APT-GET(8)                                                          APT-GET(8)

       apt-get - APT package handling utility -- command-line interface

       apt-get [ -hvs ] [ -o=config string ] [ -c=file ] { update | upgrade |
       dselect-upgrade | install  pkg ... | remove  pkg ... | source  pkg ...
       | build-dep  pkg ... | check | clean | autoclean }

       apt-get is the command-line tool for handling packages, and may be
       considered the user's "back-end" to other tools using the APT library.
       Several "front-end" interfaces exist, such as dselect(8), aptitude,
       synaptic, gnome-apt and wajig.

       Unless the -h, or --help option is given, one of the commands below
       must be present.

       update update is used to resynchronize the package index files from
              their sources. The indexes of available packages are fetched
              from the location(s) specified in /etc/apt/sources.list.  For
              example, when using a Debian archive, this command retrieves and
              scans the Packages.gz files, so that information about new and
              updated packages is available. An update should always be
              performed before an upgrade or dist-upgrade. Please be aware
              that the overall progress meter will be incorrect as the size of
              the package files cannot be known in advance.

              upgrade is used to install the newest versions of all packages
              currently installed on the system from the sources enumerated in
              /etc/apt/sources.list. Packages currently installed with new
              versions available are retrieved and upgraded; under no
              circumstances are currently installed packages removed, or
              packages not already installed retrieved and installed. New
              versions of currently installed packages that cannot be upgraded
              without changing the install status of another package will be
              left at their current version. An update must be performed first
              so that apt-get knows that new versions of packages are

              dselect-upgrade is used in conjunction with the traditional
              Debian packaging front-end, dselect(8). dselect-upgrade follows
              the changes made by dselect(8) to the Status field of available
              packages, and performs the actions necessary to realize that
              state (for instance, the removal of old and the installation of
              new packages).

              dist-upgrade, in addition to performing the function of upgrade,
              also intelligently handles changing dependencies with new
              versions of packages; apt-get has a "smart" conflict resolution
              system, and it will attempt to upgrade the most important
              packages at the expense of less important ones if necessary.
              The /etc/apt/sources.list file contains a list of locations from
              which to retrieve desired package files.  See also
              apt_preferences(5) for a mechanism for overriding the general
              settings for individual packages.

              install is followed by one or more packages desired for
              installation. Each package is a package name, not a fully
              qualified filename (for instance, in a Debian GNU/Linux system,
              libc6 would be the argument provided, not libc6_1.9.6-2.deb).
              All packages required by the package(s) specified for
              installation will also be retrieved and installed. The
              /etc/apt/sources.list file is used to locate the desired
              packages. If a hyphen is appended to the package name (with no
              intervening space), the identified package will be removed if it
              is installed. Similarly a plus sign can be used to designate a
              package to install. These latter features may be used to
              override decisions made by apt-get's conflict resolution system.

              A specific version of a package can be selected for installation
              by following the package name with an equals and the version of
              the package to select. This will cause that version to be
              located and selected for install. Alternatively a specific
              distribution can be selected by following the package name with
              a slash and the version of the distribution or the Archive name
              (stable, testing, unstable).

              Both of the version selection mechanisms can downgrade packages
              and must be used with care.

              Finally, the apt_preferences(5) mechanism allows you to create
              an alternative installation policy for individual packages.

              If no package matches the given expression and the expression
              contains one of '.', '?' or '*' then it is assumed to be a POSIX
              regular expression, and it is applied to all package names in
              the database. Any matches are then installed (or removed). Note
              that matching is done by substring so 'lo.*' matches 'how-lo'
              and 'lowest'. If this is undesired, anchor the regular
              expression with a '^' or '$' character, or create a more
              specific regular expression.

       remove remove is identical to install except that packages are removed
              instead of installed. If a plus sign is appended to the package
              name (with no intervening space), the identified package will be
              installed instead of removed.

       source source causes apt-get to fetch source packages. APT will examine
              the available packages to decide which source package to fetch.
              It will then find and download into the current directory the
              newest available version of that source package. Source packages
              are tracked separately from binary packages via deb-src type
              lines in the sources.list(5) file. This probably will mean that
              you will not get the same source as the package you have
              installed or as you could install. If the --compile options is
              specified then the package will be compiled to a binary .deb
              using dpkg-buildpackage, if --download-only is specified then
              the source package will not be unpacked.

