dpkg(1) — Linux manual page


dpkg(1)                          dpkg suite                          dpkg(1)

NAME         top

       dpkg - package manager for Debian

SYNOPSIS         top

       dpkg [option...] action

WARNING         top

       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

DESCRIPTION         top

       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

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

              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 correctly unpacked and configured.

   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).

              The package selection is unknown.  A package that is also in a
              not-installed state, and with an ok flag will be forgotten in
              the next database store.

   Package flags
       ok     A package marked ok is in a known state, but might need
              further processing.

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

ACTIONS         top

       -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

       --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 configured.

              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

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

       --triggers-only package...|-a|--pending
              Processes only triggers (since dpkg 1.14.17).  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

       -r, --remove package...|-a|--pending
              Remove an installed package.  This removes everything except
              conffiles and other data cleaned up by the postrm script,
              which 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).  If there is no
              DEBIAN/conffiles control file nor DEBIAN/postrm script, this
              command is equivalent to calling --purge.  If -a or --pending
              is given instead of a package name, then all packages
              unpacked, but marked to be removed in file
              /usr/local/var/lib/dpkg/status, are removed.

              Removing of a package consists of the following steps:

              1. Run prerm script

              2. Remove the installed files

              3. Run postrm script

       -P, --purge package...|-a|--pending
              Purge an installed or already removed package. This removes
              everything, including conffiles, and anything else cleaned up
              from postrm.  If -a or --pending is given instead of a package
              name, then all packages unpacked or removed, but marked to be
              purged in file /usr/local/var/lib/dpkg/status, are purged.

              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

              Purging of a package consists of the following steps:

              1. Remove the package, if not already removed. See --remove
              for detailed information about how this is done.

              2. Run postrm script.

       -V, --verify [package-name...]
              Verifies the integrity of package-name or all packages if
              omitted, by comparing information from the files installed by
              a package with the files metadata information stored in the
              dpkg database (since dpkg 1.17.2).  The origin of the files
              metadata information in the database is the binary packages
              themselves. That metadata gets collected at package unpack
              time during the installation process.

              Currently the only functional check performed is an md5sum
              verification of the file contents against the stored value in
              the files database.  It will only get checked if the database
              contains the file md5sum. To check for any missing metadata in
              the database, the --audit command can be used.

              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

       -C, --audit [package-name...]
              Performs database sanity and consistency checks for package-
              name or all packages if omitted (per package checks since dpkg
              1.17.10).  For example, searches for packages that have been
              installed only partially on your system or that have missing,
              wrong or obsolete control data or files. dpkg will suggest
              what to do with them to get them fixed.

       --update-avail [Packages-file]
       --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». If the
              Packages-file argument is missing or named «-» then it will be
              read from standard input (since dpkg 1.17.7). dpkg keeps its
              record of available packages in

              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

       -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 packages (since dpkg 1.15.4), but only
              those that do not contain user information such as package

              Erase the existing information about what packages are

       --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 shown.

              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 (since dpkg 1.13.18).  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.

              Note: This command makes use of both the available file and
              the package selections.

              Print a single package which is the target of one or more
              relevant pre-dependencies and has itself no unsatisfied pre-

              If such a package is present, output it as a Packages file
              entry, which can be massaged as appropriate.

              Note: This command makes use of both the available file and
              the package selections.

              Returns 0 when a package is printed, 1 when no suitable
              package is available and 2 on error.

       --add-architecture architecture
              Add architecture to the list of architectures for which
              packages can be installed without using --force-architecture
              (since dpkg 1.16.2).  The architecture dpkg is built for (i.e.
              the output of --print-architecture) is always part of that

       --remove-architecture architecture
              Remove architecture from the list of architectures for which
              packages can be installed without using --force-architecture
              (since dpkg 1.16.2). 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,

              Print a newline-separated list of the extra architectures dpkg
              is configured to allow packages to be installed for (since
              dpkg 1.16.2).

              Asserts that dpkg supports the requested feature.  Returns 0
              if the feature is fully supported, 1 if the feature is known
              but dpkg cannot provide support for it yet, and 2 if the
              feature is unknown.  The current list of assertable features

                     Supports the Pre-Depends field (since dpkg 1.1.0).

                     Supports epochs in version strings (since dpkg

                     Supports long filenames in deb(5) archives (since dpkg

                     Supports multiple Conflicts and Replaces (since dpkg

                     Supports multi-arch fields and semantics (since dpkg

                     Supports versioned Provides (since dpkg 1.17.11).

       --validate-thing string
              Validate that the thing string has a correct syntax (since
              dpkg 1.18.16).  Returns 0 if the string is valid, 1 if the
              string is invalid but might be accepted in lax contexts, and 2
              if the string is invalid.  The current list of validatable
              things is:

                     Validates the given package name (since dpkg 1.18.16).

                     Validates the given trigger name (since dpkg 1.18.16).

                     Validates the given architecture name (since dpkg

                     Validates the given version (since dpkg 1.18.16).

