mailto(apt@packages.debian.org) manpage(apt-cache)(8)(4 Dec 1998)(apt)() manpagename(apt-cache)(APT package handling utility -- cache manipulator) manpagesynopsis() apt-cache command [argument ...] manpagedescription() bf(apt-cache) performs a variety of operations on APT's package cache. bf(apt-cache) is seldom called directly; instead its operations are performed automatically by the other bf(apt) utilities. em(command) is one of: itemize( it() add file1 [file2] [...] it() gencaches it() showpkg package1 [package2] [...] it() stats it() dump it() dumpavail it() unmet it() check ) Unless the -h, or --help option is given one of the above commands must be present. startdit() dit(bf(add)) bf(add) adds the names package index files to the package cache. dit(bf(gencaches)) bf(gencaches) performs the same opration as bf(apt-get check). It builds the source and package caches from thes sources in bf(/etc/apt/sources.list) and from bf(/var/lib/dpkg/status). dit(bf(showpkg)) bf(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, bf(apt-cache showpkg libreadline2) would produce output similar to the following: verb( Package: libreadline2 Versions: 2.1-12(/var/state/apt/lists/debian.midco.net_debian_dists_slink_main_binary-i386_Packages), Reverse Depends: libreadlineg2,libreadline2 libreadline2-altdev,libreadline2 Dependencies: 2.1-12 - libc5 (2 5.4.0-0) ncurses3.0 (0 (null)) ldso (2 1.9.0-1) Provides: 2.1-12 - Reverse Provides: ) Thus it may be seen that libreadline2, version 2.1-8, depends on libc5, ncurses3.0, and ldso, 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. dit(bf(stats)) bf(stats) displays some statistics about bf(cache). No further arguments are expected. Statistics reported are: itemize( it() bf(Total package names) is the number of package names found in the cache. it() bf(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. it() bf(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". it() bf(Single virtual packages) is the number of packages with only one package providing a particular virtual package. For instance, in the Debian GNU/Linux system, "X11-text-viewer" is a virtual package, but only one package, xless, provides "X11-text-viewer". it() bf(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, e2fsprogs is both an actual package, and provided by the e2compr package. it() bf(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. it() bf(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. it() bf(Total dependencies) is the number of dependency relationships claimed by all of the packages in the cache. ) dit(bf(dump)) bf(dump) shows a short listing of every package in the cache. It is primarily for debugging. dit(bf(dumpavail)) bf(dumpavail) prints out an available list to stdout. This is suitable for use with df(dpkg) and is used by the bf(dselect) method. dit(bf(unmet)) bf(unmet) displays a summary of all unmet dependencies in the package cache. dit(bf(check)) bf(check) is a random function for testing certain aspects of the cache. Do not use it. enddit() manpageoptions() 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 bf(-f-), bf(--no-f), bf(-f=no) or several other variations. startdit() dit(bf(-h, --help)) Show a short usage summary. dit(bf(-v, --version)) Show the program verison. dit(bf(-p --pkg-cache)) Select the file to store the package cache. The package cache is the primary cache used by all operations. See bf(Dir::Cache::pkgcache). dit(bf(-s --src-cache)) Select the file to store the source cache. The source is used only by bf(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. See bf(Dir::Cache::srcpkgcache). dit(bf(-q, --quiet)) 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 bf(-q=#) to set the quiet level, overriding the configuration file. See bf(quiet). dit(bf(-i --important)) Print only important deps; for use with unmet causes only em(Depends) and em(Pre-Depends) relations to be printed. See bf(APT::Cache::Important). dit(bf(-c, --config-file)) Configuration File; Specify a configuration file to use. bf(apt-get) will read the default configuration file and then this configuration file. See bf(apt.conf(5)) for syntax information. dit(bf(-o, --option)) Set a Configuration Option; This will set an arbitary configuration option. The syntax is verb(-o Foo::Bar=bar) enddit() manpagefiles() itemize( it() /etc/apt/sources.list locations to fetch packages from it() /var/state/apt/lists/ storage area for state information for each package resource specified in it() /var/state/apt/lists/partial/ storage area for state information in transit ) manpageseealso() apt-get(8), sources.list(5), apt.conf(5) manpagediagnostics() apt-cache returns zero on normal operation, decimal 100 on error. manpagebugs() See http://bugs.debian.org/apt. If you wish to report a bug in bf(apt-cache), please see bf(/usr/doc/debian/bug-reporting.txt) or the bf(bug(1)) command. manpageauthor() apt-get was written by the APT team .