Provided by: apt_0.7.9ubuntu17_i386 bug

NAME

       apt-cache - APT package handling utility -- cache manipulator

SYNOPSIS

       apt-cache [-hvsn] [-o=config string] [-c=file] {[add file...] |
                 [gencaches] | [showpkg pkg...] | [showsrc pkg...] | [stats] |
                 [dump] | [dumpavail] | [unmet] | [search regex] |
                 [show pkg...] | [depends pkg...] | [rdepends pkg...] |
                 [pkgnames prefix] | [dotty pkg...] | [policy pkgs...] |
                 [madison pkgs...]}

DESCRIPTION

       apt-cache performs a variety of operations on APT´s package cache.
       apt-cache does not manipulate the state of the system but does provide
       operations to search and generate interesting output from the package
       metadata.

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

       add file(s)
           add adds the named package index files to the package cache. This
           is for debugging only.

       gencaches
           gencaches performs the same operation as apt-get check. It builds
           the source and package caches from the sources in sources.list(5)
           and from /var/lib/dpkg/status.

       showpkg pkg(s)
           showpkg displays information about the packages listed on the
           command line. Remaining arguments are package names. The available
           versions and reverse dependencies of each package listed are
           listed, as well as forward dependencies for each version. Forward
           (normal) dependencies are those packages upon which the package in
           question depends; reverse dependencies are those packages that
           depend upon the package in question. Thus, forward dependencies
           must be satisfied for a package, but reverse dependencies need not
           be. For instance, apt-cache showpkg libreadline2 would produce
           output similar to the following:

               Package: libreadline2
               Versions: 2.1-12(/var/state/apt/lists/foo_Packages),
               Reverse Depends:
                 libreadlineg2,libreadline2
                 libreadline2-altdev,libreadline2
               Dependencies:
               2.1-12 - libc5 (2 5.4.0-0) ncurses3.0 (0 (null))
               Provides:
               2.1-12 -
               Reverse Provides:
           Thus it may be seen that libreadline2, version 2.1-12, depends on
           libc5 and ncurses3.0 which must be installed for libreadline2 to
           work. In turn, libreadlineg2 and libreadline2-altdev depend on
           libreadline2. If libreadline2 is installed, libc5 and ncurses3.0
           (and ldso) must also be installed; libreadlineg2 and
           libreadline2-altdev do not have to be installed. For the specific
           meaning of the remainder of the output it is best to consult the
           apt source code.

       stats
           stats displays some statistics about the cache. No further
           arguments are expected. Statistics reported are:

           ·   Total package names is the number of package names found in the
               cache.

           ·   Normal packages is the number of regular, ordinary package
               names; these are packages that bear a one-to-one correspondence
               between their names and the names used by other packages for
               them in dependencies. The majority of packages fall into this
               category.

           ·   Pure virtual packages is the number of packages that exist only
               as a virtual package name; that is, packages only "provide" the
               virtual package name, and no package actually uses the name.
               For instance, "mail-transport-agent" in the Debian GNU/Linux
               system is a pure virtual package; several packages provide
               "mail-transport-agent", but there is no package named
               "mail-transport-agent".

           ·   Single virtual packages is the number of packages with only one
               package providing a particular virtual package. For example, in
               the Debian GNU/Linux system, "X11-text-viewer" is a virtual
               package, but only one package, xless, provides
               "X11-text-viewer".

           ·   Mixed virtual packages is the number of packages that either
               provide a particular virtual package or have the virtual
               package name as the package name. For instance, in the Debian
               GNU/Linux system, "debconf" is both an actual package, and
               provided by the debconf-tiny package.

           ·   Missing is the number of package names that were referenced in
               a dependency but were not provided by any package. Missing
               packages may be in evidence if a full distribution is not
               accessed, or if a package (real or virtual) has been dropped
               from the distribution. Usually they are referenced from
               Conflicts or Breaks statements.

           ·   Total distinct versions is the number of package versions found
               in the cache; this value is therefore at least equal to the
               number of total package names. If more than one distribution
               (both "stable" and "unstable", for instance), is being
               accessed, this value can be considerably larger than the number
               of total package names.

