Adding upstream version 1.21.22.upstream/1.21.22upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1488 insertions, 0 deletions

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+# dpkg manual page - dpkg(1)
+#
+# Copyright © 1996 Juho Vuori <javuori@cc.helsinki.fi>
+# Copyright © 1999 Jim Van Zandt <jrv@vanzandt.mv.com>
+# Copyright © 1999-2003 Wichert Akkerman <wakkerma@debian.org>
+# Copyright © 2000-2003 Adam Heath <doogie@debian.org>
+# Copyright © 2002 Josip Rodin
+# Copyright © 2004-2005 Scott James Remnant <keybuk@debian.org>
+# Copyright © 2006-2016 Guillem Jover <guillem@debian.org>
+# Copyright © 2007-2008 Ian Jackson <ijackson@chiark.greenend.org.uk>
+# Copyright © 2008-2011 Raphaël Hertzog <hertzog@debian.org>
+#
+# This is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+=encoding utf8
+
+=head1 NAME
+
+dpkg - package manager for Debian
+
+=head1 SYNOPSIS
+
+B<dpkg>
+[I<option>...] I<action>
+
+=head1 WARNING
+
+This manual is intended for users wishing to understand B<dpkg>'s
+command line options and package states in more detail than that
+provided by B<dpkg --help>.
+
+It should I<not> be used by package maintainers wishing to
+understand how B<dpkg> will install their packages. The
+descriptions of what B<dpkg> does when installing and removing
+packages are particularly inadequate.
+
+=head1 DESCRIPTION
+
+B<dpkg> is a medium-level tool to install, build, remove and manage
+Debian packages.
+The primary and more user-friendly front-end for B<dpkg>
+as a CLI (command-line interface) is B<apt>(8) and
+as a TUI (terminal user interface) is B<aptitude>(8).
+B<dpkg> itself is
+controlled entirely via command line parameters, which consist of exactly
+one action and zero or more options. The action-parameter tells B<dpkg>
+what to do and options control the behavior of the action in some way.
+
+B<dpkg> can also be used as a front-end to B<dpkg-deb>(1) and
+B<dpkg-query>(1). The list of supported actions can be found later on
+in the B<ACTIONS> section. If any such action is encountered B<dpkg>
+just runs B<dpkg-deb> or B<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.
+
+=head1 INFORMATION ABOUT PACKAGES
+
+B<dpkg> maintains some usable information about available
+packages. The information is divided in three classes: B<states>,
+B<selection states> and B<flags>. These values are intended to
+be changed mainly with B<dselect>.
+
+=head2 Package states
+
+=over
+
+=item B<not-installed>
+
+The package is not installed on your system.
+
+=item B<config-files>
+
+Only the configuration files or the B<postrm> script and the data it needs
+to remove of the package exist on the system.
+
+=item B<half-installed>
+
+The installation of the package has been started, but not completed for
+some reason.
+
+=item B<unpacked>
+
+The package is unpacked, but not configured.
+
+=item B<half-configured>
+
+The package is unpacked and configuration has been started, but not yet
+completed for some reason.
+
+=item B<triggers-awaited>
+
+The package awaits trigger processing by another package.
+
+=item B<triggers-pending>
+
+The package has been triggered.
+
+=item B<installed>
+
+The package is correctly unpacked and configured.
+
+=back
+
+=head2 Package selection states
+
+=over
+
+=item B<install>
+
+The package is selected for installation.
+
+=item B<hold>
+
+A package marked to be on B<hold> is kept on the same version, that is,
+no automatic new installs, upgrades or removals will be performed on them,
+unless these actions are requested explicitly, or are permitted to be done
+automatically with the B<--force-hold> option.
+
+=item B<deinstall>
+
+The package is selected for deinstallation (i.e. we want to remove all
+files, except configuration files).
+
+=item B<purge>
+
+The package is selected to be purged (i.e. we want to remove everything
+from system directories, even configuration files).
+
+=item B<unknown>
+
+The package selection is unknown.
+A package that is also in a B<not-installed> state, and with an
+B<ok> flag will be forgotten in the next database store.
+
+=back
+
+=head2 Package flags
+
+=over
+
+=item B<ok>
+
+A package marked B<ok> is in a known state, but might need further
+processing.
+
+=item B<reinstreq>
+
+A package marked B<reinstreq> is broken and requires
+reinstallation. These packages cannot be removed, unless forced with
+option B<--force-remove-reinstreq>.
+
+=back
+
+=head1 ACTIONS
+
+=over
+
+=item B<-i>, B<--install> I<package-file>...
+
+Install the package. If B<--recursive> or B<-R> option is
+specified, I<package-file> must refer to a directory instead.
+
+Installation consists of the following steps:
+
+B<1.> Extract the control files of the new package.
+
+B<2.> If another version of the same package was installed before
+the new installation, execute I<prerm> script of the old package.
+
+B<3.> Run I<preinst> script, if provided by the package.
+
+B<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.
+
+B<5.> If another version of the same package was installed before
+the new installation, execute the I<postrm> script of the old
+package. Note that this script is executed after the I<preinst>
+script of the new package, because new files are written at the same
+time old files are removed.
