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diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml new file mode 100644 index 000000000..33269a2f6 --- /dev/null +++ b/doc/apt.conf.5.xml @@ -0,0 +1,389 @@ +<?xml version="1.0" encoding="utf-8" standalone="no"?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [ + +<!ENTITY % aptent SYSTEM "apt.ent"> +%aptent; + +]> + +<refentry> + &apt-docinfo; + + <refmeta> + <refentrytitle>apt.conf</refentrytitle> + <manvolnum>5</manvolnum> + </refmeta> + + <!-- Man page title --> + <refnamediv> + <refname>apt.conf</refname> + <refpurpose>Configuration file for APT</refpurpose> + </refnamediv> + + <refsect1><title>Description</title> + <para><filename>apt.conf</filename> is the main configuration file for the APT suite of + tools, all tools make use of the configuration file and a common command line + parser to provide a uniform environment. When an APT tool starts up it will + read the configuration specified by the <envar>APT_CONFIG</envar> environment + variable (if any) and then read the files in <literal>Dir::Etc::Parts</literal> + then read the main configuration file specified by + <literal>Dir::Etc::main</literal> then finally apply the + command line options to override the configuration directives, possibly + loading even more config files.</para> + + <para>The configuration file is organized in a tree with options organized into + functional groups. option specification is given with a double colon + notation, for instance <literal>APT::Get::Assume-Yes</literal> is an option within + the APT tool group, for the Get tool. options do not inherit from their + parent groups.</para> + + <para>Syntacticly the configuration language is modeled after what the ISC tools + such as bind and dhcp use. Lines starting with + <literal>//</literal> are treated as comments (ignored). + Each line is of the form + <literal>APT::Get::Assume-Yes "true";</literal> The trailing + semicolon is required and the quotes are optional. A new scope can be + opened with curly braces, like:</para> + +<informalexample><programlisting> +APT { + Get { + Assume-Yes "true"; + Fix-Broken "true"; + }; +}; +</programlisting></informalexample> + + <para>with newlines placed to make it more readable. Lists can be created by + opening a scope and including a single word enclosed in quotes followed by a + semicolon. Multiple entries can be included, each separated by a semicolon.</para> + +<informalexample><programlisting> +DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";}; +</programlisting></informalexample> + + <para>In general the sample configuration file in + <filename>&docdir;examples/apt.conf</filename> &configureindex; + is a good guide for how it should look.</para> + + <para>Two specials are allowed, <literal>#include</literal> and <literal>#clear</literal> + <literal>#include</literal> will include the given file, unless the filename + ends in a slash, then the whole directory is included. + <literal>#clear</literal> is used to erase a list of names.</para> + + <para>All of the APT tools take a -o option which allows an arbitrary configuration + directive to be specified on the command line. The syntax is a full option + name (<literal>APT::Get::Assume-Yes</literal> for instance) followed by an equals + sign then the new value of the option. Lists can be appended too by adding + a trailing :: to the list name.</para> + </refsect1> + + <refsect1><title>The APT Group</title> + <para>This group of options controls general APT behavior as well as holding the + options for all of the tools.</para> + + <variablelist> + <varlistentry><term>Architecture</term> + <listitem><para>System Architecture; sets the architecture to use when fetching files and + parsing package lists. The internal default is the architecture apt was + compiled for.</para></listitem> + </varlistentry> + + <varlistentry><term>Ignore-Hold</term> + <listitem><para>Ignore Held packages; This global option causes the problem resolver to + ignore held packages in its decision making.</para></listitem> + </varlistentry> + + <varlistentry><term>Clean-Installed</term> + <listitem><para>Defaults to on. When turned on the autoclean feature will remove any packages + which can no longer be downloaded from the cache. If turned off then + packages that are locally installed are also excluded from cleaning - but + note that APT provides no direct means to reinstall them.</para></listitem> + </varlistentry> + + <varlistentry><term>Immediate-Configure</term> + <listitem><para>Disable Immediate Configuration; This dangerous option disables some + of APT's ordering code to cause it to make fewer dpkg calls. Doing + so may be necessary on some extremely slow single user systems but + is very dangerous and may cause package install scripts to fail or worse. + Use at your own risk.