Provided by:
dpkg_1.14.5ubuntu16_i386 
NAME
dpkg - package manager for Debian
SYNOPSIS
dpkg [options] action
WARNING
This manual is intended for users wishing to understand dpkg’s command
line options and package states in more detail than that provided by
dpkg --help.
It should not be used by package maintainers wishing to understand how
dpkg will install their packages. The descriptions of what dpkg does
when installing and removing packages are particularly inadequate.
DESCRIPTION
dpkg is a tool to install, build, remove and manage Debian packages.
The primary and more user-friendly front-end for dpkg is dselect(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 be also be used as a front-end to dpkg-deb(1). The following
are dpkg-deb actions, and if they are encountered, dpkg just runs
dpkg-deb with the parameters given to it:
-b, --build,
-c, --contents,
-I, --info,
-f, --field,
-e, --control,
-x, --extract,
-X, --vextract, and
--fsys-tarfile.
Please refer to dpkg-deb(1) for information about these actions.
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
installed
The package is unpacked and configured OK.
half-installed
The installation of the package has been started, but not com‐
pleted for some reason.
not-installed
The package is not installed on your system.
unpacked
The package is unpacked, but not configured.
half-configured
The package is unpacked and configuration has been started, but
not yet completed for some reason.
config-files
Only the configuration files of the package exist on the system.
PACKAGE SELECTION STATES
install
The package is selected for installation.
deinstall
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, even configuration files).
PACKAGE FLAGS
hold A package marked to be on hold is not handled by dpkg, unless
forced to do that with option --force-hold.
reinst-required
A package marked reinst-required is broken and requires rein‐
stallation. These packages cannot be removed, unless forced with
option --force-remove-reinstreq.
ACTIONS
dpkg -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 pack‐
age. 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 informa‐
tion about how this is done.
dpkg --unpack package_file ...
Unpack the package, but don’t configure it. If --recursive or -R
option is specified, package_file must refer to a directory
instead.
dpkg --configure package ... | -a | --pending
Reconfigure an unpacked package. If -a or --pending is given
instead of package, all unpacked but unconfigured packages are
configured.
Configuring consists of the following steps:
1. Unpack the configuration files, and at the same time back up
the old configuration files, so that they can be restored if
something goes wrong.
2. Run postinst script, if provided by the package.
dpkg -r | --remove | -P | --purge package ... | -a | --pending
Remove an installed package. -r or --remove remove everything
except configuration files. This may avoid having to reconfigure
the package if it is reinstalled later. (Configuration files are
the files listed in the debian/conffiles control file). -P or
--purge removes everything, including configuration files. If -a
or --pending is given instead of a package name, then all pack‐
ages unpacked, but marked to be removed or purged in file
/var/lib/dpkg/status, are removed or purged, respectively.
Removing of a package consists of the following steps:
1. Run prerm script
2. Remove the installed files
3. Run postrm script
dpkg --update-avail | --merge-avail Packages-file
Update dpkg’s and dselect’s idea of which packages are avail‐
able. 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 Pack‐
ages-file. The Packages-file distributed with Debian is simply
named Packages. dpkg keeps its record of available packages in
/var/lib/dpkg/available.
A simpler one-shot command to retrieve and update the available
file is dselect update.
dpkg -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 direc‐
tory instead.
dpkg --forget-old-unavail
Forget about uninstalled unavailable packages.
dpkg --clear-avail
Erase the existing information about what packages are avail‐
able.
dpkg -C | --audit
Searches for packages that have been installed only partially on
your system. dpkg will suggest what to do with them to get them
working.
dpkg --get-selections [package-name-pattern...]
Get list of package selections, and write it to stdout. Without
a pattern, packages marked with state purge will not be shown.
dpkg --set-selections
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.
dpkg --clear-selections
Set the requested state of every non-essential package to dein‐
stall. This is intended to be used immediately before
--set-selections, to deinstall any packages not in list given to
--set-selections.
dpkg --yet-to-unpack
Searches for packages selected for installation, but which for
some reason still haven’t been installed.
dpkg --print-architecture
Print architecture of packages dpkg installs (for
example, "i386").
dpkg --compare-versions ver1 op ver2
Compare version numbers, where op is a binary operator.
dpkg returns success (zero result) if the specified con‐
dition is satisfied, and failure (nonzero result) other‐
wise. 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 ver‐
sion: lt-nl le-nl ge-nl gt-nl. These are provided only
for compatibility with control file syntax: < << <= = >=
>> >.
dpkg --command-fd <n>
Accept a series of commands on input file descriptor <n>.
