apt-get.8.xml 25 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494
  1. <?xml version="1.0" encoding="utf-8" standalone="no"?>
  2. <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
  3. "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [
  4. <!ENTITY % aptent SYSTEM "apt.ent">
  5. %aptent;
  6. ]>
  7. <refentry>
  8. <refentryinfo>
  9. &apt-author.jgunthorpe;
  10. &apt-author.team;
  11. &apt-email;
  12. &apt-product;
  13. <!-- The last update date -->
  14. <date>29 February 2004</date>
  15. </refentryinfo>
  16. <refmeta>
  17. <refentrytitle>apt-get</refentrytitle>
  18. <manvolnum>8</manvolnum>
  19. </refmeta>
  20. <!-- Man page title -->
  21. <refnamediv>
  22. <refname>apt-get</refname>
  23. <refpurpose>APT package handling utility -- command-line interface</refpurpose>
  24. </refnamediv>
  25. <!-- Arguments -->
  26. <refsynopsisdiv>
  27. <cmdsynopsis>
  28. <command>apt-get</command>
  29. <arg><option>-hvs</option></arg>
  30. <arg><option>-o=<replaceable>config string</replaceable></option></arg>
  31. <arg><option>-c=<replaceable>file</replaceable></option></arg>
  32. <group choice="req">
  33. <arg>update</arg>
  34. <arg>upgrade</arg>
  35. <arg>dselect-upgrade</arg>
  36. <arg>install <arg choice="plain" rep="repeat"><replaceable>pkg</replaceable></arg></arg>
  37. <arg>remove <arg choice="plain" rep="repeat"><replaceable>pkg</replaceable></arg></arg>
  38. <arg>source <arg choice="plain" rep="repeat"><replaceable>pkg</replaceable></arg></arg>
  39. <arg>build-dep <arg choice="plain" rep="repeat"><replaceable>pkg</replaceable></arg></arg>
  40. <arg>check</arg>
  41. <arg>clean</arg>
  42. <arg>autoclean</arg>
  43. <arg>autoremove</arg>
  44. </group>
  45. </cmdsynopsis>
  46. </refsynopsisdiv>
  47. <refsect1><title>Description</title>
  48. <para><command>apt-get</command> is the command-line tool for handling packages, and may be
  49. considered the user's "back-end" to other tools using the APT
  50. library. Several "front-end" interfaces exist, such as dselect(8),
  51. aptitude, synaptic, gnome-apt and wajig.</para>
  52. <para>Unless the <option>-h</option>, or <option>--help</option> option is given, one of the
  53. commands below must be present.</para>
  54. <variablelist>
  55. <varlistentry><term>update</term>
  56. <listitem><para><literal>update</literal> is used to resynchronize the package index files from
  57. their sources. The indexes of available packages are fetched from the
  58. location(s) specified in <filename>/etc/apt/sources.list</filename>.
  59. For example, when using a Debian archive, this command retrieves and
  60. scans the <filename>Packages.gz</filename> files, so that information about new
  61. and updated packages is available. An <literal>update</literal> should always be
  62. performed before an <literal>upgrade</literal> or <literal>dist-upgrade</literal>. Please
  63. be aware that the overall progress meter will be incorrect as the size
  64. of the package files cannot be known in advance.</para></listitem>
  65. </varlistentry>
  66. <varlistentry><term>upgrade</term>
  67. <listitem><para><literal>upgrade</literal> is used to install the newest versions of all packages
  68. currently installed on the system from the sources enumerated in
  69. <filename>/etc/apt/sources.list</filename>. Packages currently installed with
  70. new versions available are retrieved and upgraded; under no circumstances
  71. are currently installed packages removed, or packages not already installed
  72. retrieved and installed. New versions of currently installed packages that
  73. cannot be upgraded without changing the install status of another package
  74. will be left at their current version. An <literal>update</literal> must be
  75. performed first so that <command>apt-get</command> knows that new versions of packages are
  76. available.</para></listitem>
  77. </varlistentry>
  78. <varlistentry><term>dselect-upgrade</term>
  79. <listitem><para><literal>dselect-upgrade</literal>
  80. is used in conjunction with the traditional Debian packaging
  81. front-end, &dselect;. <literal>dselect-upgrade</literal>
  82. follows the changes made by &dselect; to the <literal>Status</literal>
  83. field of available packages, and performs the actions necessary to realize
  84. that state (for instance, the removal of old and the installation of new
  85. packages).</para></listitem>
  86. </varlistentry>
  87. <varlistentry><term>dist-upgrade</term>
  88. <listitem><para><literal>dist-upgrade</literal> in addition to performing the function of
  89. <literal>upgrade</literal>, also intelligently handles changing dependencies
  90. with new versions of packages; <command>apt-get</command> has a "smart" conflict
  91. resolution system, and it will attempt to upgrade the most important
  92. packages at the expense of less important ones if necessary.
