apt-cache - Man Page

• Search for a package in your current sources: apt-cache search query
• Show information about a package: apt-cache show package
• Show whether a package is installed and up to date: apt-cache policy package
• Show dependencies for a package: apt-cache depends package
• Show packages that depend on a particular package: apt-cache rdepends package

tldr.sh

apt-cache [-agipns] [-o=config_string] [-c=config_file] {gencaches | showpkg pkg...  | showsrc pkg...  | stats | dump | dumpavail | unmet | search regex...  | show pkg [{=pkg_version_number | /target_release}]...  | depends pkg [{=pkg_version_number | /target_release}]...  | rdepends pkg [{=pkg_version_number | /target_release}]...  | pkgnames [prefix]  | dotty pkg [{=pkg_version_number | /target_release}]...  | xvcg pkg [{=pkg_version_number | /target_release}]...  | policy [pkg...]  | madison pkg...  | {-v | --version} | {-h | --help}}

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​. The metadata is acquired and updated via the 'update' command of e​.g​. apt-get, so that it can be outdated if the last update is too long ago, but in exchange apt-cache works independently of the availability of the configured sources (e​.g​. offline)​.

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

gencaches

gencaches creates APT's package cache​. This is done implicitly by all commands needing this cache if it is missing or outdated​.

showpkg pkg​...

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 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 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 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 an 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​. If more than one distribution is being accessed (for instance, "stable" and "unstable"), 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​...

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 package​. Use --only-source to display only source package names​.

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(1) and is used by the dselect(1) method​.

unmet

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

show pkg​...

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

search regex​...

search performs a full text search on all available package lists for the POSIX regex pattern given, see regex(7)​. 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, including virtual package names​. 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 and provided packages are​.

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

depends pkg​...

depends shows a listing of each dependency a package has and all the possible other packages that can fulfill that dependency​.

rdepends pkg​...

rdepends shows a listing of each reverse dependency a package has​.

pkgnames [prefix]

This command prints the name of each package APT knows​. 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​.

Note that a package which APT knows of is not necessarily available to download, installable or installed, e​.g​. virtual packages are also listed in the generated list​.

dotty pkg​...

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 virtual packages are triangles, mixed virtual packages 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​.

xvcg pkg​...

The same as dotty, only for xvcg from the VCG tool​^[2]​.

policy [pkg​...]

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​...

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)​.

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 and depends​. Causes only Depends and Pre-Depends relations to be printed​. Configuration Item: APT::Cache::Important​.

--no-pre-depends,  --no-depends,  --no-recommends,  --no-suggests,  --no-conflicts,  --no-breaks,  --no-replaces,  --no-enhances

Per default the depends and rdepends print all dependencies​. This can be tweaked with these flags which will omit the specified dependency type​. Configuration Item: APT::Cache::ShowDependencyType e​.g​. APT::Cache::ShowRecommends​.

--implicit

Per default depends and rdepends print only dependencies explicitly expressed in the metadata​. With this flag it will also show dependencies implicitly added based on the encountered data​. A Conflicts: foo e​.g​. expresses implicitly that this package also conflicts with the package foo from any other architecture​. Configuration Item: APT::Cache::ShowImplicit​.

-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 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 and provided 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​.

--with-source filename

Adds the given file as a source for metadata​. Can be repeated to add multiple files​. Supported are currently *​.deb, *​.dsc, *​.changes, Sources and Packages files as well as source package directories​. Files are matched based on their name only, not their content!

Sources and Packages can be compressed in any format apt supports as long as they have the correct extension​. If you need to store multiple of these files in one directory you can prefix a name of your choice with the last character being an underscore ("_")​. Example: my​.example_Packages​.xz

Note that these sources are treated as trusted (see apt-secure(8))​. Configuration Item: APT::Sources::With​.

-h,  --help

Show a short usage summary​.

-v,  --version

Show the program version​.

--audit

Show audit (and notice) messages​. This overrides the quiet option, but only for notice messages, not progress ones​.

-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​.

--cli-version

Requests a specific CLI version​. This is a pattern that takes a MAJOR​.MINOR version​. You may omit the MINOR version, in which case the latest supported minor level will be used​.

Version tracks are presented as follows: The version 3​.2 has equivalent versions 0​.32, 1​.22, and 2​.12, implementing new features for their specified major versions​.

A special case is the X​.9 version pattern: A version like 2​.9 is followed by 3​.0, but 2​.10 follows directly on 2​.8; given that we use odd version numbers as development series (2​.9 is the 3​.0 development series)​.

This feature has been introduced in APT 3​.1​.10, and replaces the binary-specific configuration​. You may use the APT::Version to similar effect on older binaries, for example, use -o APT::Version=2 to make apt(8) behave like the 2​.x series​.

The default value is the current APT version for apt(8) and 0​.(10 * major + minor) for the classic commands​. The 0​.X series is soft-deprecated and the other commands will roll over to the 2​.x series in the future​.

--no-color,  --color

Turn colors on or off​. Colors are on by default on supported terminals for apt(8) and can also be disabled using the NO_COLOR or APT_NO_COLOR environment variables, or further configured by the APT::Color configuration option and scope, see apt.conf(5) for information on that​.

/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​.

/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 (partial will be implicitly appended)

apt.conf(5), sources.list(5), apt-get(8), apt-patterns(7)

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

APT bug page​^[3]​. If you wish to report a bug in APT, please see /usr/share/doc/debian/bug-reporting​.txt or the reportbug(1) command​.

Jason Gunthorpe

APT team

1. GraphViz
   https://graphviz.org/
2. VCG tool
   https://www.rw.cdl.uni-saarland.de/people/sander/private/html/gsvcg1.html
3. APT bug page
   https://bugs.debian.org/src:apt

apt(8), apt.conf(5), apt-get(8), apt_preferences(5), debcheckout(1).