Provided by: dpkg_1.17.5ubuntu5.8_amd64 bug


       dpkg - package manager for Debian


       dpkg [option...] action


       This  manual  is  intended for users wishing to understand dpkg's command line options and
       package states in more detail than that provided by dpkg --help.

       It should not be used by package maintainers wishing to understand how dpkg  will  install
       their  packages.  The descriptions of what dpkg does when installing and removing packages
       are particularly inadequate.


       dpkg is a tool to install, build, remove and manage Debian packages. The primary and  more
       user-friendly  front-end  for  dpkg is aptitude(1). dpkg itself is controlled entirely via
       command line parameters, which consist of exactly one action and zero or more options. The
       action-parameter  tells  dpkg what to do and options control the behavior of the action in
       some way.

       dpkg can also be used as a  front-end  to  dpkg-deb(1)  and  dpkg-query(1).  The  list  of
       supported  actions  can  be  found  later on in the ACTIONS section. If any such action is
       encountered dpkg just runs dpkg-deb or dpkg-query with the parameters given to it, but  no
       specific  options  are currently passed to them, to use any such option the back-ends need
       to be called directly.


       dpkg maintains some usable  information  about  available  packages.  The  information  is
       divided in three classes: states, selection states and flags. These values are intended to
       be changed mainly with dselect.

   Package states
              The package is not installed on your system.

              Only the configuration files of the package exist on the system.

              The installation of the package has  been  started,  but  not  completed  for  some

              The package is unpacked, but not configured.

              The  package  is unpacked and configuration has been started, but not yet completed
              for some reason.

              The package awaits trigger processing by another package.

              The package has been triggered.

              The package is unpacked and configured OK.

   Package selection states
              The package is selected for installation.

       hold   A package marked to be on hold is not handled by dpkg, unless  forced  to  do  that
              with option --force-hold.

              The  package  is  selected  for  deinstallation  (i.e. we want to remove all files,
              except configuration files).

       purge  The package is selected to be purged (i.e. we want to remove everything from system
              directories, even configuration files).

   Package flags
              A  package  marked  reinst-required  is  broken  and requires reinstallation. These
              packages cannot be removed, unless forced with option --force-remove-reinstreq.


       -i, --install package-file...
              Install the package. If --recursive or -R option is  specified,  package-file  must
              refer to a directory instead.

              Installation consists of the following steps:

              1. Extract the control files of the new package.

              2.   If  another  version  of  the  same  package  was  installed  before  the  new
              installation, execute prerm script of the old package.

              3. Run preinst script, if provided by the package.

              4. Unpack the new files, and at the same time back up the old  files,  so  that  if
              something goes wrong, they can be restored.

              5.   If  another  version  of  the  same  package  was  installed  before  the  new
              installation, execute the postrm script of the old package. Note that  this  script
              is  executed  after  the  preinst  script of the new package, because new files are
              written at the same time old files are removed.

              6. Configure the package. See --configure for detailed information about  how  this
              is done.

       --unpack package-file...
              Unpack  the  package,  but  don't  configure  it.  If  --recursive  or -R option is
              specified, package-file must refer to a directory instead.

       --configure package...|-a|--pending
              Configure a package which has been unpacked but  not  yet  configured.   If  -a  or
              --pending  is  given instead of package, all unpacked but unconfigured packages are

              To  reconfigure  a  package  which   has   already   been   configured,   try   the
              dpkg-reconfigure(8) command instead.

              Configuring consists of the following steps:

              1.  Unpack  the  conffiles, and at the same time back up the old conffiles, so that
              they can be restored if something goes wrong.

              2. Run postinst script, if provided by the package.

       --triggers-only package...|-a|--pending
              Processes only triggers. All pending triggers will be processed. If  package  names
              are  supplied  only  those  packages' triggers will be processed, exactly once each
              where  necessary.  Use  of  this  option  may  leave  packages  in   the   improper
              triggers-awaited  and  triggers-pending states. This can be fixed later by running:
              dpkg --configure --pending.

