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 adds the names package index files to the package cache.
gencaches performs the same opration 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 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:
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, 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 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
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 accesssed, or if a package
(real or virtual) has been dropped from the distribution. Usually they
are referenced from Conflicts 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.
dump shows a short listing of every package in the cache. It is
primarily for debugging.
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 displays a summary of all unmet dependencies in the
show performs a function similar to
dpkg --print-avail, it displays the package records for the
search performs a full text search on all available package
files for the regex pattern given. It searchs the package names and the
descriptions for an occurance of the string 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.
Seperate arguments can be used to specified multiple search patterns that
are and'd together.
depends shows a listing of each dependency a package has
and all the possible other packages that can fullfill that dependency.
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
extremly quickly. This command is best used with the
dotty takes a list of packages on the command line and
gernerates output suitable for use by dotty from the
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 which can produce a very large graph.
This can be turned off by setting the
The resulting nodes will have several shapse, normal packages are boxes,
pure provides are triangles, mixed provides are diamonds,
hexagons are missing packages. Orange boxes mean recursion was stopped
[leaf packages], blue lines are prre-depends, green lines are conflicts.
Caution, dotty cannot graph larger sets of packages.
policy is ment 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.
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.
Select the file to store the package cache. The package cache is the
primary cache used by all operations.
Configuration Item: Dir::Cache::pkgcache.
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.
Quiet; produces output suitable for logging, omitting progress indicators.
More qs will produce more quite up to a maximum of 2. You can also use
-q=# to set the quiet level, overriding the configuration file.
Configuration Item: quiet.
Print only important deps; for use with unmet causes only Depends and
Pre-Depends relations to be printed.
Configuration Item: APT::Cache::Important.
Print full package records when searching.
Configuration Item: APT::Cache::ShowFull.
Print full records for all available versions, this is only applicable to
the show command.
Configuration Item: APT::Cache::AllVersions.
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.
Only search on the package names, not the long description.
Configuration Item: APT::Cache::NamesOnly.
Make pkgnames print all names, including virtual packages
and missing dependencies.
Configuration Item: APT::Cache::AllNames.
Make depends recursive so that all packages mentioned are
Configuration Item: APT::Cache::RecurseDepends.
Show a short usage summary.
Show the program verison.
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 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).