+
+ <varlistentry><term><option>finger</option></term>
+ <listitem>
+ <para>
+
+ List fingerprints of trusted keys.
+
+ </para>
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry><term><option>adv</option></term>
+ <listitem>
+ <para>
+ Pass advanced options to gpg. With <command>adv --recv-key</command> you
+ can e.g. download key from keyservers directly into the the trusted set of
+ keys. Note that there are <emphasis>no</emphasis> checks performed, so it is
+ easy to completely undermine the &apt-secure; infrastructure if used without
+ care.
+ </para>
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry><term><option>update</option></term>
+ <listitem>
+ <para>
+
+ Update the local keyring with the archive keyring and remove from
+ the local keyring the archive keys which are no longer valid.
+ The archive keyring is shipped in the <literal>archive-keyring</literal> package of your
+ distribution, e.g. the &keyring-package; package in &keyring-distro;.
+
+ </para>
+
+ </listitem>
+ </varlistentry>
+
+ <varlistentry><term><option>net-update</option></term>
+ <listitem>
+ <para>
+
+ Perform an update working similarly to the <command>update</command> command above,
+ but get the archive keyring from a URI instead and validate it against a master key.
+
+ This requires an installed &wget; and an APT build configured to have
+ a server to fetch from and a master keyring to validate.
+
+ APT in Debian does not support this command, relying on
+ <command>update</command> instead, but Ubuntu's APT does.
+
+ </para>
+
+ </listitem>
+ </varlistentry>
+ </variablelist>
+</refsect1>
+
+ <refsect1><title>Options</title>
+<para>Note that options need to be defined before the commands described in the previous section.</para>
+ <variablelist>
+ <varlistentry><term><option>--keyring</option> <option>&synopsis-param-filename;</option></term>
+ <listitem><para>With this option it is possible to specify a particular keyring
+ file the command should operate on. The default is that a command is executed
+ on the <filename>trusted.gpg</filename> file as well as on all parts in the
+ <filename>trusted.gpg.d</filename> directory, though <filename>trusted.gpg</filename>
+ is the primary keyring which means that e.g. new keys are added to this one.
+ </para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1><title>Files</title>
+ <variablelist>
+
+ &file-trustedgpg;
+
+ <varlistentry><term><filename>/etc/apt/trustdb.gpg</filename></term>
+ <listitem><para>Local trust database of archive keys.</para></listitem>
+ </varlistentry>
+
+ <varlistentry><term>&keyring-filename;</term>
+ <listitem><para>Keyring of &keyring-distro; archive trusted keys.</para></listitem>
+ </varlistentry>
+
+ <varlistentry><term>&keyring-removed-filename;</term>
+ <listitem><para>Keyring of &keyring-distro; archive removed trusted keys.</para></listitem>
+ </varlistentry>
+