Provided by: apt_0.8.16~exp12ubuntu10_amd64 bug

NAME

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

SYNOPSIS

       apt-get [-sqdyfmubV] [-o= config_string ] [-c= config_file ] [-t= target_release]
               [-a= default_architecture] {update | upgrade | dselect-upgrade | dist-upgrade |
               install pkg [ { =pkg_version_number | /target_release } ] ...  | remove pkg...  |
               purge pkg...  | source pkg [ { =pkg_version_number | /target_release } ] ...  |
               build-dep pkg...  | check | clean | autoclean | autoremove | {-v | --version} |
               {-h | --help}}

DESCRIPTION

       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(1), aptitude(8), synaptic(8) and wajig(1).

       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
           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 available.

       dselect-upgrade
           dselect-upgrade is used in conjunction with the traditional Debian packaging
           front-end, dselect(1).  dselect-upgrade follows the changes made by dselect(1) 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
           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. So, dist-upgrade command may
           remove some packages. 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
           install is followed by one or more packages desired for installation or upgrading.
           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.

           This is also the target to use if you want to upgrade one or more already-installed
           packages without upgrading every package you have on your system. Unlike the "upgrade"
           target, which installs the newest version of all currently installed packages,
           "install" will install the newest version of only the package(s) specified. Simply
           provide the name of the package(s) you wish to upgrade, and if a newer version is
           available, it (and its dependencies, as described above) will be downloaded and
           installed.

           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.
           Note the removing a package leaves its configuration files in system. If a plus sign
           is appended to the package name (with no intervening space), the identified package
           will be installed instead of removed.

       purge
           purge is identical to remove except that packages are removed and purged (any
           configuration files are deleted too).

       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 while
           respect the default release, set with the option APT::Default-Release, the -t option
           or per package with the pkg/release syntax, if possible.

           Source packages are tracked separately from binary packages via deb-src type lines in
           the sources.list(5) file. This means that you will need to add such a line for each
           repository you want to get sources from. If you don't do this you will properly get
           another (newer, older or none) source version than the one you have installed or could
           install.

           If the --compile option is specified then the package will be compiled to a binary
           .deb using dpkg-buildpackage for the architecture as defined by the
           --host-architecture option. 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
           build-dep causes apt-get to install/remove packages in an attempt to satisfy the build
           dependencies for a source package. By default the dependencies are satisfied to build
           the package natively. If desired a host-architecture can be specified with the
           --host-architecture option instead.

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

       download
           download will download the given binary package into the current directory.

       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(1) 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.

       autoclean
           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.

       autoremove
           autoremove is used to remove packages that were automatically installed to satisfy
           dependencies for other packages and are now no longer needed.

       changelog
           changelog downloads a package changelog and displays it through sensible-pager. The
           server name and base directory is defined in the APT::Changelogs::Server variable (e.
           g.  http://packages.debian.org/changelogs for Debian or
           http://changelogs.ubuntu.com/changelogs for Ubuntu). By default it displays the
           changelog for the version that is installed. However, you can specify the same options
           as for the install command.

OPTIONS

       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.

       --no-install-recommends
           Do not consider recommended packages as a dependency for installing. Configuration
           Item: APT::Install-Recommends.

       --install-suggests
           Consider suggested packages as a dependency for installing. Configuration Item:
           APT::Install-Suggests.

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

       -f, --fix-broken
           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. If packages are specified, these have to 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(1) 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.

       -m, --ignore-missing, --fix-missing
           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: APT::Get::Fix-Missing.

       --no-download
           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.

       -q, --quiet
           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.

       -s, --simulate, --just-print, --dry-run, --recon, --no-act
           No action; perform a simulation of events that would occur but do not actually change
           the system. Configuration Item: APT::Get::Simulate.

           Simulation run as user will deactivate locking (Debug::NoLocking) automatic. Also a
           notice will be displayed indicating that this is only a simulation, if the option
           APT::Get::Show-User-Simulation-Note is set (Default: true). Neither NoLocking nor the
           notice will be triggered if run as root (root should know what he is doing without
           further warnings by apt-get).

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

       -y, --yes, --assume-yes
           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,
           trying to install a unauthenticated package or removing an essential package occurs
           then apt-get will abort. Configuration Item: APT::Get::Assume-Yes.

       --assume-no
           Automatic "no" to all prompts. Configuration Item: APT::Get::Assume-No.

