configuration list - in which case it will be silently ignored.</para></listitem>
<listitem><para>the main configuration file specified by
<literal>Dir::Etc::main</literal></para></listitem>
+ <listitem><para>all options set in the binary specific configuration
+ subtree are moved into the root of the tree.</para></listitem>
<listitem><para>the command line options are applied to override the
configuration directives or to load even more configuration files.</para></listitem>
</orderedlist>
<literal>Valid-Until</literal> header, but if they don't or a
stricter value is desired the <literal>Max-ValidTime</literal>
option below can be used.
+ The <option>Check-Valid-Until</option> option of &sources-list; entries should be
+ preferred to disable the check selectively instead of using this global override.
</para></listitem>
</varlistentry>
the earlier date of the two is used as the expiration date.
The default value is <literal>0</literal> which stands for "valid forever".
Archive specific settings can be made by appending the label of the archive
- to the option name.
+ to the option name. Preferably, the same can be achieved for specific
+ &sources-list; entries by using the <option>Valid-Until-Max</option> option there.
</para></listitem>
</varlistentry>
frequently updated archive with a <literal>Valid-Until</literal> header
instead of completely disabling the expiration date checking.
Archive specific settings can and should be used by appending the label of
- the archive to the option name.
+ the archive to the option name. Preferably, the same can be achieved for specific
+ &sources-list; entries by using the <option>Valid-Until-Min</option> option there.
</para></listitem>
</varlistentry>
<varlistentry><term><option>PDiffs</option></term>
<listitem><para>Try to download deltas called <literal>PDiffs</literal> for
- indexes (like <filename>Packages</filename> files) instead of downloading
- whole ones. True by default.</para>
+ indexes (like <filename>Packages</filename> files) instead of
+ downloading whole ones. True by default. Preferably, this can be set
+ for specific &sources-list; entries or index files by using the
+ <option>PDiffs</option> option there.</para>
<para>Two sub-options to limit the use of PDiffs are also available:
<literal>FileLimit</literal> can be used to specify a maximum number of
PDiff files should be downloaded to update a file. <literal>SizeLimit</literal>
</para></listitem>
</varlistentry>
+ <varlistentry><term><option>By-Hash</option></term>
+ <listitem><para>Try to download indexes via an URI constructed from a
+ hashsum of the expected file rather than downloaded via a well-known
+ stable filename. True by default, but automatically disabled if the
+ source indicates no support for it. Usage can be forced with the special
+ value "force". Preferably, this can be set for specific &sources-list; entries
+ or index files by using the <option>By-Hash</option> option there.
+ </para></listitem>
+ </varlistentry>
+
<varlistentry><term><option>Queue-Mode</option></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
</para></listitem>
</varlistentry>
+ <varlistentry><term><option>EnableSrvRecords</option></term>
+ <listitem><para>
+ This option controls if apt will use the DNS SRV server record
+ as specified in RFC 2782 to select an alternative server to
+ connect to.
+ The default is "true".
+ </para></listitem>
+ </varlistentry>
+
<varlistentry><term><option>AllowInsecureRepositories</option></term>
<listitem><para>
Allow the update operation to load data files from
</para></listitem>
</varlistentry>
+ <varlistentry><term><option>Changelogs::URI</option> scope</term>
+ <listitem><para>
+ Acquiring changelogs can only be done if an URI is known from where to get them.
+ Preferable the Release file indicates this in a 'Changelogs' field. If this isn't
+ available the Label/Origin field of the Release file is used to check if a
+ <literal>Acquire::Changelogs::URI::Label::<replaceable>LABEL</replaceable></literal> or
+ <literal>Acquire::Changelogs::URI::Origin::<replaceable>ORIGIN</replaceable></literal> option
+ exists and if so this value is taken. The value in the Release file can be overridden
+ with <literal>Acquire::Changelogs::URI::Override::Label::<replaceable>LABEL</replaceable></literal>
+ or <literal>Acquire::Changelogs::URI::Override::Origin::<replaceable>ORIGIN</replaceable></literal>.