              A specific source version can be retrieved by postfixing the
              source name with an equals and then the version to fetch,
              similar to the mechanism used for the package files. This
              enables exact matching of the source package name and version,
              implicitly enabling the APT::Get::Only-Source option.

              Note that source packages are not tracked like binary packages,
              they exist only in the current directory and are similar to
              downloading source tar balls.

              build-dep causes apt-get to install/remove packages in an
              attempt to satisfy the build dependencies for a source package.

       check  check is a diagnostic tool; it updates the package cache and
              checks for broken dependencies.

       clean  clean clears out the local repository of retrieved package
              files. It removes everything but the lock file from
              /var/cache/apt/archives/ and /var/cache/apt/archives/partial/.
              When APT is used as a dselect(8) method, clean is run
              automatically.  Those who do not use dselect will likely want to
              run apt-get clean from time to time to free up disk space.

              Like clean, autoclean clears out the local repository of
              retrieved package files. The difference is that it only removes
              package files that can no longer be downloaded, and are largely
              useless. This allows a cache to be maintained over a long period
              without it growing out of control. The configuration option
              APT::Clean-Installed will prevent installed packages from being
              erased if it is set to off.

       All command line options may be set using the configuration file, the
       descriptions indicate the configuration option to set. For boolean
       options you can override the config file by using something like
       -f-,--no-f, -f=no or several other variations.


              Download only; package files are only retrieved, not unpacked or
              installed.  Configuration Item: APT::Get::Download-Only.


              Fix; attempt to correct a system with broken dependencies in
              place. This option, when used with install/remove, can omit any
              packages to permit APT to deduce a likely solution. Any Package
              that are specified must completely correct the problem. The
              option is sometimes necessary when running APT for the first
              time; APT itself does not allow broken package dependencies to
              exist on a system. It is possible that a system's dependency
              structure can be so corrupt as to require manual intervention
              (which usually means using dselect(8) or dpkg --remove to
              eliminate some of the offending packages). Use of this option
              together with -m may produce an error in some situations.
              Configuration Item: APT::Get::Fix-Broken.



              Ignore missing packages; If packages cannot be retrieved or fail
              the integrity check after retrieval (corrupted package files),
              hold back those packages and handle the result. Use of this
              option together with -f may produce an error in some situations.
              If a package is selected for installation (particularly if it is
              mentioned on the command line) and it could not be downloaded
              then it will be silently held back.  Configuration Item:

              Disables downloading of packages. This is best used with
              --ignore-missing to force APT to use only the .debs it has
              already downloaded.  Configuration Item: APT::Get::Download.


              Quiet; produces output suitable for logging, omitting progress
              indicators.  More q's will produce more quiet up to a maximum of
              2. You can also use -q=# to set the quiet level, overriding the
              configuration file.  Note that quiet level 2 implies -y, you
              should never use -qq without a no-action modifier such as -d,
              --print-uris or -s as APT may decided to do something you did
              not expect.  Configuration Item: quiet.






              No action; perform a simulation of events that would occur but
              do not actually change the system.  Configuration Item:

              Simulate prints out a series of lines each one representing a
              dpkg operation, Configure (Conf), Remove (Remv), Unpack (Inst).
              Square brackets indicate broken packages with and empty set of
              square brackets meaning breaks that are of no consequence



              Automatic yes to prompts; assume "yes" as answer to all prompts
              and run non-interactively. If an undesirable situation, such as
              changing a held package or removing an essential package occurs
              then apt-get will abort.  Configuration Item: APT::Get::Assume-


              Show upgraded packages; Print out a list of all packages that
              are to be upgraded.  Configuration Item: APT::Get::Show-


              Show full versions for upgraded and installed packages.
              Configuration Item: APT::Get::Show-Versions.



              Compile source packages after downloading them.  Configuration
              Item: APT::Get::Compile.

              Ignore package Holds; This causes apt-get to ignore a hold
              placed on a package. This may be useful in conjunction with
              dist-upgrade to override a large number of undesired holds.
              Configuration Item: APT::Ignore-Hold.

