* merge lp:~mvo/apt/netrc branch, this adds support for a

[apt.git] / doc / apt.conf.5.xml

diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml
index 2412260e7cb51b189165355f019b21b24327a5c5..a1252432800aff2c3030d9fb4073947ea9de8aad 100644 (file)
--- a/doc/apt.conf.5.xml
+++ b/doc/apt.conf.5.xml
@@ -21,7 +21,7 @@
    &apt-email;
    &apt-product;
    <!-- The last update date -->
    &apt-email;
    &apt-product;
    <!-- The last update date -->

-   <date>10 December 2008</date>
+   <date>18 September 2009</date>

  </refentryinfo>
  
  <refmeta>
  </refentryinfo>
  
  <refmeta>


@@ -59,8 +59,12 @@
    between <literal>/*</literal> and <literal>*/</literal>, just like C/C++ comments.
    Each line is of the form
    <literal>APT::Get::Assume-Yes "true";</literal> The trailing 
    between <literal>/*</literal> and <literal>*/</literal>, just like C/C++ comments.
    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>
+   semicolon and the quotes are required. The value must be on one line, and
+   there is no kind of string concatenation. It must not include inside quotes.
+   The behavior of the backslash "\" and escaped characters inside a value is
+   undefined and it should not be used. An option name may include
+   alphanumerical characters and the "/-:._+" characters. A new scope can
+   be opened with curly braces, like:</para>

 
 <informalexample><programlisting>   
 APT {
 
 <informalexample><programlisting>   
 APT {


@@ -86,17 +90,41 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
    <para>The names of the configuration items are not case-sensitive. So in the previous example
    you could use <literal>dpkg::pre-install-pkgs</literal>.</para>
 
    <para>The names of the configuration items are not case-sensitive. So in the previous example
    you could use <literal>dpkg::pre-install-pkgs</literal>.</para>
 

-   <para>Two specials are allowed, <literal>#include</literal> and <literal>#clear</literal> 
+   <para>Names for the configuration items are optional if a list is defined as it can be see in
+   the <literal>DPkg::Pre-Install-Pkgs</literal> example above. If you don't specify a name a
+   new entry will simply add a new option to the list. If you specify a name you can override
+   the option as every other option by reassigning a new value to the option.</para>
+
+   <para>Two specials are allowed, <literal>#include</literal> (which is deprecated
+   and not supported by alternative implementations) 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 part of the configuration tree. The
    <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 part of the configuration tree. The

-   specified element and all its descendents are erased.</para>
+   specified element and all its descendants are erased.
+   (Note that these lines also need to end with a semicolon.)</para>
+
+   <para>The #clear command is the only way to delete a list or a complete scope.
+   Reopening a scope or the ::-style described below will <emphasis>not</emphasis>
+   override previously written entries. Only options can be overridden by addressing a new
+   value to it - lists and scopes can't be overridden, only cleared.</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 
 
    <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>
+   a trailing :: to the list name. (As you might suspect: The scope syntax can't be used
+   on the command line.)</para>
+
+   <para>Note that you can use :: only for appending one item per line to a list and
+   that you should not use it in combination with the scope syntax.
+   (The scope syntax implicit insert ::) Using both syntaxes together will trigger a bug
+   which some users unfortunately relay on: An option with the unusual name "<literal>::</literal>"
+   which acts like every other option with a name. These introduces many problems
+   including that a user who writes multiple lines in this <emphasis>wrong</emphasis> syntax in
+   the hope to append to a list will gain the opposite as only the last assignment for this option
+   "<literal>::</literal>" will be used. Upcoming APT versions will raise errors and
+   will stop working if they encounter this misuse, so please correct such statements now
+   as long as APT doesn't complain explicit about them.</para>

