Section: apt-cache (8)
Updated: 14 Jun 2006
apt-cache - APT package handling utility -- cache manipulator
apt-cache [options] [-o config=string] [-c=cfgfile] command [pkg|file(s)|regex]
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
Unless the -h, or --help option is given, one of the commands
below must be present.
- add file(s)
Adds the named package index file(s) to the package cache. This is for
Performs the same operation as apt-get check. It builds the source and
package caches from the sources in sources.list(5) and from
- showpkg pkg(s)
Displays information about the packages listed on the command-line.
Remaining arguments are package names. The available versions and reverse
dependencies of each package specified 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:
2.1-12 - libc5 (2 5.4.0-0) ncurses3.0 (0 (null))
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.
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
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,
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
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)
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
Shows a short listing of every package in the cache. It is primarily for
Prints out an available list to stdout.
Displays a summary of all unmet dependencies in the package cache.
- show pkg(s)
Displays the package records for the named packages.
- search regex [regex ...]
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
- depends pkg(s)
Shows a listing of each dependency a package has and all the possible other
packages that can fulfill that dependency.
- whatdepends pkg(s)
Shows a listing of what depends on a package.
- whatprovides pkg(s)
Shows a listing of package which provides a dependency.
- pkgnames prefix
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)
Takes a list of packages on the command line and generates output suitable
for use by dotty from the GraphViz
(http://www.research.att.com/sw/tools/graphviz/) 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
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)]
This 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
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
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 advoid 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 two. You can
also use -q=# to set the quietness level, overriding the configuration
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 be displayed (the one which would
be selected for installation). This option is only applicable to the
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.
- -n, --names-only
Only search on the package names, not the long descriptions.
Configuration Item: APT::Cache::NamesOnly.
Make pkgnames print all names, including virtual packages and missing
Configuration Item: APT::Cache::AllNames.
Make depends recursive so that all packages mentioned are printed once.
Configuration Item: APT::Cache::RecurseDepends.
- -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 arbitrary configuration option.
The syntax is -o Foo::Bar=bar.
Locations to fetch packages from.
Configuration Item: Dir::Etc::SourceList.
Storage area for state information for each package resource specified in
Configuration Item: Dir::State::Lists.
Storage area for state information in transit.
Configuration Item: Dir::State::Lists (implicit partial).
returns zero on normal operation, decimal 100 on error.
Reporting bugs in APT-RPM is best done in the APT-RPM mailinglist at
Maintainer and contributor information can be found in the credits page