Note: additional options set on the command line, and
thru this file descriptor, are not reset for subsequent
commands executed during the same run.
dpkg --help
Display a brief help message.
dpkg --force-help
Give help about the --force-thing options.
dpkg -Dh | --debug=help
Give help about debugging options.
dpkg --licence | dpkg --license
Display dpkg licence.
dpkg --version
Display dpkg version information.
dpkg-deb actions
See dpkg-deb(1) for more information about the following
actions.
dpkg -b | --build directory [filename]
Build a deb package.
dpkg -c | --contents filename
List contents of a deb package.
dpkg -e | --control filename [directory]
Extract control-information from a package.
dpkg -x | --extract filename directory
Extract the files contained by package.
dpkg -f | --field filename [control-field] ...
Display control field(s) of a package.
dpkg --fsys-tarfile filename
Display the filesystem tar-file contained by a
Debian package.
dpkg -I | --info filename [control-file]
Show information about a package.
dpkg -X | --vextract filename directory
Extract and display the filenames contained by a
package.
dpkg-query actions
See dpkg-query(1) for more information about the follow‐
ing actions.
dpkg -l | --list package-name-pattern ...
List packages matching given pattern.
dpkg -s | --status package-name ...
Report status of specified package.
dpkg -L | --listfiles package ...
List files installed to your system from package.
dpkg -S | --search filename-search-pattern ...
Search for a filename from installed packages.
dpkg -p | --print-avail package
Display details about package, as found in /var/lib/dpkg/available.
OPTIONS
All options can be specified both on the command line and in the
dpkg configuration file /etc/dpkg/dpkg.cfg. Each line in the
configuration file is either an option (exactly the same as the
command line option but without leading dashes) or a comment (if
it starts with a #).
--abort-after=number
Change after how many errors dpkg will abort. The default
is 50.
-B|--auto-deconfigure
When a package is removed, there is a possibility that
another installed package depended on the removed pack‐
age. Specifying this option will cause automatic decon‐
figuration of the package which depended on the removed
package.
-Doctal | --debug=octal
Switch debugging on. octal is formed by bitwise-orring
desired values together from the list below (note that
these values may change in future releases). -Dh or
--debug=help display these debugging values.
number description
1 Generally helpful progress information
2 Invocation and status of maintainer scripts
10 Output for each file processed
100 Lots of output for each file processed
20 Output for each configuration file
200 Lots of output for each configuration file
40 Dependencies and conflicts
400 Lots of dependencies/conflicts output
1000 Lots of drivel about e.g. the dpkg/info dir
2000 Insane amounts of drivel
--force-things | --no-force-things | --refuse-things
Force or refuse (no-force and refuse mean the same thing)
to do some things. things is a comma separated list of
things specified below. --force-help displays a message
describing them. Things marked with (*) are forced by
default.
Warning: These options are mostly intended to be used by
experts only. Using them without fully understanding
their effects may break your whole system.
all: Turns on (or off) all force options.
downgrade(*): Install a package, even if newer version of
it is already installed.
Warning: At present dpkg does not do any dependency
checking on downgrades and therefore will not warn you if
the downgrade breaks the dependency of some other pack‐
age. This can have serious side effects, downgrading
essential system components can even make your whole sys‐
tem 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 exam‐
ple, 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 consid‐
ered essential. Essential packages contain mostly very
basic Unix commands. Removing them might cause the whole
system to stop working, so use with caution.
depends: Turn all dependency problems into warnings.
depends-version: Don’t care about versions when checking
dependencies.
breaks: Install, even if this would break another pack‐
age.
conflicts: Install, even if it conflicts with another
package. This is dangerous, for it will usually cause
overwriting of some files.
confmiss: Always install a missing configuration file.
This is dangerous, since it means not preserving a change
(removing) made to the file.
confnew: If a conffile has been modified always install
the new version without prompting, unless the
--force-confdef is also specified, in which case the
default action is preferred.
confold: If a conffile has been modified always keep the
old version without prompting, unless the --force-confdef
is also specified, in which case the default action is
preferred.
confdef: If a conffile has been modified always choose
the default action. If there is no default action it will
stop to ask the user unless --force-confnew or
--force-confold is also been given, in which case it will
use that to decide the final action.
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.
architecture: Process even packages with the wrong archi‐
tecture.
bad-path: PATH is missing important programs, so problems
are likely.
not-root: Try to (de)install things even when not root.
bad-verify: Install a package even if it fails authentic‐
ity check.
--ignore-depends=package,...