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

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

       -a, --host-architecture
           This option controls the architecture packages are built for by apt-get source
           --compile and how cross-builddependencies are satisfied. By default is it not set
           which means that the host architecture is the same as the build architecture (which is
           defined by APT::Architecture). Configuration Item: APT::Get::Host-Architecture

       -b, --compile, --build
           Compile source packages after downloading them. Configuration Item: APT::Get::Compile.

       --ignore-hold
           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.

       --no-upgrade
           Do not upgrade packages; When used in conjunction with install, no-upgrade will
           prevent packages on the command line from being upgraded if they are already
           installed. Configuration Item: APT::Get::Upgrade.

       --only-upgrade
           Do not install new packages; When used in conjunction with install, only-upgrade will
           prevent packages on the command line from being upgraded if they are not already
           installed. Configuration Item: APT::Get::Only-Upgrade.

       --force-yes
           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.

       --print-uris
           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.

       --purge
           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.  remove --purge is
           equivalent to the purge command. Configuration Item: APT::Get::Purge.

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

       --list-cleanup
           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.

       -t, --target-release, --default-release
           This option controls the default input to the policy engine, it creates a default pin
           at priority 990 using the specified release string. This overrides the general
           settings in /etc/apt/preferences. Specifically pinned packages are not affected by the
           value of this option. 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*',
           -t unstable or -t sid. Configuration Item: APT::Default-Release; see also the
           apt_preferences(5) manual page.

       --trivial-only
           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.

       --no-remove
           If any packages are to be removed apt-get immediately aborts without prompting.
           Configuration Item: APT::Get::Remove.

       --auto-remove
           If the command is either install or remove, then this option acts like running
           autoremove command, removing the unused dependency packages. Configuration Item:
           APT::Get::AutomaticRemove.

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

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

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

       --allow-unauthenticated
           Ignore if packages can't be authenticated and don't prompt about it. This is useful
           for tools like pbuilder. Configuration Item: APT::Get::AllowUnauthenticated.

       -h, --help
           Show a short usage summary.

       -v, --version
           Show the program version.

       -c, --config-file
           Configuration File; Specify a configuration file to use. The program will read the
           default configuration file and then this configuration file. If configuration settings
           need to be set before the default configuration files are parsed specify a file with
           the APT_CONFIG environment variable. See apt.conf(5) for syntax information.

       -o, --option
           Set a Configuration Option; This will set an arbitrary configuration option. The
           syntax is -o Foo::Bar=bar.  -o and --option can be used multiple times to set
           different options.

FILES

       /etc/apt/sources.list
           Locations to fetch packages from. Configuration Item: Dir::Etc::SourceList.

       /etc/apt/sources.list.d/
           File fragments for locations to fetch packages from. Configuration Item:
           Dir::Etc::SourceParts.

       /etc/apt/apt.conf
           APT configuration file. Configuration Item: Dir::Etc::Main.

       /etc/apt/apt.conf.d/
           APT configuration file fragments. Configuration Item: Dir::Etc::Parts.

       /etc/apt/preferences
           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.

       /etc/apt/preferences.d/
           File fragments for the version preferences. Configuration Item:
           Dir::Etc::PreferencesParts.

       /var/cache/apt/archives/
           Storage area for retrieved package files. Configuration Item: Dir::Cache::Archives.

       /var/cache/apt/archives/partial/
           Storage area for package files in transit. Configuration Item: Dir::Cache::Archives
           (implicit partial).

       /var/lib/apt/lists/
           Storage area for state information for each package resource specified in
           sources.list(5) Configuration Item: Dir::State::Lists.

       /var/lib/apt/lists/partial/
           Storage area for state information in transit. Configuration Item: Dir::State::Lists
           (implicit partial).

SEE ALSO

       apt-cache(8), apt-cdrom(8), dpkg(1), dselect(1), sources.list(5), apt.conf(5), apt-
       config(8), apt-secure(8), The APT User's guide in /usr/share/doc/apt-doc/,
       apt_preferences(5), the APT Howto.

DIAGNOSTICS

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

ORIGINAL AUTHORS

       Jason Gunthorpe

CURRENT AUTHORS

       APT team

       QA Page[3]

BUGS

       APT bug page[4]. If you wish to report a bug in APT, please see
       /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.

AUTHORS

       Jason Gunthorpe

       APT team

NOTES

        1. http://packages.debian.org/changelogs

        2. http://changelogs.ubuntu.com/changelogs

        3. QA Page
           http://packages.qa.debian.org/a/apt.html

        4. APT bug page
           http://bugs.debian.org/src:apt