apt-cache
APT-CACHE(E)                                         APT-CACHE(E)



NAME
       apt-cache  - APT package handling utility -- cache manipu-
       lator

SYNOPSIS
       apt-cache [ -hvs ]  [ -o=config string ]  [ -c=file ]    [
       add   file...  ]   [  gencaches  ]  [ showpkg  pkg... ]  [
       stats ]  [ dump ]  [ dumpavail ]   [  unmet  ]   [  search
       regex  ]  [ show  pkg... ]  [ showpkg  pkg... ]  [ depends
       pkg... ]  [ pkgnames  prefix ]  [ dotty  pkg... ]  [  pol-
       icy  pkgs... ]

DESCRIPTION
       apt-cache  performs a variety of operations on APT's pack-
       age 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  com-
       mands below must be present.

       add    add adds the names package index files to the pack-
              age cache.

       gencaches
              gencaches performs the  same  opration  as  apt-get
              check. It builds the source and package caches from
              the   sources   in   sources.list(t)    and    from
              /var/lib/dpkg/status.

       showpkg
              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. For-
              ward (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 show-
              pkg 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,
              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:

              o Total package names  is  the  number  of  package
                names found in the cache.

              o Normal  packages  is the number of regular, ordi-
                nary 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.

              o 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; sev-
                eral packages provide "mail-transport-agent", but
                there is no package named "mail-transport-agent".

              o Single virtual packages is the number of packages
                with only one package providing a particular vir-
                tual  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".

              o 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  sys-
                tem,  debconf is both an actual package, and pro-
                vided by the debconf-tiny package.

              o 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  evi-
                dence if a full distribution is not accesssed, or
                if a package (real or virtual) has  been  dropped
                from  the  distribution.  Usually they are refer-
                enced from Conflicts statements.

              o Total distinct versions is the number of  package
                versions found in the cache; this value is there-
                fore at least equal to the number of total  pack-
                age  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.

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


       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(g) and  is  used
              by the dselect(t) method.

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

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

       search 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 pack-
              age 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  multi-
              ple search patterns that are and'd together.

       depends
              depends  shows a listing of each dependency a pack-
              age 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  gernerates  output  suitable  for use by dotty
              from                  the                  GraphVis
              <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 packages 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, nor-
              mal packages are boxes, pure  provides  are  trian-
              gles,  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  pack-
              ages.

       policy 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.


OPTIONS
       All  command  line options may be set using the configura-
       tion 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::pkg-
              cache.

       -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,  omit-
              ting  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 config-
              uration 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::Impor-
              tant.

       -f

       --full Print full package records when searching.  Config-
              uration Item: APT::Cache::ShowFull.

       -a

       --all-versions
              Print full records for all available versions, this
              is only applicable to the show command.  Configura-
              tion 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.  Config-
              uration Item: APT::Cache::Generate.

       --names-only
              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 men-
              tioned  are  printed  once.   Configuration   Item:
              APT::Cache::RecurseDepends.

       -h

       --help Show a short usage summary.

       -v

       --version
              Show the program verison.

       -c

       --config-file
              Configuration File; Specify a configuration file to
              use.  The program will read the default  configura-
              tion  file  and  then  this configuration file. See
              apt.conf(f) for syntax information.

       -o

       --option
              Set  a  Configuration  Option;  This  will  set  an
              arbitary  configuration  option.  The  syntax is -o
              Foo::Bar=bar.

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(t) 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(f), sources.list(t), apt-get(t)

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 bug(g) com-
       mand.

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



                          12 March 2001              APT-CACHE(E)