  93. The <filename>/etc/apt/sources.list</filename> file contains a list of locations
  94. from which to retrieve desired package files.
  95. See also &apt-preferences; for a mechanism for
  96. overriding the general settings for individual packages.</para></listitem>
  97. </varlistentry>
  98. <varlistentry><term>install</term>
  99. <listitem><para><literal>install</literal> is followed by one or more packages desired for
  100. installation. Each package is a package name, not a fully qualified
  101. filename (for instance, in a Debian GNU/Linux system, libc6 would be the
  102. argument provided, not <literal>libc6_1.9.6-2.deb</literal>) All packages required
  103. by the package(s) specified for installation will also be retrieved and
  104. installed. The <filename>/etc/apt/sources.list</filename> file is used to locate
  105. the desired packages. If a hyphen is appended to the package name (with
  106. no intervening space), the identified package will be removed if it is
  107. installed. Similarly a plus sign can be used to designate a package to
  108. install. These latter features may be used to override decisions made by
  109. apt-get's conflict resolution system.</para>
  110. <para>A specific version of a package can be selected for installation by
  111. following the package name with an equals and the version of the package
  112. to select. This will cause that version to be located and selected for
  113. install. Alternatively a specific distribution can be selected by
  114. following the package name with a slash and the version of the
  115. distribution or the Archive name (stable, testing, unstable).</para>
  116. <para>Both of the version selection mechanisms can downgrade packages and must
  117. be used with care.</para>
  118. <para>Finally, the &apt-preferences; mechanism allows you to
  119. create an alternative installation policy for
  120. individual packages.</para>
  121. <para>If no package matches the given expression and the expression contains one
  122. of '.', '?' or '*' then it is assumed to be a POSIX regular expression,
  123. and it is applied
  124. to all package names in the database. Any matches are then installed (or
  125. removed). Note that matching is done by substring so 'lo.*' matches 'how-lo'
  126. and 'lowest'. If this is undesired, anchor the regular expression
  127. with a '^' or '$' character, or create a more specific regular expression.</para></listitem>
  128. </varlistentry>
  129. <varlistentry><term>remove</term>
  130. <listitem><para><literal>remove</literal> is identical to <literal>install</literal> except that packages are
  131. removed instead of installed. If a plus sign is appended to the package
  132. name (with no intervening space), the identified package will be
  133. installed instead of removed.</para></listitem>
  134. </varlistentry>
  135. <varlistentry><term>source</term>
  136. <listitem><para><literal>source</literal> causes <command>apt-get</command> to fetch source packages. APT
  137. will examine the available packages to decide which source package to
  138. fetch. It will then find and download into the current directory the
  139. newest available version of that source package. Source packages are
  140. tracked separately from binary packages via <literal>deb-src</literal> type lines
  141. in the &sources-list; file. This probably will mean that you will not
  142. get the same source as the package you have installed or as you could
  143. install. If the --compile options is specified then the package will be
  144. compiled to a binary .deb using dpkg-buildpackage, if --download-only is
  145. specified then the source package will not be unpacked.</para>
  146. <para>A specific source version can be retrieved by postfixing the source name
  147. with an equals and then the version to fetch, similar to the mechanism
  148. used for the package files. This enables exact matching of the source
  149. package name and version, implicitly enabling the
  150. <literal>APT::Get::Only-Source</literal> option.</para>
  151. <para>Note that source packages are not tracked like binary packages, they
  152. exist only in the current directory and are similar to downloading source
  153. tar balls.</para></listitem>
  154. </varlistentry>
  155. <varlistentry><term>build-dep</term>
  156. <listitem><para><literal>build-dep</literal> causes apt-get to install/remove packages in an
  157. attempt to satisfy the build dependencies for a source package.</para></listitem>
  158. </varlistentry>
  159. <varlistentry><term>check</term>
  160. <listitem><para><literal>check</literal> is a diagnostic tool; it updates the package cache and checks
  161. for broken dependencies.</para></listitem>
  162. </varlistentry>
  163. <varlistentry><term>clean</term>
  164. <listitem><para><literal>clean</literal> clears out the local repository of retrieved package
  165. files. It removes everything but the lock file from
  166. <filename>&cachedir;/archives/</filename> and
  167. <filename>&cachedir;/archives/partial/</filename>. When APT is used as a
  168. &dselect; method, <literal>clean</literal> is run automatically.