       -r, --remove, -P, --purge package...|-a|--pending
              Remove an installed package. -r or --remove  remove  everything  except  conffiles.
              This  may  avoid  having  to  reconfigure  the  package if it is reinstalled later.
              (Conffiles are configuration files that are listed in the DEBIAN/conffiles  control
              file). -P or --purge removes everything, including conffiles. If -a or --pending is
              given instead of a package name, then all  packages  unpacked,  but  marked  to  be
              removed   or   purged   in   file  /var/lib/dpkg/status,  are  removed  or  purged,
              respectively. Note: some configuration files might be unknown to dpkg because  they
              are created and handled separately through the configuration scripts. In that case,
              dpkg won't remove them by itself, but the package's postrm script (which is  called
              by  dpkg),  has  to  take  care of their removal during purge. Of course, this only
              applies to  files  in  system  directories,  not  configuration  files  written  to
              individual users' home directories.

              Removing of a package consists of the following steps:

              1. Run prerm script

              2. Remove the installed files

              3. Run postrm script

       -V, --verify [package-name...]
              Verifies  the  integrity  of  package-name or all packages if omitted, by comparing
              information from the installed paths with the database metadata.

              The output format is selectable with the --verify-format option, which  by  default
              uses  the  rpm  format,  but  that might change in the future, and as such programs
              parsing this command output should be explicit about the format they expect.

       --update-avail, --merge-avail Packages-file
              Update dpkg's and dselect's idea of  which  packages  are  available.  With  action
              --merge-avail,  old  information  is  combined with information from Packages-file.
              With action --update-avail, old information is replaced with the information in the
              Packages-file.  The Packages-file distributed with Debian is simply named Packages.
              dpkg keeps its record of available packages in /var/lib/dpkg/available.

              A simpler one-shot command to retrieve and update the  available  file  is  dselect
              update.  Note that this file is mostly useless if you don't use dselect but an APT-
              based frontend: APT has its own system to keep track of available packages.

       -A, --record-avail package-file...
              Update dpkg and dselect's idea of which packages  are  available  with  information
              from  the  package package-file. If --recursive or -R option is specified, package-
              file must refer to a directory instead.

              Now obsolete and a no-op as dpkg will automatically forget uninstalled  unavailable

              Erase the existing information about what packages are available.

        -C, --audit
              Searches  for packages that have been installed only partially on your system. dpkg
              will suggest what to do with them to get them working.

       --get-selections [package-name-pattern...]
              Get list of package selections, and write it to stdout.  Without  a  pattern,  non-
              installed  packages  (i.e.  those  which  have  been previously purged) will not be

              Set package selections using file read from stdin.  This  file  should  be  in  the
              format  'package  state',  where state is one of install, hold, deinstall or purge.
              Blank lines and comment lines beginning with '#' are also permitted.

              The available file needs to be up-to-date for this command to be useful,  otherwise
              unknown  packages  will  be  ignored  with  a  warning.  See the --update-avail and
              --merge-avail commands for more information.

              Set the requested state of every  non-essential  package  to  deinstall.   This  is
              intended  to be used immediately before --set-selections, to deinstall any packages
              not in list given to --set-selections.

              Searches for packages selected for installation, but which for  some  reason  still
              haven't been installed.

       --add-architecture architecture
              Add  architecture  to the list of architectures for which packages can be installed
              without using --force-architecture. The architecture dpkg is built  for  (i.e.  the
              output of --print-architecture) is always part of that list.

       --remove-architecture architecture
              Remove  architecture  from  the  list  of  architectures  for which packages can be
              installed without using --force-architecture. If the architecture is  currently  in
              use   in   the   database   then   the   operation   will  be  refused,  except  if
              --force-architecture is specified. The architecture dpkg is  built  for  (i.e.  the
              output of --print-architecture) can never be removed from that list.

              Print architecture of packages dpkg installs (for example, "i386").

              Print  a  newline-separated  list  of the extra architectures dpkg is configured to
              allow packages to be installed for.