+
+B<6.> Configure the package. See B<--configure> for detailed
+information about how this is done.
+
+=item B<--unpack> I<package-file>...
+
+Unpack the package, but don't configure it. If B<--recursive> or
+B<-R> option is specified, I<package-file> must refer to a
+directory instead.
+
+Will process triggers for B<Pre-Depends> unless B<--no-triggers> has
+been specified.
+
+=item B<--configure> I<package>...|B<-a>|B<--pending>
+
+Configure a package which has been unpacked but not yet configured.
+If B<-a> or B<--pending> is given instead of I<package>,
+all unpacked but unconfigured packages are configured.
+
+To reconfigure a package which has already been configured, try the
+B<dpkg-reconfigure>(8)
+command instead.
+
+Configuring consists of the following steps:
+
+B<1.> Unpack the conffiles, and at the same time back up
+the old conffiles, so that they can be restored if
+something goes wrong.
+
+B<2.> Run I<postinst> script, if provided by the package.
+
+Will process triggers unless B<--no-triggers> has been specified.
+
+=item B<--triggers-only> I<package>...|B<-a>|B<--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 B<triggers-awaited> and B<triggers-pending> states. This
+can be fixed later by running: B<dpkg --configure --pending>.
+
+=item B<-r>, B<--remove> I<package>...|B<-a>|B<--pending>
+
+Remove an installed package.
+This removes everything except conffiles and other data cleaned up by
+the I<postrm> script,
+which may avoid having to reconfigure the package if it is reinstalled
+later (conffiles are configuration files that are listed in the
+I<DEBIAN/conffiles> control file).
+If there is no I<DEBIAN/conffiles> control file nor I<DEBIAN/postrm>
+script, this command is equivalent to calling B<--purge>.
+If B<-a> or B<--pending> is given instead of a package name,
+then all packages unpacked, but marked to be removed in file
+I<%ADMINDIR%/status>, are removed.
+
+Removing of a package consists of the following steps:
+
+B<1.> Run I<prerm> script
+
+B<2.> Remove the installed files
+
+B<3.> Run I<postrm> script
+
+Will process triggers unless B<--no-triggers> has been specified.
+
+=item B<-P>, B<--purge> I<package>...|B<-a>|B<--pending>
+
+Purge an installed or already removed package. This removes everything,
+including conffiles, and anything else cleaned up from I<postrm>.
+If B<-a> or B<--pending> is given instead of a package name,
+then all packages unpacked or removed, but marked to be purged in file
+I<%ADMINDIR%/status>, are purged.
+
+B<Note:> Some configuration files might be unknown to B<dpkg> because they
+are created and handled separately through the configuration scripts. In
+that case, B<dpkg> won't remove them by itself, but the package's
+I<postrm> script (which is called by B<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.
+
+Purging of a package consists of the following steps:
+
+B<1.> Remove the package, if not already removed. See B<--remove>
+for detailed information about how this is done.
+
+B<2.> Run I<postrm> script.
+
+Will process triggers unless B<--no-triggers> has been specified.
+
+=item B<-V>, B<--verify> [I<package-name>...]
+
+Verifies the integrity of I<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 B<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 B<--audit> command can be used.
+
+The output format is selectable with the B<--verify-format>
+option, which by default uses the B<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.
+
+=item B<-C>, B<--audit> [I<package-name>...]
+
+Performs database sanity and consistency checks for I<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. B<dpkg> will suggest what to do with them to get them fixed.
+
+=item B<--update-avail> [I<Packages-file>]
+
+=item B<--merge-avail> [I<Packages-file>]
+
+Update B<dpkg>'s and B<dselect>'s idea of which packages are
+available. With action B<--merge-avail>, old information is
+combined with information from I<Packages-file>. With action
+B<--update-avail>, old information is replaced with the information
+in the I<Packages-file>. The I<Packages-file> distributed with
+Debian is simply named «I<Packages>». If the I<Packages-file>
+argument is missing or named «B<->» then it will be read from
+standard input (since dpkg 1.17.7). B<dpkg> keeps its record of
+available packages in I<%ADMINDIR%/available>.
+
+A simpler one-shot command to retrieve and update the I<available>
+file is B<dselect update>. Note that this file is mostly useless
+if you don't use B<dselect> but an APT-based frontend: APT has its
+own system to keep track of available packages.
+
+=item B<-A>, B<--record-avail> I<package-file>...
+
+Update B<dpkg> and B<dselect>'s idea of which packages are
+available with information from the package I<package-file>. If
+B<--recursive> or B<-R> option is specified, I<package-file>
+must refer to a directory instead.
+
+=item B<--forget-old-unavail>
+
+Now B<obsolete> and a no-op as B<dpkg> will automatically forget
+uninstalled unavailable packages (since dpkg 1.15.4), but only those that
+do not contain user information such as package selections.
+
+=item B<--clear-avail>
+
+Erase the existing information about what packages are available.
+
+=item B<--get-selections> [I<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.
