merged typo fixes from david

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

diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml
index ce7012460cd67690d860fb8749fe2f8f17a160ae..e752f9d27436beba8e88c8b430cceb774bdb05e0 100644 (file)
--- a/doc/apt.conf.5.xml
+++ b/doc/apt.conf.5.xml
@@ -12,15 +12,22 @@
  <refentryinfo>
    &apt-author.jgunthorpe;
    &apt-author.team;
  <refentryinfo>
    &apt-author.jgunthorpe;
    &apt-author.team;

+   <author>
+     <firstname>Daniel</firstname>
+     <surname>Burrows</surname>
+     <contrib>Initial documentation of Debug::*.</contrib>
+     <email>dburrows@debian.org</email>
+   </author>

    &apt-email;
    &apt-product;
    <!-- The last update date -->
    &apt-email;
    &apt-product;
    <!-- The last update date -->

-   <date>29 February 2004</date>
+   <date>18 September 2009</date>

  </refentryinfo>
  
  <refmeta>
    <refentrytitle>apt.conf</refentrytitle>
    <manvolnum>5</manvolnum>
  </refentryinfo>
  
  <refmeta>
    <refentrytitle>apt.conf</refentrytitle>
    <manvolnum>5</manvolnum>

+   <refmiscinfo class="manual">APT</refmiscinfo>

  </refmeta>
  
  <!-- Man page title -->
  </refmeta>
  
  <!-- Man page title -->


@@ -47,8 +54,9 @@
    parent groups.</para> 
 
    <para>Syntactically the configuration language is modeled after what the ISC tools
    parent groups.</para> 
 
    <para>Syntactically 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).
+   such as bind and dhcp use. Lines starting with
+   <literal>//</literal> are treated as comments (ignored), as well as all text
+   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
    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


@@ -64,7 +72,7 @@ APT {
 </programlisting></informalexample>
 
    <para>with newlines placed to make it more readable. Lists can be created by 
 </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 
+   opening a scope and including a single string enclosed in quotes followed by a

    semicolon. Multiple entries can be included, each separated by a semicolon.</para>
 
 <informalexample><programlisting>   
    semicolon. Multiple entries can be included, each separated by a semicolon.</para>
 
 <informalexample><programlisting>   


@@ -78,16 +86,40 @@ 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> 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>#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>
+   <literal>#clear</literal> is used to erase a part of the configuration tree. The
+   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>


@@ -103,7 +135,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      
      <varlistentry><term>Default-Release</term>
         <listitem><para>Default release to install packages from if more than one
      
      <varlistentry><term>Default-Release</term>
         <listitem><para>Default release to install packages from if more than one

-        version available. Contains release name or release version. Examples: 'stable', 'testing', 'unstable', '4.0', '5.0*'. Release codenames ('etch', 'lenny' etc.) are not allowed now. See also &apt-preferences;.</para></listitem>
+        version available. Contains release name, codename or release version. Examples: 'stable', 'testing', 'unstable', 'lenny', 'squeeze', '4.0', '5.0*'. See also &apt-preferences;.</para></listitem>

      </varlistentry>
      
      <varlistentry><term>Ignore-Hold</term>
      </varlistentry>
      
      <varlistentry><term>Ignore-Hold</term>


@@ -167,7 +199,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
 
    <variablelist>
      <varlistentry><term>PDiffs</term>
 
    <variablelist>
      <varlistentry><term>PDiffs</term>

-        <listitem><para>Try do download deltas called <literal>PDiffs</literal> for
+        <listitem><para>Try to download deltas called <literal>PDiffs</literal> for

         Packages or Sources files instead of downloading whole ones. True
         by default.</para></listitem>
      </varlistentry>
         Packages or Sources files instead of downloading whole ones. True
         by default.</para></listitem>
      </varlistentry>


@@ -195,8 +227,9 @@ 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 


@@ -217,13 +250,45 @@ 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>
 

+     <varlistentry><term>https</term>
+        <listitem><para>HTTPS URIs. Cache-control and proxy options are the same as for
+        <literal>http</literal> method.
+        <literal>Pipeline-Depth</literal> option is not supported yet.</para>
+
+        <para><literal>CaInfo</literal> suboption specifies place of file that
+        holds info about trusted certificates.
+        <literal>&lt;host&gt;::CaInfo</literal> is corresponding per-host option.
+        <literal>Verify-Peer</literal> boolean suboption determines whether verify
+        server's host certificate against trusted certificates or not.
+        <literal>&lt;host&gt;::Verify-Peer</literal> is corresponding per-host option.
+        <literal>Verify-Host</literal> boolean suboption determines whether verify
+        server's hostname or not.
+        <literal>&lt;host&gt;::Verify-Host</literal> is corresponding per-host option.
+        <literal>SslCert</literal> determines what certificate to use for client
+        authentication. <literal>&lt;host&gt;::SslCert</literal> is corresponding per-host option.
+        <literal>SslKey</literal> determines what private key to use for client
+        authentication. <literal>&lt;host&gt;::SslKey</literal> is corresponding per-host option.
+        <literal>SslForceVersion</literal> overrides default SSL version to use.
+        Can contain 'TLSv1' or 'SSLv3' string.
+        <literal>&lt;host&gt;::SslForceVersion</literal> is corresponding per-host option.
+        </para></listitem></varlistentry>
+

