X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/a23dcda4a75ead3ef9712d90300f45155856b6ce..46e39c8e14dc98045107cfb38af8cecb8a4773b0:/doc/apt_preferences.5.xml
diff --git a/doc/apt_preferences.5.xml b/doc/apt_preferences.5.xml
index 12b03196a..159d61f2b 100644
--- a/doc/apt_preferences.5.xml
+++ b/doc/apt_preferences.5.xml
@@ -14,12 +14,13 @@
&apt-email;
&apt-product;
<!-- The last update date -->
- <date>29 February 2004</date>
+ <date>04 May 2009</date>
</refentryinfo>
<refmeta>
<refentrytitle>apt_preferences</refentrytitle>
<manvolnum>5</manvolnum>
+ <refmiscinfo class="manual">APT</refmiscinfo>
</refmeta>
<!-- Man page title -->
@@ -31,7 +32,8 @@
<refsect1>
<title>Description</title>
<para>The APT preferences file <filename>/etc/apt/preferences</filename>
-can be used to control which versions of packages will be selected
+and the fragment files in the <filename>/etc/apt/preferences.d/</filename>
+folder can be used to control which versions of packages will be selected
for installation.</para>
<para>Several versions of a package may be available for installation when
@@ -60,6 +62,9 @@ belongs. It is possible to single out a distribution, "the target release",
which receives a higher priority than other distributions do by default.
The target release can be set on the <command>apt-get</command> command
line or in the APT configuration file <filename>/etc/apt/apt.conf</filename>.
+Note that this has precedence over any general priority you set in the
+<filename>/etc/apt/preferences</filename> file described later, but not
+over specifically pinned packages.
For example,
<programlisting>
@@ -143,10 +148,11 @@ separated by blank lines. Records can have one of two forms, a specific form
and a general form.
<itemizedlist>
<listitem>
-<simpara>The specific form assigns a priority (a "Pin-Priority") to a
-specified package and specified version or version range. For example,
+<simpara>The specific form assigns a priority (a "Pin-Priority") to one or more
+specified packages and specified version or version range. For example,
the following record assigns a high priority to all versions of
-the <filename>perl</filename> package whose version number begins with "<literal>5.8</literal>".</simpara>
+the <filename>perl</filename> package whose version number begins with "<literal>5.8</literal>".
+Multiple packages can be separated by spaces.</simpara>
<programlisting>
Package: perl
@@ -183,7 +189,16 @@ belonging to any distribution whose Archive name is "<literal>unstable</literal>
<programlisting>
Package: *
Pin: release a=unstable
-Pin-Priority: 500
+Pin-Priority: 50
+</programlisting>
+
+<simpara>The following record assigns a high priority to all package versions
+belonging to any distribution whose Codename is "<literal>squeeze</literal>".</simpara>
+
+<programlisting>
+Package: *
+Pin: release n=squeeze
+Pin-Priority: 900
</programlisting>
<simpara>The following record assigns a high priority to all package versions
@@ -323,10 +338,11 @@ file are relevant for setting APT priorities:
<variablelist>
<varlistentry>
-<term>the <literal>Archive:</literal> line</term>
+<term>the <literal>Archive:</literal> or <literal>Suite:</literal> line</term>
<listitem><simpara>names the archive to which all the packages
in the directory tree belong. For example, the line
-"Archive: stable"
+"Archive: stable" or
+"Suite: stable"
specifies that all of the packages in the directory
tree below the parent of the <filename>Release</filename> file are in a
<literal>stable</literal> archive. Specifying this value in the APT preferences file
@@ -338,6 +354,22 @@ Pin: release a=stable
</listitem>
</varlistentry>
+<varlistentry>
+<term>the <literal>Codename:</literal> line</term>
+<listitem><simpara>names the codename to which all the packages
+in the directory tree belong. For example, the line
+"Codename: squeeze"
+specifies that all of the packages in the directory
+tree below the parent of the <filename>Release</filename> file belong to a version named
+<literal>squeeze</literal>. Specifying this value in the APT preferences file
+would require the line:
+</simpara>
+<programlisting>
+Pin: release n=squeeze
+</programlisting>
+</listitem>
+</varlistentry>
+
<varlistentry>
<term>the <literal>Version:</literal> line</term>
<listitem><simpara>names the release version. For example, the
@@ -421,7 +453,7 @@ one or more lines beginning with the word <literal>Explanation:</literal>.
This provides a place for comments.</para>
<para>The <literal>Pin-Priority:</literal> line in each APT preferences record is
-optional. If omitted, APT assigs a priority of 1 less than the last value
+optional. If omitted, APT assigns a priority of 1 less than the last value
specified on a line beginning with <literal>Pin-Priority: release ...</literal>.</para>
</refsect2>
</refsect1>
@@ -518,10 +550,74 @@ version.
apt-get install <replaceable>package</replaceable>/unstable
</programlisting>
</para>
+</refsect2>
+
+<refsect2>
+<title>Tracking the evolution of a codename release</title>
+
+<para>The following APT preferences file will cause APT to assign a
+priority higher than the default (500) to all package versions belonging
+to a specified codename of a distribution and a prohibitively low priority to
+package versions belonging to other <literal>Debian</literal> distributions,
+codenames and archives.
+Note that with this APT preference APT will follow the migration of a release
+from the archive <literal>testing</literal> to <literal>stable</literal> and
+later <literal>oldstable</literal>. If you want to follow for example the progress
+in <literal>testing</literal> notwithstanding the codename changes you should use
+the example configurations above.
+
+<programlisting>
+Explanation: Uninstall or do not install any Debian-originated package versions
+Explanation: other than those in the distribution codenamed with squeeze or sid
+Package: *
+Pin: release n=squeeze
+Pin-Priority: 900
+
+Explanation: Debian unstable is always codenamed with sid
+Package: *
+Pin: release a=sid
+Pin-Priority: 800
+
+Package: *
+Pin: release o=Debian
+Pin-Priority: -10
+</programlisting>
+</para>
+
+<para>With a suitable &sources-list; file and the above preferences file,
+any of the following commands will cause APT to upgrade to the
+latest version(s) in the release codenamed with <literal>squeeze</literal>.
+
+<programlisting>
+apt-get install <replaceable>package-name</replaceable>
+apt-get upgrade
+apt-get dist-upgrade
+</programlisting>
+</para>
+
+<para>The following command will cause APT to upgrade the specified
+package to the latest version from the <literal>sid</literal> distribution.
+Thereafter, <command>apt-get upgrade</command> will upgrade
+the package to the most recent <literal>squeeze</literal> version if that is
+more recent than the installed version, otherwise, to the most recent
+<literal>sid</literal> version if that is more recent than the installed
+version.
+
+<programlisting>
+apt-get install <replaceable>package</replaceable>/sid
+</programlisting>
+</para>
</refsect2>
</refsect1>
+<refsect1>
+<title>Files</title>
+ <variablelist>
+ &file-preferences;
+ </variablelist>
+</refsect1>
+
<refsect1>
<title>See Also</title>
<para>&apt-get; &apt-cache; &apt-conf; &sources-list;
@@ -531,4 +627,3 @@ apt-get install <replaceable>package</replaceable>/unstable
&manbugs;
</refentry>
-