+
+=item B<--set-selections>
+
+Set package selections using file read from stdin. This file should be
+in the format “I<package> I<state>”, where state is one of
+B<install>, B<hold>, B<deinstall> or B<purge>. Blank lines
+and comment lines beginning with ‘B<#>’ are also permitted.
+
+The I<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 B<--update-avail> and B<--merge-avail> commands for more
+information.
+
+=item B<--clear-selections>
+
+Set the requested state of every non-essential package to deinstall
+(since dpkg 1.13.18).
+This is intended to be used immediately before B<--set-selections>,
+to deinstall any packages not in list given to B<--set-selections>.
+
+=item B<--yet-to-unpack>
+
+Searches for packages selected for installation, but which for some
+reason still haven't been installed.
+
+B<Note:> This command makes use of both the available file and the package
+selections.
+
+=item B<--predep-package>
+
+Print a single package which is the target of one or more relevant
+pre-dependencies and has itself no unsatisfied pre-dependencies.
+
+If such a package is present, output it as a Packages file entry,
+which can be massaged as appropriate.
+
+B<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.
+
+=item B<--add-architecture> I<architecture>
+
+Add I<architecture> to the list of architectures for which packages can
+be installed without using B<--force-architecture> (since dpkg 1.16.2).
+The architecture
+B<dpkg> is built for (i.e. the output of B<--print-architecture>)
+is always part of that list.
+
+=item B<--remove-architecture> I<architecture>
+
+Remove I<architecture> from the list of architectures for which packages
+can be installed without using B<--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 B<--force-architecture> is specified. The
+architecture B<dpkg> is built for (i.e. the output of
+B<--print-architecture>) can never be removed from that list.
+
+=item B<--print-architecture>
+
+Print architecture of packages B<dpkg> installs (for example, “i386”).
+
+=item B<--print-foreign-architectures>
+
+Print a newline-separated list of the extra architectures B<dpkg> is
+configured to allow packages to be installed for (since dpkg 1.16.2).
+
+=item B<--assert-help>
+
+Give help about the B<--assert->I<feature> options (since dpkg 1.21.0).
+
+=item B<--assert->I<feature>
+
+Asserts that B<dpkg> supports the requested feature.
+Returns 0 if the feature is fully supported, 1 if the feature is known but
+B<dpkg> cannot provide support for it yet, and 2 if the feature is unknown.
+The current list of assertable features is:
+
+=over
+
+=item B<support-predepends>
+
+Supports the B<Pre-Depends> field (since dpkg 1.1.0).
+
+=item B<working-epoch>
+
+Supports epochs in version strings (since dpkg 1.4.0.7).
+
+=item B<long-filenames>
+
+Supports long filenames in B<deb>(5) archives (since dpkg 1.4.1.17).
+
+=item B<multi-conrep>
+
+Supports multiple B<Conflicts> and B<Replaces> (since dpkg 1.4.1.19).
+
+=item B<multi-arch>
+
+Supports multi-arch fields and semantics (since dpkg 1.16.2).
+
+=item B<versioned-provides>
+
+Supports versioned B<Provides> (since dpkg 1.17.11).
+
+=item B<protected-field>
+
+Supports the B<Protected> field (since dpkg 1.20.1).
+
+=back
+
+=item B<--validate->I<thing> I<string>
+
+Validate that the I<thing> I<string> has a correct syntax
+(since dpkg 1.18.16).
+Returns 0 if the I<string> is valid, 1 if the I<string> is invalid but
+might be accepted in lax contexts, and 2 if the I<string> is invalid.
+The current list of validatable I<thing>s is:
+
+=over
+
+=item B<pkgname>
+
+Validates the given package name (since dpkg 1.18.16).
+
+=item B<trigname>
+
+Validates the given trigger name (since dpkg 1.18.16).
+
+=item B<archname>
+
+Validates the given architecture name (since dpkg 1.18.16).
+
+=item B<version>
+
+Validates the given version (since dpkg 1.18.16).
+
+=back
+
+=item B<--compare-versions> I<ver1> I<op> I<ver2>
+
+Compare version numbers, where I<op> is a binary operator. B<dpkg>
+returns true (B<0>) if the specified condition is satisfied,
+and false (B<1>) otherwise. There are
+two groups of operators, which differ in how they treat an empty
+I<ver1> or I<ver2>. These treat an empty version as earlier than any
+version: B<lt le eq ne ge gt>. These treat an empty version as later
+than any version: B<lt-nl le-nl ge-nl gt-nl>. These are provided
+only for compatibility with control file syntax: B<E<lt> E<lt>E<lt> E<lt>= = E<gt>= E<gt>E<gt>
+E<gt>>. The B<E<lt>> and B<E<gt>> operators are obsolete and should B<not>
+be used, due to confusing semantics. To illustrate: B<0.1 E<lt> 0.1>
+evaluates to true.
+
+=begin disabled
+
+=item B<--command-fd> I<n>
+
+Accept a series of commands on input file descriptor I<n>.
+
+B<Note:> Additional options set on the command line, and through this
+file descriptor, are not reset for subsequent commands executed during the
+same run.
