doc/apt-cache.8.xml

   1 <?xml version="1.0" encoding="utf-8" standalone="no"?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
   4 <!ENTITY % aptent SYSTEM "apt.ent"> %aptent;
   5 <!ENTITY % aptverbatiment SYSTEM "apt-verbatim.ent"> %aptverbatiment;
   6 <!ENTITY % aptvendor SYSTEM "apt-vendor.ent"> %aptvendor;
   7 ]>
   8
   9 <refentry>
  10
  11  <refentryinfo>
  12    &apt-author.jgunthorpe;
  13    &apt-author.team;
  14    &apt-email;
  15    &apt-product;
  16    <!-- The last update date -->
  17    <date>2015-10-27T00:00:00Z</date>
  18  </refentryinfo>
  19
  20  <refmeta>
  21    <refentrytitle>apt-cache</refentrytitle>
  22    <manvolnum>8</manvolnum>
  23    <refmiscinfo class="manual">APT</refmiscinfo>
  24  </refmeta>
  25
  26  <!-- Man page title -->
  27  <refnamediv>
  28     <refname>apt-cache</refname>
  29     <refpurpose>query the APT cache</refpurpose>
  30  </refnamediv>
  31
  32  &synopsis-command-apt-cache;
  33
  34  <refsect1><title>Description</title>
  35     <para>
  36        <command>apt-cache</command> performs a variety of operations on APT's
  37        package cache. <command>apt-cache</command> does not manipulate the
  38        state of the system but does provide operations to search and generate
  39        interesting output from the package metadata. The metadata is acquired
  40        and updated via the 'update' command of e.g. <command>apt-get</command>,
  41        so that it can be outdated if the last update is too long ago, but in
  42        exchange <command>apt-cache</command> works independently of the
  43        availability of the configured sources (e.g. offline).
  44     </para>
  45
  46    <para>Unless the <option>-h</option>, or <option>--help</option> option is given, one of the
  47    commands below must be present.</para>
  48
  49    <variablelist>
  50      <varlistentry><term><option>gencaches</option></term>
  51      <listitem><para><literal>gencaches</literal> creates APT's package cache. This is done
  52      implicitly by all commands needing this cache if it is missing or outdated.</para></listitem>
  53      </varlistentry>
  54
  55      <varlistentry><term><option>showpkg</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
  56      <listitem><para><literal>showpkg</literal> displays information about the packages listed on the
  57      command line. Remaining arguments are package names. The available
  58      versions and reverse dependencies of each package listed are listed, as
  59      well as forward dependencies for each version. Forward (normal)
  60      dependencies are those packages upon which the package in question
  61      depends; reverse dependencies are those packages that depend upon the
  62      package in question. Thus, forward dependencies must be satisfied for a
  63      package, but reverse dependencies need not be.
  64      For instance, <command>apt-cache showpkg libreadline2</command> would produce
  65      output similar to the following:</para>
  66
  67 <informalexample><programlisting>
  68 Package: libreadline2
  69 Versions: 2.1-12(/var/state/apt/lists/foo_Packages),
  70 Reverse Depends:
  71   libreadlineg2,libreadline2
  72   libreadline2-altdev,libreadline2
  73 Dependencies:
  74 2.1-12 - libc5 (2 5.4.0-0) ncurses3.0 (0 (null))
  75 Provides:
  76 2.1-12 -
  77 Reverse Provides:
  78 </programlisting></informalexample>
  79
  80      <para>Thus it may be seen that libreadline2, version 2.1-12, depends on
  81      libc5 and ncurses3.0 which must be installed for libreadline2 to work.
  82      In turn, libreadlineg2 and libreadline2-altdev depend on libreadline2. If
  83      libreadline2 is installed, libc5 and ncurses3.0 (and ldso) must also be
  84      installed; libreadlineg2 and libreadline2-altdev do not have to be
  85      installed. For the specific meaning of the remainder of the output it
  86      is best to consult the apt source code.</para></listitem>
  87      </varlistentry>
  88
  89      <varlistentry><term><option>stats</option></term><listitem><para><literal>stats</literal> displays some statistics about the cache.
