deb(5)                    (2021-04-13)                     deb(5)

          deb - Debian binary package format


          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).

          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 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

     Page 1                       1.20.9             (printed 5/24/22)

     deb(5)                    (2021-04-13)                     deb(5)

          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 oq.cq, the current

          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, oq_cq.

          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.




          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).

     Page 2                       1.20.9             (printed 5/24/22)