  </refsect1>
 
  <refsect1><title>The APT Group</title>
  </refsect1>
 
  <refsect1><title>The APT Group</title>


@@ -204,8 +232,9 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      standard form of <literal>http://[[user][:pass]@]host[:port]/</literal>. Per 
      host proxies can also be specified by using the form 
      <literal>http::Proxy::&lt;host&gt;</literal> with the special keyword <literal>DIRECT</literal> 
      standard form of <literal>http://[[user][:pass]@]host[:port]/</literal>. Per 
      host proxies can also be specified by using the form 
      <literal>http::Proxy::&lt;host&gt;</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>
+        meaning to use no proxies. If no one of the above settings is specified,
+        <envar>http_proxy</envar> environment variable
+        will be used.</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 
 
      <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 


@@ -226,7 +255,12 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      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
      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>
+     require this are in violation of RFC 2068.</para>
+
+     <para>The used bandwidth can be limited with <literal>Acquire::http::Dl-Limit</literal>
+     which accepts integer values in kilobyte. The default value is 0 which deactivates
+     the limit and tries uses as much as possible of the bandwidth (Note that this option implicit
+     deactivates the download from multiple servers at the same time.)</para></listitem>

      </varlistentry>
 
      <varlistentry><term>https</term>
      </varlistentry>
 
      <varlistentry><term>https</term>


@@ -253,9 +287,13 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
         </para></listitem></varlistentry>
 
      <varlistentry><term>ftp</term>
         </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 
+     <listitem><para>FTP URIs; ftp::Proxy is the default ftp proxy to use. It is in the 
+     standard form of <literal>ftp://[[user][:pass]@]host[:port]/</literal>. Per 
+     host proxies can also be specified by using the form 
+     <literal>ftp::Proxy::&lt;host&gt;</literal> with the special keyword <literal>DIRECT</literal> 
+        meaning to use no proxies. If no one of the above settings is specified,
+        <envar>ftp_proxy</envar> environment variable
+        will be used. 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 
      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 


@@ -293,7 +331,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      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 
      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 
+     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>
      the cdrom block. It is important to have the trailing slash. Unmount 
      commands can be specified using UMount.</para></listitem>
      </varlistentry>


@@ -307,16 +345,30 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      <varlistentry><term>CompressionTypes</term>
      <listitem><para>List of compression types which are understood by the acquire methods.
      Files like <filename>Packages</filename> can be available in various compression formats.
      <varlistentry><term>CompressionTypes</term>
      <listitem><para>List of compression types which are understood by the acquire methods.
      Files like <filename>Packages</filename> can be available in various compression formats.

-     This list defines in which order the acquire methods will try to download these files.
-     Per default <command>bzip2</command> compressed files will be prefered over
-     <command>lzma</command>, <command>gzip</command> and uncompressed files. The syntax for
-     the configuration fileentry is
+     Per default the acquire methods can decompress <command>bzip2</command>, <command>lzma</command>
+     and <command>gzip</command> compressed files, with this setting more formats can be added
+     on the fly or the used method can be changed. The syntax for this is:

      <synopsis>Acquire::CompressionTypes::<replaceable>FileExtension</replaceable> "<replaceable>Methodname</replaceable>";</synopsis>
      <synopsis>Acquire::CompressionTypes::<replaceable>FileExtension</replaceable> "<replaceable>Methodname</replaceable>";</synopsis>

-     e.g. <synopsis>Acquire::CompressionTypes::bz2 "bzip2";</synopsis>
-     Note that at runtime the <literal>Dir::Bin::<replaceable>Methodname</replaceable></literal> will
+     </para><para>Also the <literal>Order</literal> subgroup can be used to define in which order
+     the acquire system will try to download the compressed files. The acquire system will try the first
+     and proceed with the next compression type in this list on error, so to prefer one over the other type
+     simple add the preferred type at first - not already added default types will be added at run time
+     to the end of the list, so e.g. <synopsis>Acquire::CompressionTypes::Order:: "gz";</synopsis> can
+     be used to prefer <command>gzip</command> compressed files over <command>bzip2</command> and <command>lzma</command>.
+     If <command>lzma</command> should be preferred over <command>gzip</command> and <command>bzip2</command> the
+     configure setting should look like this <synopsis>Acquire::CompressionTypes::Order { "lzma"; "gz"; };</synopsis>
+     It is not needed to add <literal>bz2</literal> explicit to the list as it will be added automatic.</para>
+     <para>Note that at run time the <literal>Dir::Bin::<replaceable>Methodname</replaceable></literal> will

