+
+ </variablelist>
+
+ <para>The following environment variables are read by
+ the module and may be used by the PAM service to pass
+ meta data to the module:</para>
+
+ <variablelist class='environment-variables'>
+ <varlistentry>
+ <term><varname>$XDG_SESSION_TYPE</varname></term>
+
+ <listitem><para>The session type. This
+ may be used instead of
+ <option>session=</option> on the
+ module parameter line, and is usually
+ preferred.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SESSION_CLASS</varname></term>
+
+ <listitem><para>The session class. This
+ may be used instead of
+ <option>class=</option> on the
+ module parameter line, and is usually
+ preferred.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SESSION_DESKTOP</varname></term>
+
+ <listitem><para>The session
+ deskop. This may be used to indicate
+ the session desktop used, where this
+ applies. This should be a short,
+ lowercase string identifying the
+ desktop environment used if this
+ information is available. For example:
+ <literal>gnome</literal>, or
+ <literal>kde</literal>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_SEAT</varname></term>
+
+ <listitem><para>The seat name the session
+ shall be registered for, if
+ any.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_VTNR</varname></term>
+
+ <listitem><para>The VT number the
+ session shall be registered for, if
+ any. (Only applies to seats with a VT
+ available, such as
+ <literal>seat0</literal>)</para></listitem>
+ </varlistentry>
+