chiark / gitweb /
timer: when deserializing timer state stay elapsed when we are elapsed
[elogind.git] / man / systemd.unit.xml
index 3bc5d3c66f6f8453712ffdbcc481cb1ca8467463..14da607a95f1f3288bb93455812d779c4b7056a8 100644 (file)
                 <literal>%i</literal> specifier in many of the
                 configuration options. Other specifiers that may be
                 used are <literal>%n</literal>, <literal>%N</literal>,
-                <literal>%p</literal>, <literal>%P</literal> and
-                <literal>%I</literal>, for the full unit name, the
-                unescaped unit name, the prefix name, the unescaped
-                prefix name and the unescaped instance name,
-                respectively. The prefix name here refers to the
-                string before the @, i.e. "getty" in the example
-                above, where "tty3" is the instance name.</para>
+                <literal>%p</literal>, <literal>%P</literal>,
+                <literal>%I</literal> and <literal>%f</literal>, for
+                the full unit name, the unescaped unit name, the
+                prefix name, the unescaped prefix name, the unescaped
+                instance name and the unescaped filename,
+                respectively. The unescaped filename is either the
+                unescaped instance name (if set) with / prepended (if
+                necessary), or the prefix name similarly prepended
+                with /. The prefix name here refers to the string
+                before the @, i.e. "getty" in the example above, where
+                "tty3" is the instance name.</para>
+
+                <para>If a unit file is empty (i.e. has the file size
+                0) or is symlinked to <filename>/dev/null</filename>
+                its configuration will not be loaded and it appears
+                with a load state of <literal>masked</literal>, and
+                cannot be activated. Use this as an effective way to
+                fully disable a unit, making it impossible to start it
+                even manually.</para>
+
+                <para>The unit file format is covered by the
+                <ulink
+                url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
+                Stability Promise</ulink>.</para>
         </refsect1>
 
         <refsect1>
                         </varlistentry>
 
                         <varlistentry>
-                                <term><varname>RecursiveStop=</varname></term>
+                                <term><varname>StopRetroactively=</varname></term>
 
                                 <listitem><para>Takes a boolean
                                 argument. If <option>true</option> and
-                                the unit stops without being requested
-                                by the user, all units
-                                depending on it will be stopped as
+                                a unit this unit requires stops
+                                without this being requested by the
+                                user, this unit will be stopped as
                                 well. (e.g. if a service exits or
-                                crashes on its own behalf, units using
-                                it will be stopped) Note that normally
-                                if a unit stops without a user request,
+                                crashes on its own behalf, units this
+                                flag is set for that require it will
+                                be stopped.) Note that normally if a
+                                unit stops without a user request,
                                 units depending on it will not be
                                 terminated. Only if the user requested
-                                shutdown of a unit, all units depending
-                                on that unit will be shut down as well
-                                and at the same time. Defaults to
+                                shutdown of a unit, all units
+                                depending on that unit will be shut
+                                down as well and at the same
+                                time. Defaults to
                                 <option>false</option>.</para></listitem>
                         </varlistentry>
 
                                 change.</para></listitem>
                         </varlistentry>
 
+                        <varlistentry>
+                                <term><varname>ConditionPathExists=</varname></term>
+                                <term><varname>ConditionKernelCommandLine=</varname></term>
+
+                                <listitem><para>Before starting a unit
+                                verify that the specified condition is
+                                true. With
+                                <varname>ConditionPathExists=</varname>
+                                a file existance condition can be
+                                checked before a unit is started. If
+                                the specified absolute path name does
+                                not exist startup of a unit will not
+                                actually happen, however the unit is
+                                still useful for ordering purposes in
+                                this case. The condition is checked at
+                                the time the queued start job is to be
+                                executed. If the absolute path name
+                                passed to
+                                <varname>ConditionPathExists=</varname>
+                                is prefixed with an exclamation mark
+                                (!), the test is negated, and the unit
+                                only started if the path does not
+                                exist. Similarly
+                                <varname>ConditionKernelCommandLine=</varname>
+                                may be used to check whether a
+                                specific kernel command line option is
+                                set (or if prefixed with the
+                                exclamation mark unset). The argument
+                                must either be a single word, or an
+                                assignment (i.e. two words, seperated
+                                by the equality sign). In the former
+                                case the kernel command line is search
+                                for the word appearing as is, or as
+                                left hand side of an assignment. In
+                                the latter case the exact assignment
+                                is looked for with right and left hand
+                                side matching. If multiple conditions
+                                are specified the unit will be
+                                executed iff at least one of them
+                                apply (i.e. a logical OR is
+                                applied).</para></listitem>
+                        </varlistentry>
                 </variablelist>
 
                 <para>Unit file may include a [Install] section, which