  90      No further arguments are expected. Statistics reported are:
  91      <itemizedlist>
  92        <listitem><para><literal>Total package names</literal> is the number of package names found
  93        in the cache.</para>
  94        </listitem>
  95
  96        <listitem><para><literal>Normal packages</literal> is the number of regular, ordinary package
  97        names; these are packages that bear a one-to-one correspondence between
  98        their names and the names used by other packages for them in
  99        dependencies. The majority of packages fall into this category.</para>
 100        </listitem>
 101
 102        <listitem><para><literal>Pure virtual packages</literal> is the number of packages that exist
 103        only as a virtual package name; that is, packages only "provide" the
 104        virtual package name, and no package actually uses the name. For
 105        instance, "mail-transport-agent" in the Debian system is a
 106        pure virtual package; several packages provide "mail-transport-agent",
 107        but there is no package named "mail-transport-agent".</para>
 108        </listitem>
 109
 110        <listitem><para><literal>Single virtual packages</literal> is the number of packages with only
 111        one package providing a particular virtual package. For example, in the
 112        Debian system, "X11-text-viewer" is a virtual package, but
 113        only one package, xless, provides "X11-text-viewer".</para>
 114        </listitem>
 115
 116        <listitem><para><literal>Mixed virtual packages</literal> is the number of packages that either
 117        provide a particular virtual package or have the virtual package name
 118        as the package name. For instance, in the Debian system,
 119        "debconf" is both an actual package, and provided by the debconf-tiny
 120        package.</para>
 121        </listitem>
 122
 123        <listitem><para><literal>Missing</literal> is the number of package names that were referenced in
 124        a dependency but were not provided by any package. Missing packages may
 125        be an evidence if a full distribution is not accessed, or if a package
 126        (real or virtual) has been dropped from the distribution. Usually they
 127        are referenced from Conflicts or Breaks statements.</para>
 128        </listitem>
 129
 130        <listitem><para><literal>Total distinct</literal> versions is the number of package versions
 131        found in the cache. If more than one distribution is being accessed
 132        (for instance, "stable" and "unstable"), this value
 133        can be considerably larger than the number of total package names.</para>
 134        </listitem>
 135
 136        <listitem><para><literal>Total dependencies</literal> is the number of dependency relationships
 137        claimed by all of the packages in the cache.</para>
 138        </listitem>
 139      </itemizedlist>
 140      </para></listitem>
 141      </varlistentry>
 142
 143      <varlistentry><term><option>showsrc</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 144      <listitem><para><literal>showsrc</literal> displays all the
 145      source package records that match the given package names. All
 146      versions are shown, as well as all records that declare the name
 147      to be a binary package. Use <option>--only-source</option> to
 148      display only source package names.
 149      </para></listitem>
 150      </varlistentry>
 151
 152      <varlistentry><term><option>dump</option></term>
 153      <listitem><para><literal>dump</literal> shows a short listing of every package in the cache. It is
 154      primarily for debugging.</para></listitem>
 155      </varlistentry>
 156
 157      <varlistentry><term><option>dumpavail</option></term>
 158      <listitem><para><literal>dumpavail</literal> prints out an available list to stdout. This is
 159      suitable for use with &dpkg; and is used by the &dselect; method.</para></listitem>
 160      </varlistentry>
 161
 162      <varlistentry><term><option>unmet</option></term>
 163      <listitem><para><literal>unmet</literal> displays a summary of all unmet dependencies in the
 164      package cache.</para></listitem>
 165      </varlistentry>
 166
 167      <varlistentry><term><option>show</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 168      <listitem><para><literal>show</literal> performs a function similar to
 169      <command>dpkg --print-avail</command>; it displays the package records for the
 170      named packages.</para></listitem>
 171      </varlistentry>
 172
 173      <varlistentry><term><option>search</option> <option><replaceable>&synopsis-regex;</replaceable>…</option></term>
 174      <listitem><para><literal>search</literal> performs a full text search on all available package
 175      lists for the POSIX regex pattern given, see &regex;.
 176      It searches the package names and the
 177      descriptions for an occurrence of the regular expression and prints out
 178      the package name and the short description, including virtual package
 179      names.
 180      If <option>--full</option> is given
 181      then output identical to <literal>show</literal> is produced for each matched
 182      package, and if <option>--names-only</option> is given then the long description
 183      is not searched, only the package name and provided packages are.</para>
 184      <para>
 185      Separate arguments can be used to specify multiple search patterns that
 186      are and'ed together.</para></listitem>
 187      </varlistentry>
 188
 189      <varlistentry><term><option>depends</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 190      <listitem><para><literal>depends</literal> shows a listing of each dependency a package has
 191      and all the possible other packages that can fulfill that dependency.</para></listitem>
 192      </varlistentry>
 193
 194      <varlistentry><term><option>rdepends</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 195      <listitem><para><literal>rdepends</literal> shows a listing of each reverse dependency a
 196       package has.</para></listitem>
 197      </varlistentry>
 198
 199      <varlistentry><term><option>pkgnames</option> <optional><replaceable>&synopsis-prefix;</replaceable></optional></term>
 200      <listitem><para>This command prints the name of each package APT knows. The optional
 201      argument is a prefix match to filter the name list. The output is suitable
 202      for use in a shell tab complete function and the output is generated
 203      extremely quickly. This command is best used with the
 204      <option>--generate</option> option.</para>
 205      <para>Note that a package which APT knows of is not necessarily available to download,
 206      installable or installed, e.g. virtual packages are also listed in the generated list.