+
+=end disabled
+
+=item B<-?>, B<--help>
+
+Display a brief help message.
+
+=item B<--force-help>
+
+Give help about the B<--force->I<thing> options.
+
+=item B<-Dh>, B<--debug=help>
+
+Give help about debugging options.
+
+=item B<--version>
+
+Display B<dpkg> version information.
+
+When used with B<--robot>, the output will be the program version number
+in a dotted numerical format, with no newline.
+
+=item B<dpkg-deb actions>
+
+See B<dpkg-deb>(1) for more information about the following actions,
+and other actions and options not exposed by the B<dpkg> front-end.
+
+=over
+
+=item B<-b>, B<--build> I<directory> [I<archive>|I<directory>]
+
+Build a deb package.
+
+=item B<-c>, B<--contents> I<archive>
+
+List contents of a deb package.
+
+=item B<-e>, B<--control> I<archive> [I<directory>]
+
+Extract control-information from a package.
+
+=item B<-x>, B<--extract> I<archive> I<directory>
+
+Extract the files contained by package.
+
+=item B<-X>, B<--vextract> I<archive> I<directory>
+
+Extract and display the filenames contained by a package.
+
+=item B<-f>, B<--field>  I<archive> [I<control-field>...]
+
+Display control field(s) of a package.
+
+=item B<--ctrl-tarfile> I<archive>
+
+Output the control tar-file contained in a Debian package.
+
+=item B<--fsys-tarfile> I<archive>
+
+Output the filesystem tar-file contained by a Debian package.
+
+=item B<-I>, B<--info> I<archive> [I<control-file>...]
+
+Show information about a package.
+
+=back
+
+=item B<dpkg-query actions>
+
+See B<dpkg-query>(1) for more information about the following actions,
+and other actions and options not exposed by the B<dpkg> front-end.
+
+=over
+
+=item B<-l>, B<--list> I<package-name-pattern>...
+
+List packages matching given pattern.
+
+=item B<-s>, B<--status> I<package-name>...
+
+Report status of specified package.
+
+=item B<-L>, B<--listfiles> I<package-name>...
+
+List files installed to your system from I<package-name>.
+
+=item B<-S>, B<--search> I<filename-search-pattern>...
+
+Search for a filename from installed packages.
+
+=item B<-p>, B<--print-avail> I<package-name>...
+
+Display details about I<package-name>, as found in
+I<%ADMINDIR%/available>. Users of APT-based frontends
+should use B<apt show> I<package-name> instead.
+
+=back
+
+=back
+
+=head1 OPTIONS
+
+All options can be specified both on the command line and in the B<dpkg>
+configuration file I<%PKGCONFDIR%/dpkg.cfg> or fragment files (with names
+matching this shell pattern '[0-9a-zA-Z_-]*') on the configuration
+directory I<%PKGCONFDIR%/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 ‘B<#>’).
+
+=over
+
+=item B<--abort-after=>I<number>
+
+Change after how many errors B<dpkg> will abort. The default is 50.
+
+=item B<-B>, 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.
+
+=item B<-D>I<octal>, B<--debug=>I<octal>
+
+Switch debugging on. I<octal> is formed by bitwise-ORing desired
+values together from the list below (note that these values may change
+in future releases). B<-Dh> or B<--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 for example the dpkg/info dir
+      2000   Insane amounts of drivel
+
+=item B<--force->I<things>
+
+=item B<--no-force->I<things>, B<--refuse->I<things>
+
+Force or refuse (B<no-force> and B<refuse> mean the same thing)
+to do some things. I<things> is a comma separated list of things
+specified below. B<--force-help> displays a message describing them.
+Things marked with (*) are forced by default.
+
+I<Warning: These options are mostly intended to be used by experts
+only. Using them without fully understanding their effects may break
+your whole system.>
+
+B<all>:
+Turns on (or off) all force options.
+
+B<downgrade>(*):
+Install a package, even if newer version of it is already installed.
+
+I<Warning: At present> B<dpkg> I<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.>
+
+B<configure-any>:
+Configure also any unpacked but unconfigured packages on which the current
+package depends.
+
+B<hold>:
+Allow automatic installs, upgrades or removals of packages even when marked
+to be on “hold”.
+B<Note:> When these actions are requested explicitly, the “hold” package
+selection state always gets ignored.
+
+B<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 B<dpkg>.
+
+B<remove-protected>:
+Remove, even if the package is considered protected (since dpkg 1.20.1).
+Protected packages contain mostly important system boot infrastructure or
+are used for custom system-local meta-packages.
+Removing them might cause the whole system to be unable to boot or lose
+required functionality to operate, so use with caution.
+
+B<remove-essential>:
+Remove, even if the package is considered essential.
+Essential packages contain mostly very basic Unix commands, required for
+the packaging system, for the operation of the system in general or during
+boot (although the latter should be converted to protected packages instead).
+Removing them might cause the whole system to stop working,
+so use with caution.
+
+B<depends>:
+Turn all dependency problems into warnings.
+This affects the B<Pre-Depends> and B<Depends> fields.