           ·   Total dependencies is the number of dependency relationships
               claimed by all of the packages in the cache.

       showsrc pkg(s)
           showsrc displays all the source package records that match the
           given package names. All versions are shown, as well as all records
           that declare the name to be a Binary.

       dump
           dump shows a short listing of every package in the cache. It is
           primarily for debugging.

       dumpavail
           dumpavail prints out an available list to stdout. This is suitable
           for use with dpkg(8) and is used by the dselect(8) method.

       unmet
           unmet displays a summary of all unmet dependencies in the package
           cache.

       show pkg(s)
           show performs a function similar to dpkg --print-avail; it displays
           the package records for the named packages.

       search regex [ regex ... ]
           search performs a full text search on all available package lists
           for the regex pattern given. It searches the package names and the
           descriptions for an occurrence of the regular expression and prints
           out the package name and the short description. If --full is given
           then output identical to show is produced for each matched package,
           and if --names-only is given then the long description is not
           searched, only the package name is.

           Separate arguments can be used to specify multiple search patterns
           that are and´ed together.

       depends pkg(s)
           depends shows a listing of each dependency a package has and all
           the possible other packages that can fulfill that dependency.

       rdepends pkg(s)
           rdepends shows a listing of each reverse dependency a package has.

       pkgnames [ prefix ]
           This command prints the name of each package in the system. The
           optional argument is a prefix match to filter the name list. The
           output is suitable for use in a shell tab complete function and the
           output is generated extremely quickly. This command is best used
           with the --generate option.

       dotty pkg(s)
           dotty takes a list of packages on the command line and generates
           output suitable for use by dotty from the GraphViz[1] package. The
           result will be a set of nodes and edges representing the
           relationships between the packages. By default the given packages
           will trace out all dependent packages; this can produce a very
           large graph. To limit the output to only the packages listed on the
           command line, set the APT::Cache::GivenOnly option.

           The resulting nodes will have several shapes; normal packages are
           boxes, pure provides are triangles, mixed provides are diamonds,
           missing packages are hexagons. Orange boxes mean recursion was
           stopped [leaf packages], blue lines are pre-depends, green lines
           are conflicts.

           Caution, dotty cannot graph larger sets of packages.

       policy [ pkg(s) ]
           policy is meant to help debug issues relating to the preferences
           file. With no arguments it will print out the priorities of each
           source. Otherwise it prints out detailed information about the
           priority selection of the named package.

       madison /[ pkg(s) ]
           apt-cache´s madison command attempts to mimic the output format and
           a subset of the functionality of the Debian archive management
           tool, madison. It displays available versions of a package in a
           tabular format. Unlike the original madison, it can only display
           information for the architecture for which APT has retrieved
           package lists (APT::Architecture).

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.

       -p, --pkg-cache
           Select the file to store the package cache. The package cache is
           the primary cache used by all operations. Configuration Item:
           Dir::Cache::pkgcache.

       -s, --src-cache
           Select the file to store the source cache. The source is used only
           by gencaches and it stores a parsed version of the package
           information from remote sources. When building the package cache
           the source cache is used to avoid reparsing all of the package
           files. Configuration Item: Dir::Cache::srcpkgcache.

       -q, --quiet
           Quiet; produces output suitable for logging, omitting progress
           indicators. More q´s will produce more quietness up to a maximum of
           2. You can also use -q=# to set the quietness level, overriding the
           configuration file. Configuration Item: quiet.

       -i, --important
           Print only important dependencies; for use with unmet. Causes only
           Depends and Pre-Depends relations to be printed. Configuration
           Item: APT::Cache::Important.

       -f, --full
           Print full package records when searching. Configuration Item:
           APT::Cache::ShowFull.

       -a, --all-versions
           Print full records for all available versions. This is the default;
           to turn it off, use --no-all-versions. If --no-all-versions is
           specified, only the candidate version will displayed (the one which
           would be selected for installation). This option is only applicable
           to the show command. Configuration Item: APT::Cache::AllVersions.

       -g, --generate
           Perform automatic package cache regeneration, rather than use the
           cache as it is. This is the default; to turn it off, use
           --no-generate. Configuration Item: APT::Cache::Generate.

       --names-only, -n
           Only search on the package names, not the long descriptions.
           Configuration Item: APT::Cache::NamesOnly.

       --all-names
           Make pkgnames print all names, including virtual packages and
           missing dependencies. Configuration Item: APT::Cache::AllNames.

       --recurse
           Make depends and rdepends recursive so that all packages mentioned
           are printed once. Configuration Item: APT::Cache::RecurseDepends.

       --installed
           Limit the output of depends and rdepends to packages which are
           currently installed. Configuration Item: APT::Cache::Installed.

       -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.

       /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.conf(5), sources.list(5), apt-get(8)

DIAGNOSTICS

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

BUGS

       APT bug page[2]. 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
           Author.

       APT team
           Author.

NOTES

        1. GraphViz
           http://www.research.att.com/sw/tools/graphviz/

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