      be checked: If this setting exists the method will only be used if this file exists, e.g. for
      be checked: If this setting exists the method will only be used if this file exists, e.g. for

-     the bzip2 method above (the inbuilt) setting is <literallayout>Dir::Bin::bzip2 "/bin/bzip2";</literallayout>
-     </para></listitem>
+     the bzip2 method (the inbuilt) setting is <literallayout>Dir::Bin::bzip2 "/bin/bzip2";</literallayout>
+     Note also that list entries specified on the command line will be added at the end of the list
+     specified in the configuration files, but before the default entries. To prefer a type in this case
+     over the ones specified in in the configuration files you can set the option direct - not in list style.
+     This will not override the defined list, it will only prefix the list with this type.</para>
+     <para>While it is possible to add an empty compression type to the order list, but APT in its current
+     version doesn't understand it correctly and will display many warnings about not downloaded files -
+     these warnings are most of the time false negatives. Future versions will maybe include a way to
+     really prefer uncompressed files to support the usage of local mirrors.</para></listitem>

      </varlistentry>
    </variablelist>
   </para>
      </varlistentry>
    </variablelist>
   </para>


@@ -445,6 +497,87 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      the default is to disable signing and produce all binaries.</para></listitem>
      </varlistentry>
    </variablelist>
      the default is to disable signing and produce all binaries.</para></listitem>
      </varlistentry>
    </variablelist>

