Provided by:
apt_0.6.43.3ubuntu2_i386 
NAME
apt-get - APT package handling utility -- command-line interface
SYNOPSIS
apt-get [-hvs] [-o=config string] [-c=file] {update | upgrade |
dselect-upgrade | install pkg... | remove pkg... |
source pkg... | build-dep pkg... | check | clean | autoclean}
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(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
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(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
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
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
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.
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.
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.
-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. 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.
-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.
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
(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.
-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.
-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.
--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. 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. 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 â€â€™2.1*â€â€™ or -t unstable. 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.
--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, --tar-only
Download only the diff or tar file of a source archive.
Configuration Item: APT::Get::Diff-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 usefull 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. See apt.conf(5) for syntax information.
-o, --option
Set a Configuration Option; This will set an arbitary
configuration option. The syntax is -o Foo::Bar=bar.
FILES
/etc/apt/sources.list
Locations to fetch packages from. Configuration Item:
Dir::Etc::SourceList.
/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.
/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(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.
DIAGNOSTICS
apt-get returns zero on normal operation, decimal 100 on error.
BUGS
APT bug page: 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.
AUTHORS
Jason Gunthorpe, APT team.