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 con-
       sidered the user's "back-end" to other tools using the APT library.

       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  per-
              formed  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  circum-
              stances  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.

              is used in conjunction with  the  traditional  Debian  GNU/Linux
              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  ver-
              sions  of  packages;  apt-get  has a "smart" conflict resolution
              system, and it will attempt to upgrade the most important  pack-
              ages  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.

              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 pack-
       age 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  distri-
       bution or the Archive name (stable, frozen, unstable).

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

       If no package matches the given expression and the expression  contains
       one of '.', '?' or '*' then it is assumed to be a POSIX regex 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 prefix  with
       a '^' character.

       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

       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 mech-
       anism 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 packages.

       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
              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 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 soltion.  Any  Package
              that  are  specified  must  completly  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 elimi-
              nate  some  of  the  offending  packages).  Use  of  this option
              together with -m may produce an error in some situations.   Con-
              figuration 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





              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 (rare).



              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-



              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:

              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.   Configura-
              tion Item: APT::Get::Print-URIs.

              Use  purge instead of remove for anything that would be removed.
              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:

              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.  Con-
              figuration 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  ta-
              ble.  Configuration Item: APT::Get::Only-Source


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

              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 arbitary configura-
              tion 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 Configuration  Item:  Dir::Etc::Prefer-

              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),  The  APT User's guide in /usr/share/doc/apt/, apt_prefer-


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

                                17 August 2003                      apt-get(8)