      <varlistentry><term>ftp</term>
      <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 


@@ -272,6 +337,34 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
      </para></listitem>
      </varlistentry>
 
      </para></listitem>
      </varlistentry>
 

+     <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.
+     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>
+     </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
+     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>
  </refsect1>
    </variablelist>
   </para>
  </refsect1>


@@ -306,6 +399,7 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
 
    <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>, 
 
    <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>bzip2</literal>, <literal>lzma</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>
    <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>


@@ -398,19 +492,472 @@ 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><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.
-   <literal>Debug::Acquire::gpgv</literal> Debugging of the gpgv method.
+ <refsect1>
+   <title>Periodic and Archives options</title>
+   <para><literal>APT::Periodic</literal> and <literal>APT::Archives</literal>
+   groups of options configure behavior of apt periodic updates, which is
+   done by <literal>/etc/cron.daily/apt</literal> script. See header of
+   this script for the brief documentation of these options.

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

+
+ <refsect1>
+   <title>Debug options</title>
+   <para>
+     Enabling options in the <literal>Debug::</literal> section will
+     cause debugging information to be sent to the standard error
+     stream of the program utilizing the <literal>apt</literal>
+     libraries, or enable special program modes that are primarily
+     useful for debugging the behavior of <literal>apt</literal>.
+     Most of these options are not interesting to a normal user, but a
+     few may be:
+
+     <itemizedlist>
+       <listitem>
+        <para>
+          <literal>Debug::pkgProblemResolver</literal> enables output
+          about the decisions made by
+          <literal>dist-upgrade, upgrade, install, remove, purge</literal>.
+        </para>
+       </listitem>
+
+       <listitem>
+        <para>
+          <literal>Debug::NoLocking</literal> disables all file
+          locking.  This can be used to run some operations (for
+          instance, <literal>apt-get -s install</literal>) as a
+          non-root user.
+        </para>
+       </listitem>
+
+       <listitem>
+        <para>
+          <literal>Debug::pkgDPkgPM</literal> prints out the actual
+          command line each time that <literal>apt</literal> invokes
+          &dpkg;.
+        </para>
+       </listitem>
+
+       <listitem>
+        <para>
+          <literal>Debug::IdentCdrom</literal> disables the inclusion
+          of statfs data in CDROM IDs.  <!-- TODO: provide a
+          motivating example, except I haven't a clue why you'd want
+          to do this. -->
+        </para>
+       </listitem>
+     </itemizedlist>
+   </para>
+
+   <para>
+     A full list of debugging options to apt follows.
+   </para>
+
+   <variablelist>
+     <varlistentry>
+       <term><literal>Debug::Acquire::cdrom</literal></term>
+
+       <listitem>
+        <para>
+          Print information related to accessing
+          <literal>cdrom://</literal> sources.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::Acquire::ftp</literal></term>
+
+       <listitem>
+        <para>
+          Print information related to downloading packages using
+          FTP.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::Acquire::http</literal></term>
+
+       <listitem>
+        <para>
+          Print information related to downloading packages using
+          HTTP.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::Acquire::https</literal></term>
+
+       <listitem>
+        <para>
+          Print information related to downloading packages using
+          HTTPS.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::Acquire::gpgv</literal></term>
+
+       <listitem>
+        <para>
+          Print information related to verifying cryptographic
+          signatures using <literal>gpg</literal>.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::aptcdrom</literal></term>
+
+       <listitem>
+        <para>
+          Output information about the process of accessing
+          collections of packages stored on CD-ROMs.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::BuildDeps</literal></term>
+       <listitem>
+        <para>
+          Describes the process of resolving build-dependencies in
+          &apt-get;.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::Hashes</literal></term>
+       <listitem>
+        <para>
+          Output each cryptographic hash that is generated by the
+          <literal>apt</literal> libraries.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::IdentCDROM</literal></term>
+       <listitem>
+        <para>
+          Do not include information from <literal>statfs</literal>,
+          namely the number of used and free blocks on the CD-ROM
+          filesystem, when generating an ID for a CD-ROM.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::NoLocking</literal></term>
+       <listitem>
+        <para>
+          Disable all file locking.  For instance, this will allow
+          two instances of <quote><literal>apt-get
+          update</literal></quote> to run at the same time.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAcquire</literal></term>
+
+       <listitem>
+        <para>
+          Log when items are added to or removed from the global
+          download queue.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAcquire::Auth</literal></term>
+       <listitem>
+        <para>
+          Output status messages and errors related to verifying
+          checksums and cryptographic signatures of downloaded files.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAcquire::Diffs</literal></term>