</para></listitem> + </varlistentry> + + <varlistentry><term>Force-LoopBreak</term> + <listitem><para>Never Enable this option unless you -really- know what you are doing. It + permits APT to temporarily remove an essential package to break a + Conflicts/Conflicts or Conflicts/Pre-Depend loop between two essential + packages. SUCH A LOOP SHOULD NEVER EXIST AND IS A GRAVE BUG. This option + will work if the essential packages are not tar, gzip, libc, dpkg, bash or + anything that those packages depend on.</para></listitem> + </varlistentry> + + <varlistentry><term>Cache-Limit</term> + <listitem><para>APT uses a fixed size memory mapped cache file to store the 'available' + information. This sets the size of that cache.</para></listitem> + </varlistentry> + + <varlistentry><term>Build-Essential</term> + <listitem><para>Defines which package(s) are considered essential build dependencies.</para></listitem> + </varlistentry> + + <varlistentry><term>Get</term> + <listitem><para>The Get subsection controls the &apt-get; tool, please see its + documentation for more information about the options here.</para></listitem> + </varlistentry> + + <varlistentry><term>Cache</term> + <listitem><para>The Cache subsection controls the &apt-cache; tool, please see its + documentation for more information about the options here.</para></listitem> + </varlistentry> + + <varlistentry><term>CDROM</term> + <listitem><para>The CDROM subsection controls the &apt-cdrom; tool, please see its + documentation for more information about the options here.</para></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1><title>The Acquire Group</title> + <para>The <literal>Acquire</literal> group of options controls the download of packages + and the URI handlers. + + <variablelist> + <varlistentry><term>Queue-Mode</term> + <listitem><para>Queuing mode; <literal>Queue-Mode</literal> can be one of <literal>host</literal> or + <literal>access</literal> which determines how APT parallelizes outgoing + connections. <literal>host</literal> means that one connection per target host + will be opened, <literal>access</literal> means that one connection per URI type + will be opened.</para></listitem> + </varlistentry> + + <varlistentry><term>Retries</term> + <listitem><para>Number of retries to perform. If this is non-zero APT will retry failed + files the given number of times.</para></listitem> + </varlistentry> + + <varlistentry><term>Source-Symlinks</term> + <listitem><para>Use symlinks for source archives. If set to true then source archives will + be symlinked when possible instead of copying. True is the default.</para></listitem> + </varlistentry> + + <varlistentry><term>http</term> + <listitem><para>HTTP URIs; http::Proxy is the default http proxy to use. It is in the + standard form of <literal>http://[[user][:pass]@]host[:port]/</literal>. Per + host proxies can also be specified by using the form + <literal>http::Proxy::<host></literal> with the special keyword <literal>DIRECT</literal> + meaning to use no proxies. The <envar>http_proxy</envar> environment variable + will override all settings.</para> + + <para>Three settings are provided for cache control with HTTP/1.1 compliant + proxy caches. <literal>No-Cache</literal> tells the proxy to not use its cached + response under any circumstances, <literal>Max-Age</literal> is sent only for + index files and tells the cache to refresh its object if it is older than + the given number of seconds. Debian updates its index files daily so the + default is 1 day. <literal>No-Store</literal> specifies that the cache should never + store this request, it is only set for archive files. This may be useful + to prevent polluting a proxy cache with very large .deb files. Note: + Squid 2.0.2 does not support any of these options.</para> + + <para>The option <literal>timeout</literal> sets the timeout timer used by the method, + this applies to all things including connection timeout and data timeout.</para> + + <para>One setting is provided to control the pipeline depth in cases where the + remote server is not RFC conforming or buggy (such as Squid 2.0.2) + <literal>Acquire::http::Pipeline-Depth</literal> can be a value from 0 to 5 + indicating how many outstanding requests APT should send. A value of + zero MUST be specified if the remote host does not properly linger + on TCP connections - otherwise data corruption will occur. Hosts which + require this are in violation of RFC 2068.