+
+B<depends-version>:
+Don't care about versions when checking dependencies.
+This affects the B<Pre-Depends> and B<Depends> fields.
+
+B<breaks>:
+Install, even if this would break another package (since dpkg 1.14.6).
+This affects the B<Breaks> field.
+
+B<conflicts>:
+Install, even if it conflicts with another package. This is dangerous,
+for it will usually cause overwriting of some files.
+This affects the B<Conflicts> field.
+
+B<confmiss>:
+Always install the missing conffile without prompting. This is dangerous,
+since it means not preserving a change (removing) made to the file.
+
+B<confnew>:
+If a conffile has been modified and the version in the package did change,
+always install the new version without prompting, unless the
+B<--force-confdef> is also specified, in which case the default
+action is preferred.
+
+B<confold>:
+If a conffile has been modified and the version in the package did change,
+always keep the old version without prompting, unless the
+B<--force-confdef> is also specified, in which case the default
+action is preferred.
+
+B<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 B<--force-confnew> or
+B<--force-confold> is also been given, in which case it will use
+that to decide the final action.
+
+B<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 B<--force-confnew>,
+B<--force-confold>, or B<--force-confdef> is also given,
+it will be used to decide the final action.
+
+B<overwrite>:
+Overwrite one package's file with another's file.
+
+B<overwrite-dir>:
+Overwrite one package's directory with another's file.
+
+B<overwrite-diverted>:
+Overwrite a diverted file with an undiverted version.
+
+B<statoverride-add>:
+Overwrite an existing stat override when adding it (since dpkg 1.19.5).
+
+B<statoverride-remove>:
+Ignore a missing stat override when removing it (since dpkg 1.19.5).
+
+B<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.
+
+B<unsafe-io>:
+Do not perform safe I/O operations when unpacking (since dpkg 1.15.8.6).
+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.
+
+I<Note>: For ext4, the main offender, consider using instead the
+mount option B<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.
+
+I<Warning: Using this option might improve performance at the cost of
+losing data, use with care.>
+
+B<script-chrootless>:
+Run maintainer scripts without B<chroot>(2)ing into B<instdir> even
+if the package does not support this mode of operation (since dpkg 1.18.5).
+
+I<Warning: This can destroy your host system, use with extreme care.>
+
+B<architecture>:
+Process even packages with wrong or no architecture.
+
+B<bad-version>:
+Process even packages with wrong versions (since dpkg 1.16.1).
+
+B<bad-path>:
+B<PATH> is missing important programs, so problems are likely.
+
+B<not-root>:
+Try to (de)install things even when not root.
+
+B<bad-verify>:
+Install a package even if it fails authenticity check.
+
+=item B<--ignore-depends>=I<package>,...
+
+Ignore dependency-checking for specified packages (actually, checking is
+performed, but only warnings about conflicts are given, nothing else).
+This affects the B<Pre-Depends>, B<Depends> and B<Breaks> fields.
+
+=item B<--no-act>, B<--dry-run>, B<--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 B<--no-act> before the action-parameter, or you might
+end up with undesirable results. (e.g. B<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).
+
+=item B<-R>, B<--recursive>
+
+Recursively handle all regular files matching pattern B<*.deb>
+found at specified directories and all of its subdirectories. This can
+be used with B<-i>, B<-A>, B<--install>, B<--unpack> and
+B<--record-avail> actions.
+
+=item B<-G>
+
+Don't install a package if a newer version of the same package is already
+installed. This is an alias of B<--refuse-downgrade>.
+
+=item B<--admindir=>I<dir>
+
+Set the administrative directory to I<directory>.
+This directory contains many files that give information about status of
+installed or uninstalled packages, etc.
+Defaults to «I<%ADMINDIR%>» if B<DPKG_ADMINDIR> has not been set.
+
+=item B<--instdir=>I<dir>
+
+Set the installation directory, which refers to the directory where
+packages are to be installed. B<instdir> is also the directory passed
+to B<chroot>(2) before running package's installation scripts, which
+means that the scripts see B<instdir> as a root directory.
+Defaults to «I</>».
+
+=item B<--root=>I<dir>
+
+Set the root directory to B<directory>, which sets the installation
+directory to «I<dir>» and the administrative
+directory to «I<dir>B<%ADMINDIR%>».
+
+=item B<-O>, B<--selected-only>
+
+Only process the packages that are selected for installation. The
+actual marking is done with B<dselect> or by B<dpkg>, when it
+handles packages. For example, when a package is removed, it will
+be marked selected for deinstallation.
+
+=item B<-E>, B<--skip-same-version>
+
+Don't install the package if the same version and architecture
+of the package is already installed.
+
+Since dpkg 1.21.10, the architecture is also taken into account,
+which makes it possible to cross-grade packages or install additional
+co-installable instances with the same version, but different architecture.
+
+=item B<--pre-invoke=>I<command>
+
+=item B<--post-invoke=>I<command>
+
+Set an invoke hook I<command> to be run via “sh -c” before or
+after the B<dpkg> run for the I<unpack>, I<configure>, I<install>,
+I<triggers-only>, I<remove>, I<purge>, I<add-architecture> and
+I<remove-architecture> B<dpkg> actions (since dpkg 1.15.4;
+I<add-architecture> and I<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 B<DPKG_HOOK_ACTION> is set for the hooks to the
+current B<dpkg> action.