  169. Those who do not use dselect will likely want to run <literal>apt-get clean</literal>
  170. from time to time to free up disk space.</para></listitem>
  171. </varlistentry>
  172. <varlistentry><term>autoclean</term>
  173. <listitem><para>Like <literal>clean</literal>, <literal>autoclean</literal> clears out the local
  174. repository of retrieved package files. The difference is that it only
  175. removes package files that can no longer be downloaded, and are largely
  176. useless. This allows a cache to be maintained over a long period without
  177. it growing out of control. The configuration option
  178. <literal>APT::Clean-Installed</literal> will prevent installed packages from being
  179. erased if it is set to off.</para></listitem>
  180. </varlistentry>
  181. <varlistentry><term>autoremove</term>
  182. <listitem><para><literal>autoremove</literal> is used to remove packages that were automatically
  183. installed to satisfy dependencies for some package and that are no more needed.</para></listitem>
  184. </varlistentry>
  185. </variablelist>
  186. </refsect1>
  187. <refsect1><title>options</title>
  188. &apt-cmdblurb;
  189. <variablelist>
  190. <varlistentry><term><option>-d</option></term><term><option>--download-only</option></term>
  191. <listitem><para>Download only; package files are only retrieved, not unpacked or installed.
  192. Configuration Item: <literal>APT::Get::Download-Only</literal>.</para></listitem>
  193. </varlistentry>
  194. <varlistentry><term><option>-f</option></term><term><option>--fix-broken</option></term>
  195. <listitem><para>Fix; attempt to correct a system with broken dependencies in
  196. place. This option, when used with install/remove, can omit any packages
  197. to permit APT to deduce a likely solution. Any Package that are specified
  198. must completely correct the problem. The option is sometimes necessary when
  199. running APT for the first time; APT itself does not allow broken package
  200. dependencies to exist on a system. It is possible that a system's
  201. dependency structure can be so corrupt as to require manual intervention
  202. (which usually means using &dselect; or <command>dpkg --remove</command> to eliminate some of
  203. the offending packages). Use of this option together with <option>-m</option> may produce an
  204. error in some situations.
  205. Configuration Item: <literal>APT::Get::Fix-Broken</literal>.</para></listitem>
  206. </varlistentry>
  207. <varlistentry><term><option>-m</option></term><term><option>--ignore-missing</option></term>
  208. <term><option>--fix-missing</option></term>
  209. <listitem><para>Ignore missing packages; If packages cannot be retrieved or fail the
  210. integrity check after retrieval (corrupted package files), hold back
  211. those packages and handle the result. Use of this option together with
  212. <option>-f</option> may produce an error in some situations. If a package is
  213. selected for installation (particularly if it is mentioned on the
  214. command line) and it could not be downloaded then it will be silently
  215. held back.
  216. Configuration Item: <literal>APT::Get::Fix-Missing</literal>.</para></listitem>
  217. </varlistentry>
  218. <varlistentry><term><option>--no-download</option></term>
  219. <listitem><para>Disables downloading of packages. This is best used with
  220. <option>--ignore-missing</option> to force APT to use only the .debs it has
  221. already downloaded.
