deb(5) — Linux manual page


deb(5)                           dpkg suite                           deb(5)

NAME         top

       deb - Debian binary package format

SYNOPSIS         top


DESCRIPTION         top

       The .deb format is the Debian binary package file format. It is
       understood since dpkg 0.93.76, and is generated by default since dpkg
       1.2.0 and 1.1.1elf (i386/ELF builds).

       The format described here is used since Debian 0.93; details of the
       old format are described in deb-old(5).

FORMAT         top

       The file is an ar archive with a magic value of !<arch>.  Only the
       common ar archive format is supported, with no long file name
       extensions, but with file names containing an optional trailing
       slash, which limits their length to 15 characters (from the 16
       allowed).  File sizes are limited to 10 ASCII decimal digits,
       allowing for up to approximately 9536.74 MiB member files.

       The tar archives currently allowed are, the old-style (v7) format,
       the pre-POSIX ustar format, a subset of the GNU format (new style
       long pathnames and long linknames, supported since dpkg;
       large file metadata since dpkg 1.18.24), and the POSIX ustar format
       (long names supported since dpkg 1.15.0).  Unrecognized tar typeflags
       are considered an error.  Each tar entry size inside a tar archive is
       limited to 11 ASCII octal digits, allowing for up to 8 GiB tar
       entries.  The GNU large file metadata support permits 95-bit tar
       entry sizes and negative timestamps, and 63-bit UID, GID and device

       The first member is named debian-binary and contains a series of
       lines, separated by newlines. Currently only one line is present, the
       format version number, 2.0 at the time this manual page was written.
       Programs which read new-format archives should be prepared for the
       minor number to be increased and new lines to be present, and should
       ignore these if this is the case.

       If the major number has changed, an incompatible change has been made
       and the program should stop. If it has not, then the program should
       be able to safely continue, unless it encounters an unexpected member
       in the archive (except at the end), as described below.

       The second required member is named control.tar.  It is a tar archive
       containing the package control information, either not compressed
       (supported since dpkg 1.17.6), or compressed with gzip (with .gz
       extension) or xz (with .xz extension, supported since 1.17.6), as a
       series of plain files, of which the file control is mandatory and
       contains the core control information, the conffiles, triggers,
       shlibs and symbols files contain optional control information, and
       the preinst, postinst, prerm and postrm files are optional maintainer
       scripts.  The control tarball may optionally contain an entry for
       ‘.’, the current directory.

       The third, last required member is named data.tar.  It contains the
       filesystem as a tar archive, either not compressed (supported since
       dpkg 1.10.24), or compressed with gzip (with .gz extension), xz (with
       .xz extension, supported since dpkg 1.15.6), bzip2 (with .bz2
       extension, supported since dpkg 1.10.24) or lzma (with .lzma
       extension, supported since dpkg 1.13.25).

       These members must occur in this exact order. Current implementations
       should ignore any additional members after data.tar.  Further members
       may be defined in the future, and (if possible) will be placed after
       these three. Any additional members that may need to be inserted
       after debian-binary and before control.tar or data.tar and which
       should be safely ignored by older programs, will have names starting
       with an underscore, ‘_’.

       Those new members which won't be able to be safely ignored will be
       inserted before data.tar with names starting with something other
       than underscores, or will (more likely) cause the major version
       number to be increased.

MEDIA TYPE         top



SEE ALSO         top

       deb-old(5), dpkg-deb(1), deb-control(5), deb-conffiles(5)
       deb-triggers(5), deb-shlibs(5), deb-symbols(5), deb-preinst(5),
       deb-postinst(5), deb-prerm(5), deb-postrm(5).

COLOPHON         top

       This page is part of the dpkg (Debian Package Manager) project.
       Information about the project can be found at 
       ⟨⟩.  If you have a bug report for
       this manual page, see
       ⟨⟩.  This page
       was obtained from the project's upstream Git repository
       ⟨⟩ on 2020-11-01.  (At
       that time, the date of the most recent commit that was found in the
       repository was 2020-07-08.)  If you discover any rendering problems
       in this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or im‐
       provements to the information in this COLOPHON (which is not part of
       the original manual page), send a mail to

1.19.6-2-g6e42d5                 2019-03-25                           deb(5)

Pages that refer to this page: dpkg(1)dpkg-deb(1)dpkg-name(1)dpkg-split(1)dselect(1)deb-control(5)deb-old(5)deb-split(5)deb-version(7)