Provided by: dpkg_1.16.1.2ubuntu7_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.

              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.

              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).

              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

       --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.

              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.

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

       --foreign-architecture architecture
              Add architecture to the list of architectures for which packages can  be  installed
              without  using  --force-architecture, in addition to the architecture dpkg is built
              for (i.e.: the output of --print-architecture).

              Print a space-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:  <
              << <= = >= >> >.

       --command-fd n
              Accept  a  series  of commands on input file descriptor n. Note: additional options
              set on the command line, and through  this  file  descriptor,  are  not  reset  for
              subsequent commands executed during the same run.

       --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 the files 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 dashes) 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: Always install a missing conffile. This is dangerous, since it means  not
              preserving a change (removing) made to the file.

              confnew:  If  a  conffile  has been modified 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  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 always choose the default action. 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.

       --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.


              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:








       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 package name being

              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).


       To list packages related to the editor vi(1):
            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 install it there 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).


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


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