+       <listitem>
+        <para>
+          Output information about downloading and applying package
+          index list diffs, and errors relating to package index list
+          diffs.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAcquire::RRed</literal></term>
+
+       <listitem>
+        <para>
+          Output information related to patching apt package lists
+          when downloading index diffs instead of full indices.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAcquire::Worker</literal></term>
+
+       <listitem>
+        <para>
+          Log all interactions with the sub-processes that actually
+          perform downloads.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgAutoRemove</literal></term>
+
+       <listitem>
+        <para>
+          Log events related to the automatically-installed status of
+          packages and to the removal of unused packages.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgDepCache::AutoInstall</literal></term>
+       <listitem>
+        <para>
+          Generate debug messages describing which packages are being
+          automatically installed to resolve dependencies.  This
+          corresponds to the initial auto-install pass performed in,
+          e.g., <literal>apt-get install</literal>, and not to the
+          full <literal>apt</literal> dependency resolver; see
+          <literal>Debug::pkgProblemResolver</literal> for that.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgDepCache::Marker</literal></term>
+       <listitem>
+        <para>
+           Generate debug messages describing which package is marked
+          as keep/install/remove while the ProblemResolver does his work.
+          Each addition or deletion may trigger additional actions;
+          they are shown indented two additional space under the original entry.
+          The format for each line is <literal>MarkKeep</literal>,
+          <literal>MarkDelete</literal> or <literal>MarkInstall</literal> followed by
+          <literal>package-name &lt;a.b.c -&gt; d.e.f | x.y.z&gt; (section)</literal>
+          where <literal>a.b.c</literal> is the current version of the package,
+          <literal>d.e.f</literal> is the version considered for installation and
+          <literal>x.y.z</literal> is a newer version, but not considered for installation
+          (because of a low pin score). The later two can be omitted if there is none or if
+          it is the same version as the installed.
+          <literal>section</literal> is the name of the section the package appears in.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <!-- Question: why doesn't this do anything?  The code says it should. -->
+     <varlistentry>
+       <term><literal>Debug::pkgInitConfig</literal></term>
+       <listitem>
+        <para>
+          Dump the default configuration to standard error on
+          startup.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgDPkgPM</literal></term>
+       <listitem>
+        <para>
+          When invoking &dpkg;, output the precise command line with
+          which it is being invoked, with arguments separated by a
+          single space character.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgDPkgProgressReporting</literal></term>
+       <listitem>
+        <para>
+          Output all the data received from &dpkg; on the status file
+          descriptor and any errors encountered while parsing it.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgOrderList</literal></term>
+
+       <listitem>
+        <para>
+          Generate a trace of the algorithm that decides the order in
+          which <literal>apt</literal> should pass packages to
+          &dpkg;.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgPackageManager</literal></term>
+
+       <listitem>
+        <para>
+          Output status messages tracing the steps performed when
+          invoking &dpkg;.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgPolicy</literal></term>
+
+       <listitem>
+        <para>
+          Output the priority of each package list on startup.
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgProblemResolver</literal></term>
+
+       <listitem>
+        <para>
+          Trace the execution of the dependency resolver (this
+          applies only to what happens when a complex dependency
+          problem is encountered).
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::pkgProblemResolver::ShowScores</literal></term>
+       <listitem>
+        <para>
+          Display a list of all installed packages with their calculated score
+          used by the pkgProblemResolver. The description of the package
+          is the same as described in <literal>Debug::pkgDepCache::Marker</literal>
+        </para>
+       </listitem>
+     </varlistentry>
+
+     <varlistentry>
+       <term><literal>Debug::sourceList</literal></term>
+
+       <listitem>
+        <para>
+          Print information about the vendors read from
+          <filename>/etc/apt/vendors.list</filename>.
+        </para>
+       </listitem>
+     </varlistentry>
+
+<!-- 2009/07/11 Currently used nowhere. The corresponding code
+is commented.
+     <varlistentry>
+       <term><literal>Debug::Vendor</literal></term>
+
+       <listitem>
+        <para>
+          Print information about each vendor.
+        </para>
+       </listitem>
+     </varlistentry>
+-->
+   </variablelist>
+ </refsect1>

  
  <refsect1><title>Examples</title>
    <para>&configureindex; is a 
  
  <refsect1><title>Examples</title>
    <para>&configureindex; is a 


@@ -419,7 +966,9 @@ DPkg::Pre-Install-Pkgs {"/usr/sbin/dpkg-preconfigure --apt";};
  </refsect1>
  
  <refsect1><title>Files</title>
  </refsect1>
  
  <refsect1><title>Files</title>

-   <para><filename>/etc/apt/apt.conf</filename></para>
+   <variablelist>
+      &file-aptconf;
+   </variablelist>

  </refsect1>
  
  <refsect1><title>See Also</title>
  </refsect1>
  
  <refsect1><title>See Also</title>