Ignore dependency-checking for specified packages (actu‐
ally, checking is performed, but only warnings about con‐
flicts are given, nothing else).
--new | --old
Select new or old binary package format. This is a
dpkg-deb(1) option.
--nocheck
Don’t read or check contents of control file while build‐
ing a package. This is a dpkg-deb(1) option.
--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 prob‐
ably expected it to actually do nothing)
-R | --recursive
Recursively handle all regular files matching pattern
*.deb found at specified directories and all of its sub‐
directories. This can be used with -i, -A, --install,
--unpack and --avail actions.
-G Don’t install a package if a newer version of the same
package is already installed. This is an alias of
--refuse-downgrade.
--root=dir | --admindir=dir | --instdir=dir
Change default directories. admindir defaults to
/var/lib/dpkg and contains many files that give informa‐
tion about status of installed or uninstalled packages,
etc. instdir defaults to / and 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. Changing root changes inst
dir to dir and admindir to dir/var/lib/dpkg.
-O | --selected-only
Only process the packages that are selected for installa‐
tion. 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.
--status-fd n
Send machine-readable package status and progress infor‐
mation to file descriptor n. This option can be speci‐
fied multiple times. The information is generally one
record per line, in one of the following forms:
status: package: status
Package status changed; status is as in the status
file.
status: package : error : extended-error-message
An error occurred. Unfortunately at the time of
writing extended-error-message can contain
newlines, although in locales where the transla‐
tors have not made mistakes every newline is fol‐
lowed by at least one space.
status: file : conffile-prompt : real-old real-new
useredited distedited
User is being asked a configuration file question.
processing: stage: package
Sent just before a processing stage starts. stage
is one of upgrade, install (both sent before
unpacking), configure, trigproc, remove, purge.
--log=filename
Log status change updates and actions to filename,
instead of the default /var/log/dpkg.log. If this option
is given multiple times, the last filename is used. Log
messages are of the form ‘YYYY-MM-DD HH:MM:SS status
<state> <pkg> <installed-version>’ for status change
updates; ‘YYYY-MM-DD HH:MM:SS <action> <pkg> <installed-
version> <available-version>’ for actions where <action>
is one of install, upgrade, remove, purge; and ‘YYYY-MM-
DD HH:MM:SS conffile <filename> <decision>’ for conffile
changes where <decision> is either install or keep.
--no-debsig
Do not try to verify package signatures.
FILES
/etc/dpkg/dpkg.cfg
Configuration file with default options.
/var/log/dpkg.log
Default log file (see /etc/dpkg/dpkg.cfg(5) and option
--log).
The other files listed below are in their default directories,
see option --admindir to see how to change locations of these
files.
/var/lib/dpkg/available
List of available packages.
/var/lib/dpkg/status
Statuses of available packages. This file contains infor‐
mation 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 following files are components of a binary package. See
deb(5) for more information about them:
control
conffiles
preinst
postinst
prerm
postrm
DPKG_NO_TSTP
Define this to something if you prefer dpkg starting a
new shell rather than suspending itself, while doing a
shell escape.
SHELL The program dpkg will execute when starting a new shell.
COLUMNS
Sets the number of columns dpkg should use when display‐
ing formatted text. Currently only used by -l.
EXAMPLES
To list packages related to the editor vi(1):
dpkg -l '*vi*'
To see the entries in /var/lib/dpkg/available of two packages:
dpkg --print-avail elvis vim | less
To search the listing of packages yourself:
less /var/lib/dpkg/available
To remove an installed elvis package:
dpkg -r elvis
To install a package, you first need to find it in an archive or
CDROM. The "available" file shows that the vim package is in
section "editors":
cd /cdrom/hamm/hamm/binary/editors
dpkg -i vim_4.5-3.deb
To make a local copy of the package selection states:
dpkg --get-selections >myselections
You might transfer this file to another computer, and install it
there with:
dpkg --clear-selections
dpkg --set-selections <myselections
Note that this will not actually install or remove anything, but
just set the selection state on the requested packages. You will
need some other application to actually download and install the
requested packages. For example, run dselect and choose
"Install".
Ordinarily, you will find that dselect(1) provides a more conve‐
nient way to modify the package selection states.
Additional functionality can be gained by installing any of the
following packages: apt, aptitude and debsums.
dselect(1), dpkg-deb(1), dpkg-query(1), deb(5), deb-control(5),
dpkg.cfg(5), and dpkg-reconfigure(8).
BUGS
--no-act usually gives less information than might be helpful.
AUTHORS
See /usr/share/doc/dpkg/THANKS for the list of people who have
contributed to dpkg.