  222. Configuration Item: <literal>APT::Get::Download</literal>.</para></listitem>
  223. </varlistentry>
  224. <varlistentry><term><option>-q</option></term><term><option>--quiet</option></term>
  225. <listitem><para>Quiet; produces output suitable for logging, omitting progress indicators.
  226. More q's will produce more quiet up to a maximum of 2. You can also use
  227. <option>-q=#</option> to set the quiet level, overriding the configuration file.
  228. Note that quiet level 2 implies <option>-y</option>, you should never use -qq
  229. without a no-action modifier such as -d, --print-uris or -s as APT may
  230. decided to do something you did not expect.
  231. Configuration Item: <literal>quiet</literal>.</para></listitem>
  232. </varlistentry>
  233. <varlistentry><term><option>-s</option></term>
  234. <term><option>--simulate</option></term>
  235. <term><option>--just-print</option></term>
  236. <term><option>--dry-run</option></term>
  237. <term><option>--recon</option></term>
  238. <term><option>--no-act</option></term>
  239. <listitem><para>No action; perform a simulation of events that would occur but do not
  240. actually change the system.
  241. Configuration Item: <literal>APT::Get::Simulate</literal>.</para>
  242. <para>Simulate prints out
  243. a series of lines each one representing a dpkg operation, Configure (Conf),
  244. Remove (Remv), Unpack (Inst). Square brackets indicate broken packages with
  245. and empty set of square brackets meaning breaks that are of no consequence
  246. (rare).</para></listitem>
  247. </varlistentry>
  248. <varlistentry><term><option>-y</option></term><term><option>--yes</option></term>
  249. <term><option>--assume-yes</option></term>
  250. <listitem><para>Automatic yes to prompts; assume "yes" as answer to all prompts and run
  251. non-interactively. If an undesirable situation, such as changing a held
  252. package, trying to install a unauthenticated package or removing an essential package
  253. occurs then <literal>apt-get</literal> will abort.
  254. Configuration Item: <literal>APT::Get::Assume-Yes</literal>.</para></listitem>
  255. </varlistentry>
  256. <varlistentry><term><option>-u</option></term><term><option>--show-upgraded</option></term>
  257. <listitem><para>Show upgraded packages; Print out a list of all packages that are to be
  258. upgraded.
  259. Configuration Item: <literal>APT::Get::Show-Upgraded</literal>.</para></listitem>
  260. </varlistentry>
  261. <varlistentry><term><option>-V</option></term><term><option>--verbose-versions</option></term>
  262. <listitem><para>Show full versions for upgraded and installed packages.
  263. Configuration Item: <literal>APT::Get::Show-Versions</literal>.</para></listitem>
  264. </varlistentry>
  265. <varlistentry><term><option>-b</option></term><term><option>--compile</option></term>
  266. <term><option>--build</option></term>
  267. <listitem><para>Compile source packages after downloading them.
  268. Configuration Item: <literal>APT::Get::Compile</literal>.</para></listitem>
  269. </varlistentry>
  270. <varlistentry><term><option>--ignore-hold</option></term>
  271. <listitem><para>Ignore package Holds; This causes <command>apt-get</command> to ignore a hold
  272. placed on a package. This may be useful in conjunction with
  273. <literal>dist-upgrade</literal> to override a large number of undesired holds.
  274. Configuration Item: <literal>APT::Ignore-Hold</literal>.</para></listitem>
  275. </varlistentry>
  276. <varlistentry><term><option>--no-upgrade</option></term>
  277. <listitem><para>Do not upgrade packages; When used in conjunction with <literal>install</literal>,
  278. <literal>no-upgrade</literal> will prevent packages on the command line
  279. from being upgraded if they are already installed.
  280. Configuration Item: <literal>APT::Get::Upgrade</literal>.</para></listitem>
  281. </varlistentry>
  282. <varlistentry><term><option>--force-yes</option></term>
  283. <listitem><para>Force yes; This is a dangerous option that will cause apt to continue
  284. without prompting if it is doing something potentially harmful. It
  285. should not be used except in very special situations. Using
  286. <literal>force-yes</literal> can potentially destroy your system!
