Provided by: dpkg-dev_1.19.7ubuntu3_all bug


       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 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,  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, 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.





       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).