</para></listitem> + </varlistentry> + + <varlistentry><term>ftp</term> + <listitem><para>FTP URIs; ftp::Proxy is the default proxy server to use. It is in the + standard form of <literal>ftp://[[user][:pass]@]host[:port]/</literal> and is + overridden by the <envar>ftp_proxy</envar> environment variable. To use a ftp + proxy you will have to set the <literal>ftp::ProxyLogin</literal> script in the + configuration file. This entry specifies the commands to send to tell + the proxy server what to connect to. Please see + &configureindex; for an example of + how to do this. The subsitution variables available are + <literal>$(PROXY_USER)</literal> <literal>$(PROXY_PASS)</literal> <literal>$(SITE_USER)</literal> + <literal>$(SITE_PASS)</literal> <literal>$(SITE)</literal> and <literal>$(SITE_PORT)</literal> + Each is taken from it's respective URI component.</para> + + <para>The option <literal>timeout</literal> sets the timeout timer used by the method, + this applies to all things including connection timeout and data timeout.</para> + + <para>Several settings are provided to control passive mode. Generally it is + safe to leave passive mode on, it works in nearly every environment. + However some situations require that passive mode be disabled and port + mode ftp used instead. This can be done globally, for connections that + go through a proxy or for a specific host (See the sample config file + for examples).</para> + + <para>It is possible to proxy FTP over HTTP by setting the <envar>ftp_proxy</envar> + environment variable to a http url - see the discussion of the http method + above for syntax. You cannot set this in the configuration file and it is + not recommended to use FTP over HTTP due to its low efficiency.</para> + + <para>The setting <literal>ForceExtended</literal> controls the use of RFC2428 + <literal>EPSV</literal> and <literal>EPRT</literal> commands. The defaut is false, which means + these commands are only used if the control connection is IPv6. Setting this + to true forces their use even on IPv4 connections. Note that most FTP servers + do not support RFC2428.</para></listitem> + </varlistentry> + + <varlistentry><term>cdrom</term> + <listitem><para>CDROM URIs; the only setting for CDROM URIs is the mount point, + <literal>cdrom::Mount</literal> which must be the mount point for the CDROM drive + as specified in <filename>/etc/fstab</filename>. It is possible to provide + alternate mount and unmount commands if your mount point cannot be listed + in the fstab (such as an SMB mount and old mount packages). The syntax + is to put <literallayout>"/cdrom/"::Mount "foo";</literallayout> within + the cdrom block. It is important to have the trailing slash. Unmount + commands can be specified using UMount.</para></listitem> + </varlistentry> + </variablelist> + </para> + </refsect1> + + <refsect1><title>Directories</title> + + <para>The <literal>Dir::State</literal> section has directories that pertain to local + state information. <literal>lists</literal> is the directory to place downloaded + package lists in and <literal>status</literal> is the name of the dpkg status file. + <literal>preferences</literal> is the name of the APT preferences file. + <literal>Dir::State</literal> contains the default directory to prefix on all sub + items if they do not start with <filename>/</filename> or <filename>./</filename>.</para> + + <para><literal>Dir::Cache</literal> contains locations pertaining to local cache + information, such as the two package caches <literal>srcpkgcache</literal> and + <literal>pkgcache</literal> as well as the location to place downloaded archives, + <literal>Dir::Cache::archives</literal>. Generation of caches can be turned off + by setting their names to be blank. This will slow down startup but + save disk space. It is probably prefered to turn off the pkgcache rather + than the srcpkgcache. Like <literal>Dir::State</literal> the default + directory is contained in <literal>Dir::Cache</literal></para> + + <para><literal>Dir::Etc</literal> contains the location of configuration files, + <literal>sourcelist</literal> gives the location of the sourcelist and + <literal>main</literal> is the default configuration file (setting has no effect, + unless it is done from the config file specified by + <envar>APT_CONFIG</envar>.</para> + + <para>The <literal>Dir::Parts</literal> setting reads in all the config fragments in + lexical order from the directory specified. After this is done then the + main config file is loaded.</para> + + <para>Binary programs are pointed to by <literal>Dir::Bin</literal>. <literal>Dir::Bin::Methods</literal> + specifies the location of the method handlers and <literal>gzip</literal>, + <literal>dpkg</literal>, <literal>apt-get</literal> <literal>dpkg-source</literal> + <literal>dpkg-buildpackage</literal> and <literal>apt-cache</literal> specify the location + of the respective programs.