+
+ The value should be a normal URI to a text file, expect that package specific data is
+ replaced with the placeholder <literal>CHANGEPATH</literal>. The
+ value for it is: 1. if the package is from a component (e.g. <literal>main</literal>)
+ this is the first part otherwise it is omitted, 2. the first letter of source package name,
+ expect if the source package name starts with '<literal>lib</literal>' in which case it will
+ be the first four letters. 3. The complete source package name. 4. the complete name again and
+ 5. the source version.
+ The first (if present), second, third and fourth part are separated by a slash ('<literal>/</literal>')
+ and between the fourth and fifth part is an underscore ('<literal>_</literal>').
+
+ The special value '<literal>no</literal>' is available for this option indicating that
+ this source can't be used to acquire changelog files from. Another source will be tried
+ if available in this case.
+ </para></listitem>
+ </varlistentry>
+
</variablelist>
</refsect1>
+ <refsect1><title>Binary specific configuration</title>
+ <para>Especially with the introduction of the <command>apt</command> binary
+ it can be useful to set certain options only for a specific binary as
+ even options which look like they would effect only a certain binary like
+ <option>APT::Get::Show-Versions</option> effect
+ <command>apt-get</command> as well as <command>apt</command>.
+ </para>
+ <para>Setting an option for a specific binary only can be achieved by
+ setting the option inside the
+ <option>Binary::<replaceable>specific-binary</replaceable></option>
+ scope. Setting the option <option>APT::Get::Show-Versions</option> for
+ the <command>apt</command> only can e.g. by done by setting
+ <option>Binary::apt::APT::Get::Show-Versions</option> instead.</para>
+ <para>Note that as seen in the DESCRIPTION section further above you can't
+ set binary-specific options on the commandline itself nor in
+ configuration files loaded via the commandline.</para>
+ </refsect1>
+
<refsect1><title>Directories</title>
<para>The <literal>Dir::State</literal> section has directories that pertain to local
<para>
The configuration item <literal>RootDir</literal> has a special
- meaning. If set, all paths in <literal>Dir::</literal> will be
+ meaning. If set, all paths will be
relative to <literal>RootDir</literal>, <emphasis>even paths that
are specified absolutely</emphasis>. So, for instance, if
<literal>RootDir</literal> is set to
<filename>/var/lib/dpkg/status</filename>, then the status file
will be looked up in
<filename>/tmp/staging/var/lib/dpkg/status</filename>.
+ If you want to prefix only relative paths, set <literal>Dir</literal> instead.
</para>
<para>
install to the commands, one per line on the requested file descriptor, defaulting
to standard input.</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 3 adds the architecture and <literal>MultiArch</literal>
- flag to each version being dumped.</para>
+ <para>Version 2 of this protocol sends more information through the requested
+ file descriptor: a line with the text <literal>VERSION 2</literal>,
+ the APT configuration space, and a list of package actions with filename
+ and version information.</para>
+
+ <para>Each configuration directive line has the form
+ <literal>key=value</literal>. Special characters (equal signs, newlines,
+ nonprintable characters, quotation marks, and percent signs in
+ <literal>key</literal> and newlines, nonprintable characters, and percent
+ signs in <literal>value</literal>) are %-encoded. Lists are represented
+ by multiple <literal>key::=value</literal> lines with the same key. The
+ configuration section ends with a blank line.</para>
+
+ <para>Package action lines consist of five fields in Version 2: old version, direction
+ of version change (< for upgrades, > for downgrades, = for no
+ change), new version, action. The version fields are "-" for no version
+ at all (for example when installing a package for the first time; no
+ version is treated as earlier than any real version, so that is an
+ upgrade, indicated as <literal>- < 1.23.4</literal>). The action field
+ is "**CONFIGURE**" if the package is being configured, "**REMOVE**" if it
+ is being removed, or the filename of a .deb file if it is being
+ unpacked.</para>
+
+ <para>In Version 3 after each version field follows the architecture
+ of this version, which is "-" if there is no version, and a field showing
+ the MultiArch type "same", foreign", "allowed" or "none". Note that "none"
+ is an incorrect typename which is just kept to remain compatible, it
+ should be read as "no" and users are encouraged to support both.</para>
<para>The version of the protocol to be used for the command
<literal><replaceable>cmd</replaceable></literal> can be chosen by setting