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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>2012-06-09T00:00:00Z</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41 so that it can be outdated if the last update is too long ago, but in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52 implicitly by all commands needing this cache if it is missing or outdated.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>