       --compare-versions ver1 op ver2
              Compare version numbers, where op is a binary operator. dpkg returns success  (zero
              result)  if  the  specified  condition  is  satisfied, and failure (nonzero result)
              otherwise. There are two groups of operators, which differ in  how  they  treat  an
              empty ver1 or ver2. These treat an empty version as earlier than any version: lt le
              eq ne ge gt. These treat an empty version as later than any  version:  lt-nl  le-nl
              ge-nl  gt-nl. These are provided only for compatibility with control file syntax: <
              << <= = >= >> >.

       -?, --help
              Display a brief help message.

              Give help about the --force-thing options.

       -Dh, --debug=help
              Give help about debugging options.

              Display dpkg version information.

       dpkg-deb actions
              See dpkg-deb(1) for more information about the following actions.

              -b, --build directory [archive|directory]
                  Build a deb package.
              -c, --contents archive
                  List contents of a deb package.
              -e, --control filename [directory]
                  Extract control-information from a package.
              -x, --extract archive directory
                  Extract the files contained by package.
              -X, --vextract archive directory
                  Extract and display the filenames contained by a
              -f, --field  archive [control-field...]
                  Display control field(s) of a package.
              --fsys-tarfile archive
                  Display the filesystem tar-file contained by a
                  Debian package.
              -I, --info archive [control-file...]
                  Show information about a package.

       dpkg-query actions
              See dpkg-query(1) for more information about the following actions.

              -l, --list package-name-pattern...
                  List packages matching given pattern.
              -s, --status package-name...
                  Report status of specified package.
              -L, --listfiles package-name...
                  List files installed to your system from package-name.
              -S, --search filename-search-pattern...
                  Search for a filename from installed packages.
              -p, --print-avail package-name...
                  Display details about package-name, as found in
                  /var/lib/dpkg/available. Users of APT-based frontends
                  should use apt-cache show package-name instead.


       All options can be specified both on the command line and in the dpkg  configuration  file
       /etc/dpkg/dpkg.cfg  or  fragment  files (with names matching this shell pattern '[0-9a-zA-
       Z_-]*')  on  the  configuration  directory  /etc/dpkg/dpkg.cfg.d/.  Each   line   in   the
       configuration  file  is  either an option (exactly the same as the command line option but
       without leading hyphens) or a comment (if it starts with a #).

              Change after how many errors dpkg will abort. The default is 50.

       -B, --auto-deconfigure
              When a package is removed, there is a possibility that  another  installed  package
              depended  on  the  removed  package.  Specifying  this  option will cause automatic
              deconfiguration of the package which depended on the removed package.

       -Doctal, --debug=octal
              Switch debugging on. octal is formed by bitwise-orring desired values together from
              the  list  below  (note  that  these  values may change in future releases). -Dh or
              --debug=help display these debugging values.

                  Number   Description
                       1   Generally helpful progress information
                       2   Invocation and status of maintainer scripts
                      10   Output for each file processed
                     100   Lots of output for each file processed
                      20   Output for each configuration file
                     200   Lots of output for each configuration file
                      40   Dependencies and conflicts
                     400   Lots of dependencies/conflicts output
                   10000   Trigger activation and processing
                   20000   Lots of output regarding triggers
                   40000   Silly amounts of output regarding triggers
                    1000   Lots of drivel about e.g. the dpkg/info dir
                    2000   Insane amounts of drivel

       --force-things, --no-force-things, --refuse-things

              Force or refuse (no-force and refuse mean the same thing) to do some things. things
              is  a  comma  separated  list  of  things  specified below. --force-help displays a
              message describing them.  Things marked with (*) are forced by default.

              Warning: These options are mostly intended to be used by experts only.  Using  them
              without fully understanding their effects may break your whole system.

              all: Turns on (or off) all force options.

              downgrade(*): Install a package, even if newer version of it is already installed.

