+
+ <para><function>sd_session_get_service()</function>
+ may be used to determine the name of the service (as
+ passed during PAM session setup) that registered the
+ session identified by the specified session
+ identifier. The returned string needs to be freed with
+ the libc
+ <citerefentry><refentrytitle>free</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ call after use.</para>
+
+ <para>If the <literal>session</literal> parameter of
+ any of these functions is passed as NULL the operation
+ is executed for the session the calling process is a
+ member of, if there is any.</para>