  287. Configuration Item: <literal>APT::Get::force-yes</literal>.</para></listitem>
  288. </varlistentry>
  289. <varlistentry><term><option>--print-uris</option></term>
  290. <listitem><para>Instead of fetching the files to install their URIs are printed. Each
  291. URI will have the path, the destination file name, the size and the expected
  292. md5 hash. Note that the file name to write to will not always match
  293. the file name on the remote site! This also works with the
  294. <literal>source</literal> and <literal>update</literal> commands. When used with the
  295. <literal>update</literal> command the MD5 and size are not included, and it is
  296. up to the user to decompress any compressed files.
  297. Configuration Item: <literal>APT::Get::Print-URIs</literal>.</para></listitem>
  298. </varlistentry>
  299. <varlistentry><term><option>--purge</option></term>
  300. <listitem><para>Use purge instead of remove for anything that would be removed.
  301. An asterisk ("*") will be displayed next to packages which are
  302. scheduled to be purged.
  303. Configuration Item: <literal>APT::Get::Purge</literal>.</para></listitem>
  304. </varlistentry>
  305. <varlistentry><term><option>--reinstall</option></term>
  306. <listitem><para>Re-Install packages that are already installed and at the newest version.
  307. Configuration Item: <literal>APT::Get::ReInstall</literal>.</para></listitem>
  308. </varlistentry>
  309. <varlistentry><term><option>--list-cleanup</option></term>
  310. <listitem><para>This option defaults to on, use <literal>--no-list-cleanup</literal> to turn it
  311. off. When on <command>apt-get</command> will automatically manage the contents of
  312. <filename>&statedir;/lists</filename> to ensure that obsolete files are erased.
  313. The only reason to turn it off is if you frequently change your source
  314. list.
  315. Configuration Item: <literal>APT::Get::List-Cleanup</literal>.</para></listitem>
  316. </varlistentry>
  317. <varlistentry><term><option>-t</option></term>
  318. <term><option>--target-release</option></term>
  319. <term><option>--default-release</option></term>
  320. <listitem><para>This option controls the default input to the policy engine, it creates
  321. a default pin at priority 990 using the specified release string. The
  322. preferences file may further override this setting. In short, this option
  323. lets you have simple control over which distribution packages will be
  324. retrieved from. Some common examples might be
  325. <option>-t '2.1*'</option> or <option>-t unstable</option>.
  326. Configuration Item: <literal>APT::Default-Release</literal>;
  327. see also the &apt-preferences; manual page.</para></listitem>
  328. </varlistentry>
  329. <varlistentry><term><option>--trivial-only</option></term>
  330. <listitem><para>
  331. Only perform operations that are 'trivial'. Logically this can be considered
  332. related to <option>--assume-yes</option>, where <option>--assume-yes</option> will answer
  333. yes to any prompt, <option>--trivial-only</option> will answer no.
  334. Configuration Item: <literal>APT::Get::Trivial-Only</literal>.</para></listitem>
  335. </varlistentry>
  336. <varlistentry><term><option>--no-remove</option></term>
  337. <listitem><para>If any packages are to be removed apt-get immediately aborts without
  338. prompting.
  339. Configuration Item: <literal>APT::Get::Remove</literal>.</para></listitem>
  340. </varlistentry>
  341. <varlistentry><term><option>--auto-remove</option></term>
  342. <listitem><para>If the command is either <literal>install</literal> or <literal>remove</literal>,
  343. then this option acts like running <literal>autoremove</literal> command, removing the unused
  344. dependency packages. Configuration Item: <literal>APT::Get::AutomaticRemove</literal>.
  345. </para></listitem>
  346. </varlistentry>
  347. <varlistentry><term><option>--only-source</option></term>
  348. <listitem><para>Only has meaning for the
  349. <literal>source</literal> and <literal>build-dep</literal>
  350. commands. Indicates that the given source names are not to be
  351. mapped through the binary table. This means that if this option
  352. is specified, these commands will only accept source package
  353. names as arguments, rather than accepting binary package names
  354. and looking up the corresponding source package. Configuration
  355. Item: <literal>APT::Get::Only-Source</literal>.</para></listitem>
  356. </varlistentry>
  357. <varlistentry><term><option>--diff-only</option></term><term><option>--tar-only</option></term>
  358. <listitem><para>Download only the diff or tar file of a source archive.