+
+   <refsect2><title>dpkg trigger usage (and related options)</title>
+     <para>APT can call dpkg in a way so it can make aggressive use of triggers over
+     multiply calls of dpkg. Without further options dpkg will use triggers only in between his
+     own run. Activating these options can therefore decrease the time needed to perform the
+     install / upgrade. Note that it is intended to activate these options per default in the
+     future, but as it changes the way APT calling dpkg drastically it needs a lot more testing.
+     <emphasis>These options are therefore currently experimental and should not be used in
+     productive environments.</emphasis> Also it breaks the progress reporting so all frontends will
+     currently stay around half (or more) of the time in the 100% state while it actually configures
+     all packages.</para>
+     <para>Note that it is not guaranteed that APT will support these options or that these options will
+     not cause (big) trouble in the future. If you have understand the current risks and problems with
+     these options, but are brave enough to help testing them create a new configuration file and test a
+     combination of options. Please report any bugs, problems and improvements you encounter and make sure
+     to note which options you have used in your reports. Asking dpkg for help could also be useful for
+     debugging proposes, see e.g. <command>dpkg --audit</command>. A defensive option combination would be
+<literallayout>DPkg::NoTriggers "true";
+PackageManager::Configure "smart";
+DPkg::ConfigurePending "true";
+DPkg::TriggersPending "true";</literallayout></para>
+
+     <variablelist>
+       <varlistentry><term>DPkg::NoTriggers</term>
+       <listitem><para>Add the no triggers flag to all dpkg calls (expect the ConfigurePending call).
+       See &dpkg; if you are interested in what this actually means. In short: dpkg will not run the
+       triggers then this flag is present unless it is explicit called to do so in an extra call.
+       Note that this option exists (undocumented) also in older apt versions with a slightly different
+       meaning: Previously these option only append --no-triggers to the configure calls to dpkg -
+       now apt will add these flag also to the unpack and remove calls.</para></listitem>
+       </varlistentry>
+       <varlistentry><term>PackageManager::Configure</term>
+       <listitem><para>Valid values are "<literal>all</literal>", "<literal>smart</literal>" and "<literal>no</literal>".
+       "<literal>all</literal>" is the default value and causes APT to configure all packages explicit.
+       The "<literal>smart</literal>" way is it to configure only packages which need to be configured before
+       another package can be unpacked (Pre-Depends) and let the rest configure by dpkg with a call generated
+       by the next option. "<literal>no</literal>" on the other hand will not configure anything and totally
+       relay on dpkg for configuration (which will at the moment fail if a Pre-Depends is encountered).
+       Setting this option to another than the all value will implicit activate also the next option per
+       default as otherwise the system could end in an unconfigured status which could be unbootable!
+       </para></listitem>
+       </varlistentry>
+       <varlistentry><term>DPkg::ConfigurePending</term>
+       <listitem><para>If this option is set apt will call <command>dpkg --configure --pending</command>
+       to let dpkg handle all required configurations and triggers. This option is activated automatic
+       per default if the previous option is not set to <literal>all</literal>, but deactivating could be useful
+       if you want to run APT multiple times in a row - e.g. in an installer. In this sceneries you could
+       deactivate this option in all but the last run.</para></listitem>
+       </varlistentry>
+       <varlistentry><term>DPkg::TriggersPending</term>
+       <listitem><para>Useful for <literal>smart</literal> configuration as a package which has pending
+       triggers is not considered as <literal>installed</literal> and dpkg treats them as <literal>unpacked</literal>
+       currently which is a dealbreaker for Pre-Dependencies (see debbugs #526774). Note that this will
+       process all triggers, not only the triggers needed to configure this package.</para></listitem>
+       </varlistentry>
+       <varlistentry><term>PackageManager::UnpackAll</term>
+       <listitem><para>As the configuration can be deferred to be done at the end by dpkg it can be
+       tried to order the unpack series only by critical needs, e.g. by Pre-Depends. Default is true
+       and therefore the "old" method of ordering in various steps by everything. While both method
+       were present in earlier APT versions the <literal>OrderCritical</literal> method was unused, so
+       this method is very experimental and needs further improvements before becoming really useful.
+       </para></listitem>
+       </varlistentry>
+       <varlistentry><term>OrderList::Score::Immediate</term>
+       <listitem><para>Essential packages (and there dependencies) should be configured immediately
+       after unpacking. It will be a good idea to do this quite early in the upgrade process as these
+       these configure calls require currently also <literal>DPkg::TriggersPending</literal> which
+       will run quite a few triggers (which maybe not needed). Essentials get per default a high score
+       but the immediate flag is relatively low (a package which has a Pre-Depends is higher rated).
+       These option and the others in the same group can be used to change the scoring. The following
+       example shows the settings with there default values.
+       <literallayout>OrderList::Score {
+       Delete 500;
+       Essential 200;
+       Immediate 10;
+       PreDepends 50;
+};</literallayout>
+       </para></listitem>
+       </varlistentry>
+     </variablelist>
+   </refsect2>

  </refsect1>
 
  <refsect1>
  </refsect1>
 
  <refsect1>


@@ -839,15 +972,7 @@ is commented.
  
  <refsect1><title>Files</title>
    <variablelist>
  
  <refsect1><title>Files</title>
    <variablelist>

-      <varlistentry><term><filename>/etc/apt/apt.conf</filename></term>
-      <listitem><para>APT configuration file.
-      Configuration Item: <literal>Dir::Etc::Main</literal>.</para></listitem> 
-      </varlistentry>
-
-      <varlistentry><term><filename>/etc/apt/apt.conf.d/</filename></term>
-      <listitem><para>APT configuration file fragments.
-      Configuration Item: <literal>Dir::Etc::Parts</literal>.</para></listitem>
-      </varlistentry>
+      &file-aptconf;

    </variablelist>
  </refsect1>
  
    </variablelist>
  </refsect1>