+
+B<Note:> Front-ends might call B<dpkg> several
+times per invocation, which might run the hooks more times than expected.
+
+=item B<--path-exclude=>I<glob-pattern>
+
+=item B<--path-include=>I<glob-pattern>
+
+Set I<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).
+
+I<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, «I</usr/*/READ*>» matches
+«I</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 B<glob>(7) for detailed information about
+globbing.
+B<Note:> The current implementation might re-include more directories
+and symlinks than needed, in particular when there is a more specific
+re-inclusion, 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:
+
+ --path-exclude=/usr/share/doc/*
+ --path-include=/usr/share/doc/*/copyright
+
+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.
+
+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 B<find>(1)
+filters), excluding an exact pathname that happens to be a directory object
+like I</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.
+
+=item B<--verify-format> I<format-name>
+
+Sets the output format for the B<--verify> command (since dpkg 1.17.2).
+
+The only currently supported output format is B<rpm>, which consists
+of a line for every path that failed any check.
+These lines have the following format:
+
+Z<>
+ B<missing  > [B<c>] I<pathname> [B<(>I<error-message>B<)>]
+ B<??5??????> [B<c>] I<pathname>
+
+The first 9 characters are used to report the checks result,
+either a literal B<missing> when the file is not present or its metadata
+cannot be fetched,
+or one of the following special characters that report the result for each
+check:
+
+=over
+
+=item ‘B<?>’
+
+Implies the check could not be done (lack of support, file permissions, etc).
+
+=item ‘B<.>’
+
+Implies the check passed.
+
+=item ‘I<A-Za-z0-9>’
+
+Implies a specific check failed.
+The following positions and alphanumeric characters are currently supported:
+
+=over
+
+=item 1 ‘B<?>’
+
+These checks are currently not supported, will always be ‘B<?>’.
+
+=item 2 ‘B<M>’
+
+The file mode check failed (since dpkg 1.21.0).
+Because pathname metadata is currently not tracked, this check can only be
+partially emulated via a very simple heuristic for pathnames that have a
+known digest, which implies they should be regular files, where the check
+will fail if the pathname is not a regular file on the filesystem.
+This check will currently never succeed as it does not have enough
+information available.
+
+=item 3 ‘B<5>’
+
+The digest check failed, which means the file contents have changed.
+
+=item 4-9 ‘B<?>’
+
+These checks are currently not supported, will always be ‘B<?>’.
+
+=back
+
+=back
+
+The line is followed by a space and an attribute character.
+The following attribute character is supported:
+
+=over
+
+=item ‘B<c>’
+
+The pathname is a conffile.
+
+=back
+
+Finally followed by another space and the pathname.
+
+In case the entry was of the B<missing> type, and the file was not actually
+present on the filesystem, then the line is followed by a space and the
+error message enclosed within parenthesis.
+
+=item B<--status-fd> I<n>
+
+Send machine-readable package status and progress information to file
+descriptor I<n>. This option can be specified multiple times. The
+information is generally one record per line, in one of the following
+forms:
+
+=over
+
+=item B<status:> I<package>B<:> I<status>
+
+Package status changed; I<status> is as in the status file.
+
+=item B<status:> I<package> B<: error :> I<extended-error-message>
+
+An error occurred. Any possible newlines in I<extended-error-message>
+will be converted to spaces before output.
+
+=item B<status:> I<file> B<: conffile-prompt : '>I<real-old>B<' '>I<real-new>B<'> I<useredited> I<distedited>
+
+User is being asked a conffile question.
+
+=item B<processing:> I<stage>B<:> I<package>
+
+Sent just before a processing stage starts. I<stage> is one of
+B<upgrade>, B<install> (both sent before unpacking),
+B<configure>, B<trigproc>, B<disappear>, B<remove>, B<purge>.
+
+=back
+
+=item B<--status-logger>=I<command>
+
+Send machine-readable package status and progress information to the
+shell I<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 B<--status-fd>.
+
+=item B<--log=>I<filename>
+
+Log status change updates and actions to I<filename>, instead of
+the default I<%LOGDIR%/dpkg.log>. If this option is given multiple
+times, the last filename is used. Log messages are of the form:
+
+=over
+
+=item YYYY-MM-DD HH:MM:SS B<startup> I<type> I<command>
+
+For each dpkg invocation where I<type> is B<archives> (with a
+I<command> of B<unpack> or B<install>) or B<packages>
+(with a I<command> of B<configure>, B<triggers-only>,
+B<remove> or B<purge>).
+
+=item YYYY-MM-DD HH:MM:SS B<status> I<state> I<pkg> I<installed-version>
+
+For status change updates.
+
+=item YYYY-MM-DD HH:MM:SS I<action> I<pkg> I<installed-version> I<available-version>
+
+For actions where I<action> is one of B<install>, B<upgrade>,
+B<configure>, B<trigproc>, B<disappear>, B<remove> or B<purge>.