  359. Configuration Item: <literal>APT::Get::Diff-Only</literal> and
  360. <literal>APT::Get::Tar-Only</literal>.</para></listitem>
  361. </varlistentry>
  362. <varlistentry><term><option>--arch-only</option></term>
  363. <listitem><para>Only process architecture-dependent build-dependencies.
  364. Configuration Item: <literal>APT::Get::Arch-Only</literal>.</para></listitem>
  365. </varlistentry>
  366. <varlistentry><term><option>--allow-unauthenticated</option></term>
  367. <listitem><para>Ignore if packages can't be authenticated and don't prompt about it.
  368. This is usefull for tools like pbuilder.
  369. Configuration Item: <literal>APT::Get::AllowUnauthenticated</literal>.</para></listitem>
  370. </varlistentry>
  371. &apt-commonoptions;
  372. </variablelist>
  373. </refsect1>
  374. <refsect1><title>Files</title>
  375. <variablelist>
  376. <varlistentry><term><filename>/etc/apt/sources.list</filename></term>
  377. <listitem><para>Locations to fetch packages from.
  378. Configuration Item: <literal>Dir::Etc::SourceList</literal>.</para></listitem>
  379. </varlistentry>
  380. <varlistentry><term><filename>/etc/apt/apt.conf</filename></term>
  381. <listitem><para>APT configuration file.
  382. Configuration Item: <literal>Dir::Etc::Main</literal>.</para></listitem>
  383. </varlistentry>
  384. <varlistentry><term><filename>/etc/apt/apt.conf.d/</filename></term>
  385. <listitem><para>APT configuration file fragments
  386. Configuration Item: <literal>Dir::Etc::Parts</literal>.</para></listitem>
  387. </varlistentry>
  388. <varlistentry><term><filename>/etc/apt/preferences</filename></term>
  389. <listitem><para>Version preferences file.
  390. This is where you would specify "pinning",
  391. i.e. a preference to get certain packages
  392. from a separate source
  393. or from a different version of a distribution.
  394. Configuration Item: <literal>Dir::Etc::Preferences</literal>.</para></listitem>
  395. </varlistentry>
  396. <varlistentry><term><filename>&cachedir;/archives/</filename></term>
  397. <listitem><para>Storage area for retrieved package files.
  398. Configuration Item: <literal>Dir::Cache::Archives</literal>.</para></listitem>
  399. </varlistentry>
  400. <varlistentry><term><filename>&cachedir;/archives/partial/</filename></term>
  401. <listitem><para>Storage area for package files in transit.
  402. Configuration Item: <literal>Dir::Cache::Archives</literal> (implicit partial). </para></listitem>
  403. </varlistentry>
  404. <varlistentry><term><filename>&statedir;/lists/</filename></term>
  405. <listitem><para>Storage area for state information for each package resource specified in
  406. &sources-list;
  407. Configuration Item: <literal>Dir::State::Lists</literal>.</para></listitem>
  408. </varlistentry>
  409. <varlistentry><term><filename>&statedir;/lists/partial/</filename></term>
  410. <listitem><para> Storage area for state information in transit.
  411. Configuration Item: <literal>Dir::State::Lists</literal> (implicit partial).</para></listitem>
  412. </varlistentry>
  413. </variablelist>
  414. </refsect1>
  415. <refsect1><title>See Also</title>
  416. <para>&apt-cache;, &apt-cdrom;, &dpkg;, &dselect;, &sources-list;,
  417. &apt-conf;, &apt-config;, &apt-secure;,
  418. The APT User's guide in &guidesdir;, &apt-preferences;, the APT Howto.</para>
  419. </refsect1>
  420. <refsect1><title>Diagnostics</title>
  421. <para><command>apt-get</command> returns zero on normal operation, decimal 100 on error.</para>
  422. </refsect1>
  423. &manbugs;
  424. </refentry>