treated as configuration files. Configuration files are not overwritten during an update unless specified.{{cite web|url=https://www.debian.org/doc/manuals/debian-faq/pkg-basics.en.html|title=Chapter 7. Basics of the Debian package management system|author=|date=12 August 2019|website=debian.org|access-date=27 May 2021}}
• preinst, postinst, prerm and postrm are optional scripts that are executed before or after installing or removing the package.{{cite web|url=https://wiki.debian.org/MaintainerScripts|title=Debian Maintainer Scripts|author=|date=11 Oct 2012|website=debian.org|access-date=26 Aug 2016}}
• config is an optional script that supports the debconf configuration mechanism.{{cite web |author=Joey Hess |date=n.d. |title=The Debconf Programmer's Tutorial - The Config Script |url=https://www.fifi.org/doc/debconf-doc/tutorial.html#AEN113 |access-date=26 Aug 2016 |website=fifi.org}}
• shlibs list of shared library dependencies.{{cite web|url=https://manpages.debian.org/unstable/dpkg-shlibdeps.1|title=dpkg-shlibdeps(1) man page|author=|website=manpages.debian.org|access-date=2017-04-23}}{{cite web|url=https://www.debian.org/doc/debian-policy/ch-sharedlibs.html#s-sharedlibs-depends|title=Debian Policy - 8.6 Dependencies between the library and other packages|author=|date=30 Mar 2016|website=debian.org|access-date=26 Aug 2016}}

Debian-based distributions support OpenPGP signature verification of signed Debian packages, but most (if not all) have this feature disabled by default.{{cite web |author=Joe Damato |date=28 Oct 2014 |title=HOWTO: GPG sign and verify deb packages and APT repositories |url=https://blog.packagecloud.io/eng/2014/10/28/howto-gpg-sign-verify-deb-packages-apt-repositories/ |access-date=26 Aug 2016 |website=packagecloud.io}} 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.{{cite web |author= |date=4 Aug 2015 |title=APT repository internals |url=https://blog.packagecloud.io/eng/2015/08/04/apt-repository-internals/ |access-date=26 Aug 2016 |website=packagecloud.io}}{{cite web|url=https://wiki.debian.org/SecureApt|title=SecureApt - All about secure apt|author=|date=22 Sep 2015|website=debian.org|access-date=26 Aug 2016}} Currently there are two different implementations for signing individual packages. The first is done via the debsigs / debsig-verify toolset, which is supported by dpkg.{{cite web|url=https://manpages.debian.org/unstable/debsig-verify.1|title=debsig-verify(1) man page|author=|website=manpages.debian.org|access-date=2017-04-23}} The second is done through the dpkg-sig program which is not supported by dpkg, so the packages have to be manually checked with the dpkg-sig program.{{cite web|url=https://manpages.debian.org/unstable/debsigs.1|title=debsigs(1) man page|author=|website=manpages.debian.org|access-date=2017-04-23}}{{cite web|url=http://dpkg-sig.turmzimmer.net/ |title=Integrating signatures into Debian archive files |author=Andreas Barth |date=29 Dec 2003 |website=turmzimmer.net |access-date=29 Dec 2003 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20060222013602/http://dpkg-sig.turmzimmer.net/ |archive-date=2006-02-22}}{{cite web|url=http://dpkg-sig.turmzimmer.net/policy.html |title=policy for debsigs |date=1 Feb 2004 |website=turmzimmer.net |access-date=1 Feb 2004 |url-status=bot: unknown |archive-url=https://web.archive.org/web/20060714233154/http://dpkg-sig.turmzimmer.net/policy.html |archive-date=2006-07-14}} 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 about the binary package format.{{cite web|url=https://www.debian.org/doc/manuals/debian-handbook/packaging-system.en.html|title=The Debian Administrator's Handbook - Ch5. Packaging System: Tools and Fundamental Principles|author=|date=n.d.|website=debian.org|access-date=26 Aug 2016}}

• Debian packages are used in distributions based on Debian, such as, Linux Mint (LMDE),{{Cite web |last=Kumar |first=Sarvottam |date=2020-07-03 |title=Linux Mint 20 "Ulyana" Review: The Most Complete OS For Everyone |url=https://fossbytes.com/linux-mint-20-ulyana-review/ |url-status=live |archive-url=https://archive.today/20240515203221/https://fossbytes.com/linux-mint-20-ulyana-review/ |archive-date=2024-05-15 |access-date=2024-05-15 |website=Fossbytes |language=en-US}}{{Cite web |last=Saive |first=Ravi |date=2022-12-12 |title=3 Ways to Install Deb Packages in Ubuntu, Mint & Debian |url=https://www.ubuntumint.com/install-deb-files-ubuntu-mint-debian/ |url-status=live |archive-url=https://archive.today/20240515203108/https://www.ubuntumint.com/install-deb-files-ubuntu-mint-debian/ |archive-date=2024-05-15 |access-date=2024-05-15 |website=www.ubuntumint.com |language=en-US}} KDE neon, Ubuntu and many others.
• Fink, a port of dpkg and APT to macOS, uses deb packages.{{cite web |author= |date=6 Jun 2015 |title=Fink FAQ - General Questions |url=https://www.finkproject.org/faq/general.php |access-date=26 Aug 2016 |website=finkproject.org}}{{cite web |author= |date=6 Jun 2015 |title=Fink FAQ - Installing, Using and Maintaining Fink |url=https://www.finkproject.org/faq/usage-fink.php |access-date=26 Aug 2016 |website=finkproject.org}}
• Nexenta OS, a discontinued OS based on OpenSolaris, 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.
• Some jailbroken iOS devices (iPhones, iPads and iPods).{{cite web |author=Jay Freeman |date=n.d. |title=Bringing Debian APT to the iPhone |url=https://www.saurik.com/id/1 |access-date=26 Aug 2016 |website=saurik.com}}{{cite web|url=https://www.engadget.com/2008/02/28/debian-style-installation-arrives-on-iphone/|title=Debian-style installation arrives on iPhone|author=Erica Sadun|date=28 Feb 2008|website=engadget.com|access-date=26 Aug 2016}}
• Ipkg and Opkg, which both use .ipk packages that resemble Debian's dpkg

• Termux, which is a GNU environment for Android.

• List of archive formats
• dpkg
• wpkg
• CheckInstall
• List of software package management systems

{{Reflist|2}}

• [https://www.debian.org/doc/manuals/debian-faq/pkg-basics.en.html Debian FAQ: Basics of the Debian package management system]
• [https://antumdeluge.github.io/debreate-web/ Debreate - A powerful Debian Package Builder]
• [https://wiki.debian.org/Teams/Dpkg/DebSupport .deb feature support]
• [https://web.archive.org/web/20160307164024/https://lists.debian.org/debian-user/2001/07/msg00645.html Manipulating debs directly with standard utilities]
• [https://www.youtube.com/watch?v=lFzPrzY2KFM&v3 Anatomy of a Debian package video]

{{Debian}}

{{Archive formats}}

{{Package management systems}}

Category:Archive formats

Category:Debian

Category:Dpkg

Category:Filename extensions

Category:Ubuntu