+
+=item YYYY-MM-DD HH:MM:SS B<conffile> I<filename> I<decision>
+
+For conffile changes where I<decision> is either B<install> or
+B<keep>.
+
+=back
+
+=item B<--robot>
+
+Use a machine-readable output format. This provides an interface for programs
+that need to parse the output of some of the commands that do not otherwise
+emit a machine-readable output format. No localization will be used, and the
+output will be modified to make it easier to parse.
+
+The only currently supported command is B<--version>.
+
+=item B<--no-pager>
+
+Disables the use of any pager when showing information (since dpkg 1.19.2).
+
+=item B<--no-debsig>
+
+Do not try to verify package signatures.
+
+=item B<--no-triggers>
+
+Do not run any triggers in this run (since dpkg 1.14.17), but activations
+will still be recorded.
+If used with B<--configure> I<package> or
+B<--triggers-only> I<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 B<triggers-awaited> and
+B<triggers-pending> states. This can be fixed later by running:
+B<dpkg --configure --pending>.
+
+=item B<--triggers>
+
+Cancels a previous B<--no-triggers> (since dpkg 1.14.17).
+
+=back
+
+=head1 EXIT STATUS
+
+=over
+
+=item B<0>
+
+The requested action was successfully performed.
+Or a check or assertion command returned true.
+
+=item B<1>
+
+A check or assertion command returned false.
+
+=item B<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.
+
+=back
+
+=head1 ENVIRONMENT
+
+=head2 External environment
+
+=over
+
+=item B<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, B<dpkg> will abort.
+
+=item B<HOME>
+
+If set, B<dpkg> will use it as the directory from which to read the user
+specific configuration file.
+
+=item B<TMPDIR>
+
+If set, B<dpkg> will use it as the directory in which to create
+temporary files and directories.
+
+=item B<SHELL>
+
+The program B<dpkg> will execute when starting a new interactive shell,
+or when spawning a command via a shell.
+
+=item B<PAGER>
+
+=item B<DPKG_PAGER>
+
+The program B<dpkg> will execute when running a pager,
+which will be executed with «B<$SHELL -c>»,
+for example when displaying the conffile differences.
+If B<SHELL> is not set, «B<sh>» will be used instead.
+The B<DPKG_PAGER> overrides the B<PAGER> environment variable
+(since dpkg 1.19.2).
+
+=item B<DPKG_COLORS>
+
+Sets the color mode (since dpkg 1.18.5).
+The currently accepted values are: B<auto> (default), B<always> and
+B<never>.
+
+=item B<DPKG_DEBUG>
+
+Sets the debug mask (since dpkg 1.21.10) from an octal value.
+The currently accepted flags are described in the B<--debug> option.
+
+=item B<DPKG_FORCE>
+
+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 disabled.
+
+=item B<DPKG_ADMINDIR>
+
+If set and the B<--admindir> or B<--root> options have not been
+specified, it will be used as the B<dpkg> administrative directory
+(since dpkg 1.20.0).
+
+=item B<DPKG_FRONTEND_LOCKED>
+
+Set by a package manager frontend to notify dpkg that it should not acquire
+the frontend lock (since dpkg 1.19.1).
+
+=back
+
+=head2 Internal environment
+
+=over
+
+=item B<LESS>
+
+Defined by B<dpkg> to “B<-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 B<PAGER> or B<DPKG_PAGER>
+variables can be set to disable specific options with «B<-+>», for
+example B<DPKG_PAGER="less -+F">.
+
+=item B<DPKG_ROOT>
+
+Defined by B<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 B<instdir>, B<dpkg>
+normally invokes maintainer scripts using B<chroot>(2) and leaves
+this variable empty, but if B<--force-script-chrootless> is
+specified then the B<chroot>(2) call is skipped and B<instdir>
+is non-empty.
+
+=item B<DPKG_ADMINDIR>
+
+Defined by B<dpkg> on the maintainer script environment to indicate
+the B<dpkg> administrative directory to use (since dpkg 1.16.0).
+This variable is always set to the current B<--admindir> value.
+
+=item B<DPKG_FORCE>
+
+Defined by B<dpkg> on the subprocesses environment to all the currently
+enabled force option names separated by commas (since dpkg 1.19.5).
+
+=item B<DPKG_SHELL_REASON>
+
+Defined by B<dpkg> on the shell spawned on the conffile prompt to
+examine the situation (since dpkg 1.15.6).
+Current valid value: B<conffile-prompt>.
+
+=item B<DPKG_CONFFILE_OLD>
+
+Defined by B<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.
+
+=item B<DPKG_CONFFILE_NEW>
+
+Defined by B<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.
+
+=item B<DPKG_HOOK_ACTION>
+
+Defined by B<dpkg> on the shell spawned when executing a hook action
+(since dpkg 1.15.4).
+Contains the current B<dpkg> action.
+
+=item B<DPKG_RUNNING_VERSION>
+
+Defined by B<dpkg> on the maintainer script environment to the
+version of the currently running B<dpkg> instance (since dpkg 1.14.17).