       --compare-versions ver1 op ver2
              Compare version numbers, where op is a binary operator. dpkg
              returns true (0) if the specified condition is satisfied, and
              false (1) 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: < << <= = >= >> >. The < and >
              operators are obsolete and should not be used, due to
              confusing semantics. To illustrate: 0.1 < 0.1 evaluates to

       -?, --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

              -b, --build directory [archive|directory]
                  Build a deb package.
              -c, --contents archive
                  List contents of a deb package.
              -e, --control archive [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.
              --ctrl-tarfile archive
                  Output the control tar-file contained in a Debian package.
              --fsys-tarfile archive
                  Output 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

              -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
                  /usr/local/var/lib/dpkg/available. Users of APT-based frontends
                  should use apt-cache show package-name instead.

OPTIONS         top

       All options can be specified both on the command line and in the dpkg
       configuration file /usr/local/etc/dpkg/dpkg.cfg or fragment files
       (with names matching this shell pattern '[0-9a-zA-Z_-]*') on the
       configuration directory /usr/local/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

       -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-oring 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

       --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.  This
              affects the Pre-Depends and Depends fields.

              depends-version: Don't care about versions when checking
              dependencies.  This affects the Pre-Depends and Depends

              breaks: Install, even if this would break another package
              (since dpkg 1.14.6).  This affects the Breaks field.

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

              confmiss: 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 (since dpkg 1.15.8).  If
              any of --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.

              statoverride-add: Overwrite an existing stat override when
              adding it (since dpkg 1.19.5).

              statoverride-remove: Ignore a missing stat override when
              removing it (since dpkg 1.19.5).

              security-mac(*): Use platform-specific Mandatory Access
              Controls (MAC) based security when installing files into the
              filesystem (since dpkg 1.19.5).  On Linux systems the
              implementation uses SELinux.

              unsafe-io: Do not perform safe I/O operations when unpacking
              (since dpkg  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

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

              script-chrootless: Run maintainer scripts without chroot(2)ing
              into instdir even if the package does not support this mode of
              operation (since dpkg 1.18.5).

              Warning: This can destroy your host system, use with extreme

              architecture: Process even packages with wrong or no

              bad-version: Process even packages with wrong versions (since
              dpkg 1.16.1).

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

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

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

              Ignore dependency-checking for specified packages (actually,
              checking is performed, but only warnings about conflicts are
              given, nothing else).  This affects the Pre-Depends, Depends
              and Breaks fields.

       --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 anything.

              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
              --record-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.

              Set the administrative directory to directory.  This directory
              contains many files that give information about status of
              installed or uninstalled packages, etc.  Defaults to

              Set the 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 «/».

              Set the root directory to directory, which sets the
              installation directory to «dir» and the administrative
              directory to «dir/usr/local/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, purge, add-architecture and
              remove-architecture dpkg actions (since dpkg 1.15.4;
              add-architecture and remove-architecture actions since dpkg
              1.17.19). 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 (since dpkg 1.15.8).

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

              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 is:


              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

              The filters are applied when unpacking the binary packages,
              and as such only have knowledge of the type of object
              currently being filtered (e.g. a normal file or a directory)
              and have not visibility of what objects will come next.
              Because these filters have side effects (in contrast to
              find(1) filters), excluding an exact pathname that happens to
              be a directory object like /usr/share/doc will not have the
              desired result, and only that pathname will be excluded (which
              could be automatically reincluded if the code sees the need).
              Any subsequent files contained within that directory will fail
              to unpack.

              Hint: make sure the globs are not expanded by your shell.

       --verify-format format-name
              Sets the output format for the --verify command (since dpkg

              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 each specific check
              result, 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 md5sum verification failure (the file contents have
              changed) is 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

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

              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, to be run via “sh -c”
              (since dpkg 1.16.0).  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 /usr/local/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 startup type command
                     For each dpkg invocation where type is archives (with a
                     command of unpack or install) or packages (with a
                     command of configure, triggers-only, remove or purge).

              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-
                     For actions where action is one of install, upgrade,
                     configure, trigproc, disappear, remove or purge.

              YYYY-MM-DD HH:MM:SS conffile filename decision
                     For conffile changes where decision is either install
                     or keep.

              Disables the use of any pager when showing information (since
              dpkg 1.19.2).

              Do not try to verify package signatures.

              Do not run any triggers in this run (since dpkg 1.14.17), but
              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 (since dpkg 1.14.17).

EXIT STATUS         top

       0      The requested action was successfully performed.  Or a check
              or assertion command returned true.

       1      A check or assertion command returned false.

       2      Fatal or unrecoverable error due to invalid command-line
              usage, or interactions with the system, such as accesses to
              the database, memory allocations, etc.

ENVIRONMENT         top

   External environment
       PATH   This variable is expected to be defined in the environment and
              point to the system paths where several required programs are
              to be found. If it's not set or the programs are not found,
              dpkg will abort.

