apt-cache (8)





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 ... | showpkg  pkg ... |
       depends  pkg ... | pkgnames  prefix | dotty  pkg ... | policy  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    add  adds  the  named  package index files to the package cache.
              This is for debugging only.

       gencaches
              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
              showpkg displays information about the packages  listed  on  the
              command  line. Remaining arguments are package names. The avail-
              able 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 depen-
              dencies need not be.  For instance, apt-cache  showpkg  libread-
              line2 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
                the cache.

              · Normal  packages  is  the  number of regular, ordinary package
                names; these are packages that bear  a  one-to-one  correspon-
                dence 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  "pro-
                vide"  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  exam-
                ple,  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 pack-
                age  name  as  the  package  name. For instance, in the Debian
                GNU/Linux system, debconf is both an actual package, and  pro-
                vided 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
                accesssed, or if a package (real or virtual) has been  dropped
                from  the  distribution. Usually they are referenced from Con-
                flicts 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  distribu-
                tion  (both  "stable"  and "unstable", for instance), is being
                accessed, this value can be considerably larger than the  num-
                ber of total package names.

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

       showsrc
              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.  named packages.

       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 suit-
              able for use with dpkg(8) and is used by the dselect(8)  method.

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

       pkgnames
              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 --generate option.

       dotty  dotty  takes  a list of packages on the command line and gerner-
              ates  output  suitable  for  use  by  dotty  from  the  GraphViz
              <URL: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 pack-
              ages will trace out all dependent packages which can  produce  a
              very  large  graph.   This  can  be  turned  off  by setting the
              APT::Cache::GivenOnly option.

       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 con-
       flicts.

       Caution, dotty cannot graph larger sets of packages.

              policy policy is ment to help debug issues relating to the pref-
                     erences  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.


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

       --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 -q=# to set the quiet level, overriding the
              configuration file.  Configuration Item: quiet.

       -i

       --important
              Print only important  deps;  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 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 description.
              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  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


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

       See the APT bug page <URL:http://bugs.debian.org/apt>.  If you wish  to
       report a bug in APT, please see /usr/share/doc/debian/bug-reporting.txt
       or the reportbug(1) command.


AUTHOR

       APT was written by the APT team <apt@packages.debian.org>.

                                17 August 2003                    apt-cache(8)