 207      </para></listitem>
 208      </varlistentry>
 209
 210      <varlistentry><term><option>dotty</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 211      <listitem><para><literal>dotty</literal> takes a list of packages on the command line and
 212      generates output suitable for use by dotty from the
 213      <ulink url="http://www.research.att.com/sw/tools/graphviz/">GraphViz</ulink>
 214      package. The result will be a set of nodes and edges representing the
 215      relationships between the packages. By default the given packages will
 216      trace out all dependent packages; this can produce a very large graph.
 217      To limit the output to only the packages listed on the command line,
 218      set the <literal>APT::Cache::GivenOnly</literal> option.</para>
 219
 220      <para>The resulting nodes will have several shapes; normal packages are boxes,
 221      pure virtual packages are triangles, mixed virtual packages are diamonds,
 222      missing packages are hexagons. Orange boxes mean recursion was stopped
 223      (leaf packages), blue lines are pre-depends, green lines are conflicts.</para>
 224
 225      <para>Caution, dotty cannot graph larger sets of packages.</para></listitem>
 226      </varlistentry>
 227
 228      <varlistentry><term><option>xvcg</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 229          <listitem><para>The same as <literal>dotty</literal>, only for xvcg from the
 230          <ulink url="http://rw4.cs.uni-sb.de/users/sander/html/gsvcg1.html">VCG tool</ulink>.
 231          </para></listitem></varlistentry>
 232
 233          <varlistentry><term><option>policy</option> <optional><replaceable>&synopsis-pkg;</replaceable>…</optional></term>
 234      <listitem><para><literal>policy</literal> is meant to help debug issues relating to the
 235      preferences file. With no arguments it will print out the
 236      priorities of each source. Otherwise it prints out detailed information
 237      about the priority selection of the named package.</para></listitem>
 238      </varlistentry>
 239
 240      <varlistentry><term><option>madison</option> <option><replaceable>&synopsis-pkg;</replaceable>…</option></term>
 241      <listitem><para><literal>apt-cache</literal>'s <literal>madison</literal> command attempts to mimic
 242      the output format and a subset of the functionality of the Debian
 243      archive management tool, <literal>madison</literal>.  It displays
 244      available versions of a package in a tabular format.  Unlike the
 245      original <literal>madison</literal>, it can only display information for
 246      the architecture for which APT has retrieved package lists
 247      (<literal>APT::Architecture</literal>).</para></listitem>
 248      </varlistentry>
 249    </variablelist>
 250  </refsect1>
 251
 252  <refsect1><title>options</title>
 253    &apt-cmdblurb;
 254
 255    <variablelist>
 256      <varlistentry><term><option>-p</option></term><term><option>--pkg-cache</option></term>
 257      <listitem><para>Select the file to store the package cache. The package cache is the
 258      primary cache used by all operations.
 259      Configuration Item: <literal>Dir::Cache::pkgcache</literal>.</para></listitem>
 260      </varlistentry>
 261
 262      <varlistentry><term><option>-s</option></term><term><option>--src-cache</option></term>
 263      <listitem><para>Select the file to store the source cache. The source is used only by
 264      <literal>gencaches</literal> and it stores a parsed version of the package
 265      information from remote sources. When building the package cache the
 266      source cache is used to avoid reparsing all of the package files.
 267      Configuration Item: <literal>Dir::Cache::srcpkgcache</literal>.</para></listitem>
 268      </varlistentry>
 269
 270      <varlistentry><term><option>-q</option></term><term><option>--quiet</option></term>
 271      <listitem><para>Quiet; produces output suitable for logging, omitting progress indicators.
 272      More q's will produce more quietness up to a maximum of 2. You can also use
 273      <option>-q=#</option> to set the quietness level, overriding the configuration file.
