NAME

       deb - Debian binary package format

SYNOPSIS

       filename.deb

DESCRIPTION

       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

       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 1.4.1.17; 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 numbers.

       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), xz (with .xz extension, supported since 1.17.6) or zstd (with .zst extension, supported since
       1.19.0.5ubuntu2),  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), zstd (with .zst  extension,  supported  since  1.19.0.5ubuntu2),
       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

   Current
       application/vnd.debian.binary-package

   Deprecated
       application/x-debian-package
       application/x-deb

SEE ALSO

       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).