Provided by: apt_0.6.43.3ubuntu2_i386 bug


       apt-cache - APT package handling utility -- cache manipulator


       apt-cache [-hvsn] [-o=config string] [-c=file] {add file... | gencaches
                 | showpkg pkg... | showsrc pkg... | stats | dump | dumpavail
                 | unmet | search regex | show pkg... | depends pkg... |
                 rdepends pkg... | pkgnames prefix | dotty pkg... |
                 policy pkgs... | madison pkgs...}


       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)
              add  adds  the  named  package index files to the package cache.
              This is for debugging only.

              gencaches performs the  same  operation  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 pkg(s)
              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

              Package: libreadline2
              Versions: 2.1-12(/var/state/apt/lists/foo_Packages),
              Reverse Depends:
              2.1-12 - libc5 (2 5.4.0-0) ncurses3.0 (0 (null))
              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  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

              ·  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
                 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.

       showsrc pkg(s)
              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.

       dump   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)

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

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

       search regex [ regex ... ]
              search  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 and’ed together.

       depends pkg(s)
              depends shows a listing of each dependency a package has and all
              the possible other packages that can fulfill that dependency.

       rdepends pkg(s)
              rdepends  shows  a  listing of each reverse dependency a package

       pkgnames [ prefix ]
              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 extremely quickly. This command is best
              used with the --generate option.

       dotty pkg(s)
              dotty takes a list of packages on the command line and generates
              output   suitable   for   use   by   dotty  from  the  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) ]
              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(s) ]
              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:

       -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  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.  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:

       -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
              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 names,  not  the  long  descriptions.
              Configuration Item: APT::Cache::NamesOnly.

              Make  pkgnames  print  all names, including virtual packages and
              missing dependencies. Configuration Item:  APT::Cache::AllNames.

              Make  depends  and  rdepends  recursive  so  that  all  packages
              mentioned    are    printed    once.     Configuration     Item:

              Limit  the  output of depends and rdepends to packages which are
              currently installed. Configuration Item:  APT::Cache::Installed.

       -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  arbitary
              configuration option. The syntax is -o Foo::Bar=bar.


              Locations  to   fetch   packages   from.   Configuration   Item:

              Storage  area  for  state  information for each package resource
              specified     in     sources.list(5)     Configuration     Item:

              Storage  area  for  state  information in transit. Configuration
              Item: Dir::State::Lists (implicit partial).


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


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


       APT bug page: 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.