 274      Configuration Item: <literal>quiet</literal>.</para></listitem>
 275      </varlistentry>
 276
 277      <varlistentry><term><option>-i</option></term><term><option>--important</option></term>
 278      <listitem><para>Print only important dependencies; for use with <literal>unmet</literal>
 279      and <literal>depends</literal>. Causes only Depends and
 280      Pre-Depends relations to be printed.
 281      Configuration Item: <literal>APT::Cache::Important</literal>.</para></listitem>
 282      </varlistentry>
 283
 284      <varlistentry><term><option>--no-pre-depends</option></term>
 285                    <term><option>--no-depends</option></term>
 286                    <term><option>--no-recommends</option></term>
 287                    <term><option>--no-suggests</option></term>
 288                    <term><option>--no-conflicts</option></term>
 289                    <term><option>--no-breaks</option></term>
 290                    <term><option>--no-replaces</option></term>
 291                    <term><option>--no-enhances</option></term>
 292                    <listitem><para>Per default the <command>depends</command> and
 293      <command>rdepends</command> print all dependencies. This can be tweaked with
 294      these flags which will omit the specified dependency type.
 295      Configuration Item: <literal>APT::Cache::Show<replaceable>DependencyType</replaceable></literal>
 296      e.g. <literal>APT::Cache::ShowRecommends</literal>.</para></listitem>
 297      </varlistentry>
 298
 299      <varlistentry><term><option>--implicit</option></term>
 300         <listitem><para>Per default <command>depends</command> and <command>rdepends</command>
 301               print only dependencies explicitly expressed in the metadata. With this flag
 302               it will also show dependencies implicitely added based on the encountered data.
 303               A <literal>Conflicts: foo</literal> e.g. expresses implicitely that this package
 304               also conflicts with the package foo from any other architecture.
 305               Configuration Item: <literal>APT::Cache::ShowImplicit</literal>.
 306         </para></listitem>
 307      </varlistentry>
 308
 309      <varlistentry><term><option>-f</option></term><term><option>--full</option></term>
 310      <listitem><para>Print full package records when searching.
 311      Configuration Item: <literal>APT::Cache::ShowFull</literal>.</para></listitem>
 312      </varlistentry>
 313
 314      <varlistentry><term><option>-a</option></term><term><option>--all-versions</option></term>
 315      <listitem><para>Print full records for all available versions. This is the
 316      default; to turn it off, use <option>--no-all-versions</option>.
 317      If <option>--no-all-versions</option> is specified, only the candidate version
 318      will be displayed (the one which would be selected for installation).
 319      This option is only applicable to  the <literal>show</literal> command.
 320      Configuration Item: <literal>APT::Cache::AllVersions</literal>.</para></listitem>
 321      </varlistentry>
 322
 323      <varlistentry><term><option>-g</option></term><term><option>--generate</option></term>
 324      <listitem><para>Perform automatic package cache regeneration, rather than use the cache
 325      as it is. This is the default; to turn it off, use <option>--no-generate</option>.
 326      Configuration Item: <literal>APT::Cache::Generate</literal>.</para></listitem>
 327      </varlistentry>
 328
 329      <varlistentry><term><option>--names-only</option></term><term><option>-n</option></term>
 330      <listitem><para>Only search on the package and provided package names, not the long descriptions.
 331      Configuration Item: <literal>APT::Cache::NamesOnly</literal>.</para></listitem>
 332      </varlistentry>
 333
 334      <varlistentry><term><option>--all-names</option></term>
 335      <listitem><para>Make <literal>pkgnames</literal> print all names, including virtual packages
 336      and missing dependencies.
 337      Configuration Item: <literal>APT::Cache::AllNames</literal>.</para></listitem>
 338      </varlistentry>
 339
 340      <varlistentry><term><option>--recurse</option></term>
 341      <listitem><para>Make <literal>depends</literal> and <literal>rdepends</literal> recursive so
 342      that all packages mentioned are printed once.
 343      Configuration Item: <literal>APT::Cache::RecurseDepends</literal>.</para></listitem>
 344      </varlistentry>
 345
 346       <varlistentry><term><option>--installed</option></term>
 347       <listitem><para>
 348       Limit the output of <literal>depends</literal> and <literal>rdepends</literal> to
 349       packages which are currently installed.
 350       Configuration Item: <literal>APT::Cache::Installed</literal>.</para></listitem>
 351       </varlistentry>
 352
 353      &apt-commonoptions;
 354
 355    </variablelist>
 356  </refsect1>
 357
 358  <refsect1><title>Files</title>
 359    <variablelist>
 360      &file-sourceslist;
 361      &file-statelists;
 362    </variablelist>
 363  </refsect1>
 364
 365  <refsect1><title>See Also</title>
 366    <para>&apt-conf;, &sources-list;, &apt-get;
 367    </para>
 368  </refsect1>
 369
 370  <refsect1><title>Diagnostics</title>
 371    <para><command>apt-cache</command> returns zero on normal operation, decimal 100 on error.
 372    </para>
 373  </refsect1>
 374
 375  &manbugs;
 376
 377 </refentry>