              Warning:  At  present  dpkg  does  not do any dependency checking on downgrades and
              therefore will not warn you if the downgrade breaks the dependency  of  some  other
              package.   This  can  have  serious  side  effects,  downgrading  essential  system
              components can even make your whole system unusable. Use with care.

              configure-any: Configure also any unpacked but unconfigured packages on  which  the
              current package depends.

              hold: Process packages even when marked "hold".

              remove-reinstreq:  Remove  a  package,  even  if  it's broken and marked to require
              reinstallation. This may, for example, cause parts of the package to remain on  the
              system, which will then be forgotten by dpkg.

              remove-essential:  Remove,  even  if the package is considered essential. Essential
              packages contain mostly very basic Unix commands. Removing  them  might  cause  the
              whole system to stop working, so use with caution.

              depends: Turn all dependency problems into warnings.

              depends-version: Don't care about versions when checking dependencies.

              breaks: Install, even if this would break another package.

              conflicts:  Install,  even if it conflicts with another package. This is dangerous,
              for it will usually cause overwriting of some files.

              confmiss: If a conffile is missing and the  version  in  the  package  did  change,
              always  install the missing conffile without prompting. This is dangerous, since it
              means not preserving a change (removing) made to the file.

              confnew: If a conffile has been modified and the version in the package did change,
              always  install  the  new  version without prompting, unless the --force-confdef is
              also specified, in which case the default action is preferred.

              confold: If a conffile has been modified and the version in the package did change,
              always  keep  the old version without prompting, unless the --force-confdef is also
              specified, in which case the default action is preferred.

              confdef: If a conffile has been modified and the version in the package did change,
              always  choose  the default action without prompting. If there is no default action
              it will stop to ask the user unless --force-confnew or --force-confold is also been
              given, in which case it will use that to decide the final action.

              confask:  If  a  conffile  has  been  modified  always offer to replace it with the
              version in the package, even if the version in the package did not change.  If  any
              of  --force-confmiss,  --force-confnew, --force-confold, or --force-confdef is also
              given, it will be used to decide the final action.

              overwrite: Overwrite one package's file with another's file.

              overwrite-dir Overwrite one package's directory with another's file.

              overwrite-diverted: Overwrite a diverted file with an undiverted version.

              unsafe-io: Do not perform  safe  I/O  operations  when  unpacking.  Currently  this
              implies  not  performing  file  system syncs before file renames, which is known to
              cause substantial performance degradation on some file systems,  unfortunately  the
              ones that require the safe I/O on the first place due to their unreliable behaviour
              causing zero-length files on abrupt system crashes.

              Note: For ext4,  the  main  offender,  consider  using  instead  the  mount  option
              nodelalloc,  which  will  fix  both the performance degradation and the data safety
              issues, the latter by making the file  system  not  produce  zero-length  files  on
              abrupt system crashes with any software not doing syncs before atomic renames.

              Warning:  Using  this  option might improve performance at the cost of losing data,
              use with care.

              architecture: Process even packages with wrong or no architecture.

              bad-version: Process even packages with wrong versions.

              bad-path: PATH is missing important programs, so problems are likely.

              not-root: Try to (de)install things even when not root.

              bad-verify: Install a package even if it fails authenticity check.

              Ignore dependency-checking for specified packages (actually, checking is performed,
              but only warnings about conflicts are given, nothing else).

       --no-act, --dry-run, --simulate
              Do  everything  which  is supposed to be done, but don't write any changes. This is
              used to see what would happen with the specified action, without actually modifying

              Be  sure  to  give  --no-act  before the action-parameter, or you might end up with
              undesirable results. (e.g. dpkg --purge foo --no-act will first purge  package  foo
              and  then  try  to  purge package --no-act, even though you probably expected it to
              actually do nothing)

       -R, --recursive
              Recursively handle all regular files matching  pattern  *.deb  found  at  specified
              directories and all of its subdirectories. This can be used with -i, -A, --install,
              --unpack and --avail actions.

       -G     Don't install a package  if  a  newer  version  of  the  same  package  is  already
              installed. This is an alias of --refuse-downgrade.

              Change  default  administrative  directory,  which  contains  many  files that give
              information about status of installed or uninstalled packages, etc.   (Defaults  to

              Change  default installation directory which refers to the directory where packages
              are to be installed. instdir is also  the  directory  passed  to  chroot(2)  before
              running package's installation scripts, which means that the scripts see instdir as
              a root directory.  (Defaults to /)

              Changing root changes instdir to dir and admindir to dir/var/lib/dpkg.