       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 directories.

       SHELL  The program dpkg will execute when starting a new interactive
              shell, or when spawning a command via a shell.

              The program dpkg will execute when running a pager, for
              example when displaying the conffile differences.  If SHELL is
              not set, «sh» will be used instead.  The DPKG_PAGER overrides
              the PAGER environment variable (since dpkg 1.19.2).

              Sets the color mode (since dpkg 1.18.5).  The currently
              accepted values are: auto (default), always and never.

              Sets the force flags (since dpkg 1.19.5).  When this variable
              is present, no built-in force defaults will be applied.  If
              the variable is present but empty, all force flags will be

              Set by a package manager frontend to notify dpkg that it
              should not acquire the frontend lock (since dpkg 1.19.1).

   Internal environment
       LESS   Defined by dpkg to “-FRSXMQ”, if not already set, when
              spawning a pager (since dpkg 1.19.2).  To change the default
              behavior, this variable can be preset to some other value
              including an empty string, or the PAGER or DPKG_PAGER
              variables can be set to disable specific options with «-+»,
              for example DPKG_PAGER="less -+F".

              Defined by dpkg on the maintainer script environment to
              indicate which installation to act on (since dpkg 1.18.5).
              The value is intended to be prepended to any path maintainer
              scripts operate on.  During normal operation, this variable is
              empty.  When installing packages into a different instdir,
              dpkg normally invokes maintainer scripts using chroot(2) and
              leaves this variable empty, but if --force-script-chrootless
              is specified then the chroot(2) call is skipped and instdir is

              Defined by dpkg on the maintainer script environment to
              indicate the dpkg administrative directory to use (since dpkg
              1.16.0).  This variable is always set to the current
              --admindir value.

              Defined by dpkg on the subprocesses environment to all the
              currently enabled force option names separated by commas
              (since dpkg 1.19.5).

              Defined by dpkg on the shell spawned on the conffile prompt to
              examine the situation (since dpkg 1.15.6).  Current valid
              value: conffile-prompt.

              Defined by dpkg on the shell spawned on the conffile prompt to
              examine the situation (since dpkg 1.15.6).  Contains the path
              to the old conffile.

              Defined by dpkg on the shell spawned on the conffile prompt to
              examine the situation (since dpkg 1.15.6).  Contains the path
              to the new conffile.

              Defined by dpkg on the shell spawned when executing a hook
              action (since dpkg 1.15.4).  Contains the current dpkg action.

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

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

              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 (since dpkg 1.15.4).

              Defined by dpkg on the maintainer script environment to the
              name of the script running, one of preinst, postinst, prerm or
              postrm (since dpkg 1.15.7).

              Defined by dpkg on the maintainer script environment to a
              value (‘0’ or ‘1’) noting whether debugging has been requested
              (with the --debug option) for the maintainer scripts (since
              dpkg 1.18.4).

FILES         top

              Configuration fragment files (since dpkg 1.15.4).

              Configuration file with default options.

              Default log file (see /usr/local/etc/dpkg/dpkg.cfg and option

       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 format and contents of a binary package are described in deb(5).

BUGS         top

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

EXAMPLES         top

       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 /usr/local/var/lib/dpkg/available of two
            dpkg --print-avail elvis vim | less

       To search the listing of packages yourself:
            less /usr/local/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
            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 https://wiki.debian.org/Teams/Dpkg/FAQ for more
       details), for example:
            apt-cache dumpavail | dpkg --merge-avail
       or with dpkg 1.17.6 and earlier:
            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.

SEE ALSO         top

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

AUTHORS         top

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

COLOPHON         top

       This page is part of the dpkg (Debian Package Manager) project.
       Information about the project can be found at 
       ⟨https://wiki.debian.org/Teams/Dpkg/⟩.  If you have a bug report for
       this manual page, see
       ⟨http://bugs.debian.org/cgi-bin/pkgreport.cgi?src=dpkg⟩.  This page
       was obtained from the project's upstream Git repository
       ⟨https://salsa.debian.org/dpkg-team/dpkg.git⟩ on 2020-08-13.  (At
       that time, the date of the most recent commit that was found in the
       repository was 2020-07-08.)  If you discover any rendering problems
       in this HTML version of the page, or you believe there is a better or
       more up-to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not part
       of the original manual page), send a mail to man-pages@man7.org

1.19.6-2-g6e42d5                 2019-03-25                          dpkg(1)

Pages that refer to this page: dpkg-architecture(1)dpkg-deb(1)dpkg-divert(1)dpkg-name(1)dpkg-query(1)dpkg-scanpackages(1)dpkg-split(1)dpkg-statoverride(1)dpkg-trigger(1)dselect(1)deb-conffiles(5)deb-control(5)deb-postinst(5)deb-postrm(5)deb-preinst(5)deb-prerm(5)deb-substvars(5)deb-triggers(5)dpkg.cfg(5)deb-version(7)