- or a negative errno-style error code. In particular,
- <function>sd_id128_get_machine()</function>,
- <function>sd_id128_get_machine_app_specific()</function>, and
- <function>sd_id128_get_boot_app_specific()</function> return <constant>-ENOENT</constant> if
- <filename>/etc/machine-id</filename> is missing, and <constant>-ENOMEDIUM</constant> if
- <filename>/etc/machine-id</filename> is empty or all zeros.</para>
+ or a negative errno-style error code.</para>
+
+ <refsect2>
+ <title>Errors</title>
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>-ENOENT</constant></term>
+
+ <listitem><para>Returned by <function>sd_id128_get_machine()</function> and
+ <function>sd_id128_get_machine_app_specific()</function> when <filename>/etc/machine-id</filename>
+ is missing.</para>
+
+ <xi:include href="version-info.xml" xpointer="v242"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOMEDIUM</constant></term>
+
+ <listitem><para>Returned by <function>sd_id128_get_machine()</function> and
+ <function>sd_id128_get_machine_app_specific()</function> when <filename>/etc/machine-id</filename>
+ is empty or all zeros. Also returned by <function>sd_id128_get_invocation()</function> when the
+ invocation ID is all zeros.</para>
+
+ <xi:include href="version-info.xml" xpointer="v242"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOPKG</constant></term>
+
+ <listitem><para>Returned by <function>sd_id128_get_machine()</function> and
+ <function>sd_id128_get_machine_app_specific()</function> when the content of
+ <filename>/etc/machine-id</filename> is <literal>uninitialized</literal>.</para>
+
+ <xi:include href="version-info.xml" xpointer="v253"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOSYS</constant></term>
+
+ <listitem><para>Returned by <function>sd_id128_get_boot()</function> and
+ <function>sd_id128_get_boot_app_specific()</function> when <filename>/proc/</filename> is not
+ mounted.</para>
+
+ <xi:include href="version-info.xml" xpointer="v253"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENXIO</constant></term>
+
+ <listitem><para>Returned by <function>sd_id128_get_invocation()</function> if no invocation ID is
+ set. Also returned by <function>sd_id128_get_app_specific()</function>,
+ <function>sd_id128_get_machine_app_specific()</function>, and
+ <function>sd_id128_get_boot_app_specific()</function> when the <parameter>app_id</parameter>
+ parameter is all zeros.</para>
+
+ <xi:include href="version-info.xml" xpointer="v242"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EUCLEAN</constant></term>
+
+ <listitem><para>Returned by any of the functions described here when the configured value has
+ invalid format.</para>
+
+ <xi:include href="version-info.xml" xpointer="v253"/></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EPERM</constant></term>
+
+ <listitem><para>Requested information could not be retrieved because of insufficient permissions.
+ </para>
+
+ <xi:include href="version-info.xml" xpointer="v242"/></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>