       -O, --selected-only
              Only process the packages that are selected for installation. The actual marking is
              done with dselect or by dpkg, when it handles packages. For example, when a package
              is removed, it will be marked selected for deinstallation.

       -E, --skip-same-version
              Don't install the package if the same version of the package is already installed.

              Set an invoke hook command to be run via “sh -c” before or after the dpkg  run  for
              the  unpack, configure, install, triggers-only, remove and purge dpkg actions. This
              option can be specified multiple times. The order  the  options  are  specified  is
              preserved,  with  the  ones  from  the  configuration files taking precedence.  The
              environment variable DPKG_HOOK_ACTION is set for the  hooks  to  the  current  dpkg
              action.  Note: front-ends might call dpkg several times per invocation, which might
              run the hooks more times than expected.

              Set glob-pattern as a path filter, either by excluding or  re-including  previously
              excluded paths matching the specified patterns during install.

              Warning:  take  into  account  that  depending  on  the  excluded  paths  you might
              completely break your system, use with caution.

              The glob patterns use the same wildcards used in the shell, were  '*'  matches  any
              sequence  of  characters,  including  the  empty  string and also '/'. For example,
              '/usr/*/READ*' matches '/usr/share/doc/package/README'.  As usual, '?' matches  any
              single  character  (again,  including '/'). And '[' starts a character class, which
              can contain a list of characters, ranges  and  complementations.  See  glob(7)  for
              detailed  information  about  globbing.  Note: the current implementation might re-
              include more directories and symlinks than needed, to be on the safe side and avoid
              possible unpack failures, future work might fix this.

              This  can  be  used to remove all paths except some particular ones; a typical case


              to remove all documentation files except the copyright files.

              These two options can be specified multiple times, and interleaved with each other.
              Both  are processed in the given order, with the last rule that matches a file name
              making the decision.

       --verify-format format-name
              Sets the output format for the --verify command.

              The only currently supported output format is rpm, which consists  of  a  line  for
              every  path  that failed any check. The lines start with 9 characters to report the
              specific check results, a '?' implies the check could not be done (lack of support,
              file  permissions,  etc),  '.'   implies  the  check  passed,  and  an alphanumeric
              character implies a specific check failed; the only functional check is  an  md5sum
              verification  denoted  with a '5' on the third character. The line is followed by a
              space and an attribute character (currently 'c' for conffiles), another  space  and
              the pathname.

       --status-fd n
              Send machine-readable package status and progress information to file descriptor n.
              This option can be specified multiple  times.  The  information  is  generally  one
              record per line, in one of the following forms:

              status: package: status
                     Package status changed; status is as in the status file.

              status: package : error : extended-error-message
                     An  error  occurred. Any possible newlines in extended-error-message will be
                     converted to spaces before output.

              status: file : conffile-prompt : 'real-old' 'real-new' useredited distedited
                     User is being asked a conffile question.

              processing: stage: package
                     Sent just before a processing stage starts. stage is one of upgrade, install
                     (both sent before unpacking), configure, trigproc, disappear, remove, purge.

              Send  machine-readable  package  status  and  progress  information  to  the  shell
              command's standard input. This option can be specified multiple times.  The  output
              format used is the same as in --status-fd.

              Log  status  change  updates  and  actions  to  filename,  instead  of  the default
              /var/log/dpkg.log. If this option is given multiple times,  the  last  filename  is
              used. Log messages are of the form `YYYY-MM-DD HH:MM:SS status state pkg installed-
              version' for status change updates;  `YYYY-MM-DD  HH:MM:SS  action  pkg  installed-
              version  available-version'  for  actions  where action is one of install, upgrade,
              remove, purge; and `YYYY-MM-DD HH:MM:SS conffile filename  decision'  for  conffile
              changes where decision is either install or keep.

              Do not try to verify package signatures.

              Do  not run any triggers in this run (activations will still be recorded).  If used
              with --configure package or --triggers-only package then the named package postinst
              will  still  be  run  even if only a triggers run is needed. Use of this option may
              leave packages in the improper triggers-awaited and triggers-pending  states.  This
              can be fixed later by running: dpkg --configure --pending.