</para> + </refsect1> + + <refsect1><title>APT in DSelect</title> + <para> + When APT is used as a &dselect; method several configuration directives + control the default behaviour. These are in the <literal>DSelect</literal> section.</para> + + <variablelist> + <varlistentry><term>Clean</term> + <listitem><para>Cache Clean mode; this value may be one of always, prompt, auto, + pre-auto and never. always and prompt will remove all packages from + the cache after upgrading, prompt (the default) does so conditionally. + auto removes only those packages which are no longer downloadable + (replaced with a new version for instance). pre-auto performs this + action before downloading new packages.</para></listitem> + </varlistentry> + + <varlistentry><term>options</term> + <listitem><para>The contents of this variable is passed to &apt-get; as command line + options when it is run for the install phase.</para></listitem> + </varlistentry> + + <varlistentry><term>Updateoptions</term> + <listitem><para>The contents of this variable is passed to &apt-get; as command line + options when it is run for the update phase.</para></listitem> + </varlistentry> + + <varlistentry><term>PromptAfterUpdate</term> + <listitem><para>If true the [U]pdate operation in &dselect; will always prompt to continue. + The default is to prompt only on error.</para></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1><title>How APT calls dpkg</title> + <para>Several configuration directives control how APT invokes &dpkg;. These are + in the <literal>DPkg</literal> section.</para> + + <variablelist> + <varlistentry><term>options</term> + <listitem><para>This is a list of options to pass to dpkg. The options must be specified + using the list notation and each list item is passed as a single argument + to &dpkg;.</para></listitem> + </varlistentry> + + <varlistentry><term>Pre-Invoke</term><term>Post-Invoke</term> + <listitem><para>This is a list of shell commands to run before/after invoking &dpkg;. + Like <literal>options</literal> this must be specified in list notation. The + commands are invoked in order using <filename>/bin/sh</filename>, should any + fail APT will abort.</para></listitem> + </varlistentry> + + <varlistentry><term>Pre-Install-Pkgs</term> + <listitem><para>This is a list of shell commands to run before invoking dpkg. Like + <literal>options</literal> this must be specified in list notation. The commands + are invoked in order using <filename>/bin/sh</filename>, should any fail APT + will abort. APT will pass to the commands on standard input the + filenames of all .deb files it is going to install, one per line.</para> + + <para>Version 2 of this protocol dumps more information, including the + protocol version, the APT configuration space and the packages, files + and versions being changed. Version 2 is enabled by setting + <literal>DPkg::Tools::options::cmd::Version</literal> to 2. <literal>cmd</literal> is a + command given to <literal>Pre-Install-Pkgs</literal>.</para></listitem> + </varlistentry> + + <varlistentry><term>Run-Directory</term> + <listitem><para>APT chdirs to this directory before invoking dpkg, the default is + <filename>/</filename>.</para></listitem> + </varlistentry> + + <varlistentry><term>Build-options</term> + <listitem><para>These options are passed to &dpkg-buildpackage; when compiling packages, + the default is to disable signing and produce all binaries.</para></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1><title>Debug options</title> + <para>Most of the options in the <literal>debug</literal> section are not interesting to + the normal user, however <literal>Debug::pkgProblemResolver</literal> shows + interesting output about the decisions dist-upgrade makes. + <literal>Debug::NoLocking</literal> disables file locking so APT can do some + operations as non-root and <literal>Debug::pkgDPkgPM</literal> will print out the + command line for each dpkg invokation. <literal>Debug::IdentCdrom</literal> will + disable the inclusion of statfs data in CDROM IDs.</para> + </refsect1> + + <refsect1><title>Examples</title> + <para>&configureindex; contains a + sample configuration file showing the default values for all possible + options.</para> + </refsect1> + + <refsect1><title>Files</title> + <para><filename>/etc/apt/apt.conf</filename></para> + </refsect1> + + <refsect1><title>See Also</title> + <para>&apt-cache;, &apt-config;<!-- ? reading apt.conf -->, &apt-preferences;.</para> + </refsect1> + + &manbugs; + &manauthor; + +</refentry> + |