              Do not upgrade packages; When used in conjunction with install
              no-upgrade will prevent packages listed from being upgraded if
              they are already installed.  Configuration Item:

              Force yes; This is a dangerous option that will cause apt to
              continue without prompting if it is doing something potentially
              harmful. It should not be used except in very special
              situations. Using force-yes can potentially destroy your system!
              Configuration Item: APT::Get::force-yes.

              Instead of fetching the files to install their URIs are printed.
              Each URI will have the path, the destination file name, the size
              and the expected md5 hash. Note that the file name to write to
              will not always match the file name on the remote site! This
              also works with the source and update commands. When used with
              the update command the MD5 and size are not included, and it is
              up to the user to decompress any compressed files.
              Configuration Item: APT::Get::Print-URIs.

              Use purge instead of remove for anything that would be removed.
              An asterisk ("*") will be displayed next to packages which are
              scheduled to be purged.  Configuration Item: APT::Get::Purge.

              Re-Install packages that are already installed and at the newest
              version.  Configuration Item: APT::Get::ReInstall.

              This option defaults to on, use --no-list-cleanup to turn it
              off. When on apt-get will automatically manage the contents of
              /var/lib/apt/lists to ensure that obsolete files are erased.
              The only  reason to turn it off is if you frequently change your
              source list.  Configuration Item: APT::Get::List-Cleanup.



              This option controls the default input to the policy engine, it
              creates a default pin at priority 990 using the specified
              release string. The preferences file may further override this
              setting. In short, this option lets you have simple control over
              which distribution packages will be retrieved from. Some common
              examples might be -t '2.1*' or -t unstable.  Configuration Item:
              APT::Default-Release; see also the apt_preferences(5) manual

              Only perform operations that are 'trivial'. Logically this can
              be considered related to --assume-yes, where --assume-yes will
              answer yes to any prompt, --trivial-only will answer no.
              Configuration Item: APT::Get::Trivial-Only.

              If any packages are to be removed apt-get immediately aborts
              without prompting.  Configuration Item: APT::Get::Remove

              Only has meaning for the source command.  Indicates that the
              given source names are not to be mapped through the binary
              table.  This means that if this option is specified, the source
              command will only accept source package names as arguments,
              rather than accepting binary package names and looking up the
              corresponding source package.  Configuration Item:


              Download only the diff or tar file of a source archive.
              Configuration Item: APT::Get::Diff-Only and APT::Get::Tar-Only

              Only process architecture-dependent build-dependencies.
              Configuration Item: APT::Get::Arch-Only


       --help Show a short usage summary.


              Show the program version.


              Configuration File; Specify a configuration file to use.  The
              program will read the default configuration file and then this
              configuration file. See apt.conf(5) for syntax information.


              Set a Configuration Option; This will set an arbitrary
              configuration option. The syntax is -o Foo::Bar=bar.

              Locations to fetch packages from.  Configuration Item:

              APT configuration file.  Configuration Item: Dir::Etc::Main.

              APT configuration file fragments Configuration Item:

              Version preferences file.  This is where you would specify
              "pinning", i.e. a preference to get certain packages from a
              separate source or from a different version of a distribution.
              Configuration Item: Dir::Etc::Preferences.

              Storage area for retrieved package files.  Configuration Item:

              Storage area for package files in transit.  Configuration Item:
              Dir::Cache::Archives (implicit partial).

              Storage area for state information for each package resource
              specified in sources.list(5) Configuration Item:

              Storage area for state information in transit.  Configuration
              Item: Dir::State::Lists (implicit partial).

       apt-cache(8), apt-cdrom(8), dpkg(8), dselect(8), sources.list(5),
       apt.conf(5), apt-config(8), The APT User's guide in
       /usr/share/doc/apt/, apt_preferences(5), the APT Howto.

       apt-get returns zero on normal operation, decimal 100 on error.

       See the APT bug page <URL:http://bugs.debian.org/src:apt>.  If you wish
       to report a bug in APT, please see /usr/share/doc/debian/bug-
       reporting.txt or the reportbug(1) command.

       APT was written by the APT team <apt@packages.debian.org>.

                                16 October 2007                     APT-GET(8)