              Cancels a previous --no-triggers.


       HOME   If  set,  dpkg  will  use  it as the directory from which to read the user specific
              configuration file.

       TMPDIR If set, dpkg will use it as the directory in which to create  temporary  files  and

       PAGER  The program dpkg will execute when displaying the conffiles.

       SHELL  The program dpkg will execute when starting a new shell.

              Sets  the  number  of  columns  dpkg  should  use  when  displaying formatted text.
              Currently only used by -l.

              Defined by dpkg on the  shell  spawned  on  the  conffile  prompt  to  examine  the
              situation. Current valid value: conffile-prompt.

              Defined  by  dpkg  on  the  shell  spawned  on  the  conffile prompt to examine the
              situation. Contains the path to the old conffile.

              Defined by dpkg on the  shell  spawned  on  the  conffile  prompt  to  examine  the
              situation. Contains the path to the new conffile.

              Defined  by  dpkg  on  the  maintainer  script  environment  to  the version of the
              currently running dpkg instance.

              Defined by dpkg on the maintainer script environment  to  the  (non-arch-qualified)
              package name being handled.

              Defined  by  dpkg  on  the  maintainer  script environment to the package reference
              count,  i.e.  the  number  of  package  instances  with  a   state   greater   than
              not-installed. Since dpkg 1.17.2.

              Defined  by  dpkg  on  the  maintainer  script  environment to the architecture the
              package got built for.

              Defined by dpkg on the maintainer script environment to  the  name  of  the  script
              running (preinst, postinst, prerm, postrm).


              Configuration fragment files.

              Configuration file with default options.

              Default log file (see /etc/dpkg/dpkg.cfg(5) and option --log).

       The  other  files  listed below are in their default directories, see option --admindir to
       see how to change locations of these files.

              List of available packages.

              Statuses of available packages. This file  contains  information  about  whether  a
              package  is  marked  for  removing or not, whether it is installed or not, etc. See
              section INFORMATION ABOUT PACKAGES for more info.

              The status file is backed up daily in /var/backups. It can be useful if  it's  lost
              or corrupted due to filesystems troubles.

       The  following  files  are components of a binary package. See deb(5) for more information
       about them:


       --no-act usually gives less information than might be helpful.


       To list installed packages related to the editor vi(1) (note that dpkg-query does not load
       the  available  file  anymore by default, and the dpkg-query --load-avail option should be
       used instead for that):
            dpkg -l '*vi*'

       To see the entries in /var/lib/dpkg/available of two packages:
            dpkg --print-avail elvis vim | less

       To search the listing of packages yourself:
            less /var/lib/dpkg/available

       To remove an installed elvis package:
            dpkg -r elvis

       To install a package, you first need to find it in an archive or CDROM. The available file
       shows that the vim package is in section "editors":
            cd /media/cdrom/pool/main/v/vim
            dpkg -i vim_4.5-3.deb

       To make a local copy of the package selection states:
            dpkg --get-selections >myselections

       You  might  transfer this file to another computer, and after having updated the available
       file    there    with    your    package    manager    frontend     of     choice     (see for more details), for example:
            apt-cache dumpavail >"$avail"
            dpkg --merge-avail "$avail"
            rm "$avail"
       you can install it with:
            dpkg --clear-selections
            dpkg --set-selections <myselections

       Note  that  this  will not actually install or remove anything, but just set the selection
       state on the requested packages. You will need some other application to actually download
       and install the requested packages. For example, run apt-get dselect-upgrade.

       Ordinarily,  you  will  find  that dselect(1) provides a more convenient way to modify the
       package selection states.


       Additional functionality can be gained by installing any of the following  packages:  apt,
       aptitude and debsums.


       aptitude(1), apt(1), dselect(1), dpkg-deb(1), dpkg-query(1), deb(5), deb-control(5),
       dpkg.cfg(5), and dpkg-reconfigure(8).


       See /usr/share/doc/dpkg/THANKS for the list of people who have contributed to dpkg.