+
+=item B<DPKG_MAINTSCRIPT_PACKAGE>
+
+Defined by B<dpkg> on the maintainer script environment to the
+(non-arch-qualified) package name being handled (since dpkg 1.14.17).
+
+=item B<DPKG_MAINTSCRIPT_PACKAGE_REFCOUNT>
+
+Defined by B<dpkg> on the maintainer script environment to the
+package reference count, i.e. the number of package instances with
+a state greater than B<not-installed> (since dpkg 1.17.2).
+
+=item B<DPKG_MAINTSCRIPT_ARCH>
+
+Defined by B<dpkg> on the maintainer script environment to the
+architecture the package got built for (since dpkg 1.15.4).
+
+=item B<DPKG_MAINTSCRIPT_NAME>
+
+Defined by B<dpkg> on the maintainer script environment to the
+name of the script running, one of B<preinst>, B<postinst>,
+B<prerm> or B<postrm> (since dpkg 1.15.7).
+
+=item B<DPKG_MAINTSCRIPT_DEBUG>
+
+Defined by B<dpkg> on the maintainer script environment to a value
+(‘B<0>’ or ‘B<1>’) noting whether debugging has been
+requested (with the B<--debug> option) for the maintainer scripts
+(since dpkg 1.18.4).
+
+=back
+
+=head1 FILES
+
+=over
+
+=item I<%PKGCONFDIR%/dpkg.cfg.d/[0-9a-zA-Z_-]*>
+
+Configuration fragment files (since dpkg 1.15.4).
+
+=item I<%PKGCONFDIR%/dpkg.cfg>
+
+Configuration file with default options.
+
+=item I<%LOGDIR%/dpkg.log>
+
+Default log file (see I<%PKGCONFDIR%/dpkg.cfg> and option
+B<--log>).
+
+=back
+
+The other files listed below are in their default directories, see option
+B<--admindir> to see how to change locations of these files.
+
+=over
+
+=item I<%ADMINDIR%/available>
+
+List of available packages.
+
+=item I<%ADMINDIR%/status>
+
+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 B<INFORMATION ABOUT PACKAGES>
+for more info.
+
+The status file is backed up daily in I<%BACKUPSDIR%>. It can be
+useful if it's lost or corrupted due to filesystems troubles.
+
+=back
+
+The format and contents of a binary package are described in B<deb>(5).
+
+=head1 BUGS
+
+B<--no-act> usually gives less information than might be helpful.
+
+=head1 EXAMPLES
+
+To list installed packages related to the editor B<vi>(1) (note that
+B<dpkg-query> does not load the I<available> file anymore by
+default, and the B<dpkg-query> B<--load-avail> option should
+be used instead for that):
+
+=over
+
+ dpkg -l '*vi*'
+
+=back
+
+To see the entries in I<%ADMINDIR%/available> of two packages:
+
+=over
+
+ dpkg --print-avail elvis vim | less
+
+=back
+
+To search the listing of packages yourself:
+
+=over
+
+ less %ADMINDIR%/available
+
+=back
+
+To remove an installed elvis package:
+
+=over
+
+ dpkg -r elvis
+
+=back
+
+To install a package, you first need to find it in an archive or
+CDROM. The I<available> file shows that the vim package is in section
+B<editors>:
+
+=over
+
+ cd /media/cdrom/pool/main/v/vim
+ dpkg -i vim_4.5-3.deb
+
+=back
+
+To make a local copy of the package selection states:
+
+=over
+
+ dpkg --get-selections> myselections
+
+=back
+
+You might transfer this file to another computer, and after having updated
+the I<available> file there with your package manager frontend of choice
+(see L<https://wiki.debian.org/Teams/Dpkg/FAQ#set-selections> for more
+details), for example:
+
+=over
+
+ apt-cache dumpavail | dpkg --merge-avail
+
+=back
+
+or with dpkg 1.17.6 and earlier:
+
+=over
+
+ avail=$(mktemp)
+ apt-cache dumpavail> "$avail"
+ dpkg --merge-avail "$avail"
+ rm "$avail"
+
+=back
+
+you can install it with:
+
+=over
+
+ dpkg --clear-selections
+ dpkg --set-selections <myselections
+
+=back
+
+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 B<apt-get dselect-upgrade>.
+
+Ordinarily, you will find that B<dselect>(1) provides a more
+convenient way to modify the package selection states.
+
+=head1 ADDITIONAL FUNCTIONALITY
+
+Additional functionality can be gained by installing any of the
+following packages: B<apt>, B<aptitude> and B<debsums>.
+
+=head1 SEE ALSO
+
+B<aptitude>(8),
+B<apt>(8),
+B<dselect>(1),
+B<dpkg-deb>(1),
+B<dpkg-query>(1),
+B<deb>(5),
+B<deb-control>(5),
+B<dpkg.cfg>(5),
+and
+B<dpkg-reconfigure>(8).
+
+=head1 AUTHORS
+
+See I<%PKGDOCDIR%/THANKS> for the list of people who have
+contributed to B<dpkg>.