chiark / gitweb /
man: properly refer to $MAINPID instead of $(MAINPID) which doesnt work anymore
[elogind.git] / man / systemd.service.xml
index bceb5aa110232043c157574540ed2c858c933cea..4473c3d9455d1147929d21492ed58546074a363d 100644 (file)
                                 start-up type for this service
                                 unit. One of <option>simple</option>,
                                 <option>forking</option>,
                                 start-up type for this service
                                 unit. One of <option>simple</option>,
                                 <option>forking</option>,
-                                <option>finish</option>,
+                                <option>oneshot</option>,
                                 <option>dbus</option>,
                                 <option>notify</option>.</para>
 
                                 <option>dbus</option>,
                                 <option>notify</option>.</para>
 
                                 configured with
                                 <varname>ExecStart=</varname> is the
                                 main process of the service. In this
                                 configured with
                                 <varname>ExecStart=</varname> is the
                                 main process of the service. In this
-                                mode, communication channels must be
-                                installed before the daemon is started
-                                up (e.g. sockets set up by systemd,
-                                via socket activation), as systemd
-                                will immediately proceed starting
-                                follow-up units.</para>
+                                mode, if the process offers
+                                functionality to other processes on
+                                the system its communication channels
+                                should be installed before the daemon
+                                is started up (e.g. sockets set up by
+                                systemd, via socket activation), as
+                                systemd will immediately proceed
+                                starting follow-up units.</para>
 
                                 <para>If set to
                                 <option>forking</option> it is
                                 expected that the process configured
                                 with <varname>ExecStart=</varname>
 
                                 <para>If set to
                                 <option>forking</option> it is
                                 expected that the process configured
                                 with <varname>ExecStart=</varname>
-                                will start up and call
-                                <function>fork()</function>. The
-                                parent process is expected to finish
-                                when start-up is complete and all
-                                communication channels set up. The
-                                child continues to run as the main
-                                daemon process. This is the behaviour
-                                of traditional UNIX daemons. If this
+                                will call <function>fork()</function>
+                                as part of its start-up. The parent process is
+                                expected to exit when start-up is
+                                complete and all communication
+                                channels set up. The child continues
+                                to run as the main daemon
+                                process. This is the behaviour of
+                                traditional UNIX daemons. If this
                                 setting is used, it is recommended to
                                 also use the
                                 <varname>PIDFile=</varname> option, so
                                 setting is used, it is recommended to
                                 also use the
                                 <varname>PIDFile=</varname> option, so
                                 exits.</para>
 
                                 <para>Behaviour of
                                 exits.</para>
 
                                 <para>Behaviour of
-                                <option>finish</option> is similar
+                                <option>oneshot</option> is similar
                                 to <option>simple</option>, however
                                 it is expected that the process has to
                                 exit before systemd starts follow-up
                                 to <option>simple</option>, however
                                 it is expected that the process has to
                                 exit before systemd starts follow-up
-                                units. <varname>ValidNoProcess=</varname>
+                                units. <varname>RemainAfterExit=</varname>
                                 is particularly useful for this type
                                 of service.</para>
 
                                 is particularly useful for this type
                                 of service.</para>
 
                                 will proceed starting follow-up units
                                 after the D-Bus bus name has been
                                 acquired. Service units with this
                                 will proceed starting follow-up units
                                 after the D-Bus bus name has been
                                 acquired. Service units with this
-                                option configured implicitly have
+                                option configured implicitly gain
                                 dependencies on the
                                 <filename>dbus.target</filename>
                                 unit.</para>
                                 dependencies on the
                                 <filename>dbus.target</filename>
                                 unit.</para>
                                 notification message has been sent. If
                                 this option is used
                                 <varname>NotifyAccess=</varname> (see
                                 notification message has been sent. If
                                 this option is used
                                 <varname>NotifyAccess=</varname> (see
-                                below) must be set to open access to
+                                below) should be set to open access to
                                 the notification socket provided by
                                 systemd. If
                                 <varname>NotifyAccess=</varname> is not
                                 the notification socket provided by
                                 systemd. If
                                 <varname>NotifyAccess=</varname> is not
-                                set, it will be implicitly set to
+                                set, it will implicitly be set to
                                 <option>main</option>.</para>
                                 </listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <option>main</option>.</para>
                                 </listitem>
                         </varlistentry>
 
                         <varlistentry>
-                                <term><varname>ValidNoProcess=</varname></term>
+                                <term><varname>RemainAfterExit=</varname></term>
 
                                 <listitem><para>Takes a boolean value
                                 that specifies whether the service
 
                                 <listitem><para>Takes a boolean value
                                 that specifies whether the service
                                 arguments for the process. It is
                                 mandatory to set this option for all
                                 services. This option may not be
                                 arguments for the process. It is
                                 mandatory to set this option for all
                                 services. This option may not be
-                                specified more than once. Optionally,
-                                if the absolute file name is prefixed
-                                with <literal>@</literal>, the second
-                                token will be passed as
+                                specified more than once, except when
+                                <varname>Type=oneshot</varname> is
+                                used in which case more than one
+                                <varname>ExecStart=</varname> line is
+                                accepted which are then invoked one by
+                                one, sequentially in the order they
+                                appear in the unit file.</para>
+
+                                <para>Optionally, if the absolute file
+                                name is prefixed with
+                                <literal>@</literal>, the second token
+                                will be passed as
                                 <literal>argv[0]</literal> to the
                                 executed process, followed by the
                                 <literal>argv[0]</literal> to the
                                 executed process, followed by the
-                                further arguments specified. Unless
-                                <varname>Type=forking</varname> is set,
-                                the process started via this command
-                                line will be considered the main
-                                process of the
-                                daemon.</para></listitem>
+                                further arguments specified. If the
+                                first token is prefixed with
+                                <literal>-</literal> an exit code of
+                                the command normally considered a
+                                failure (i.e. non-zero exit status or
+                                abormal exit due to signal) is ignored
+                                and considered success. If both
+                                <literal>-</literal> and
+                                <literal>@</literal> are used for the
+                                same command the former must preceed
+                                the latter. Unless
+                                <varname>Type=forking</varname> is
+                                set, the process started via this
+                                command line will be considered the
+                                main process of the daemon. The
+                                command line accepts % specifiers as
+                                described in
+                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. On
+                                top of that basic environment variable
+                                substitution is supported, where
+                                <literal>${FOO}</literal> is replaced
+                                by the string value of the environment
+                                variable of the same name. Also
+                                <literal>$FOO</literal> may appear as
+                                separate word on the command line in
+                                which case the variable is replaced by
+                                its value split at whitespaces. Note
+                                that the first argument (i.e. the
+                                binary to execute) may not be a
+                                variable, and must be a literal and
+                                absolute path name.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                         </varlistentry>
 
                         <varlistentry>
                                 <listitem><para>Additional commands
                                 that are executed before (resp. after)
                                 the command in
                                 <listitem><para>Additional commands
                                 that are executed before (resp. after)
                                 the command in
-                                <varname>ExecStart=</varname>. If
-                                specified more than once, all commands
-                                are executed one after the other,
-                                serially. Use of these settings is
-                                optional.</para></listitem>
+                                <varname>ExecStart=</varname>. Multiple
+                                command lines may be concatenated in a
+                                single directive, by separating them
+                                by semicolons (these semicolons must
+                                be passed as separate words). In that
+                                case, the commands are executed one
+                                after the other,
+                                serially. Alternatively, these
+                                directives may be specified more than
+                                once whith the same effect. However,
+                                the latter syntax is not recommended
+                                for compatibility with parsers
+                                suitable for XDG
+                                <filename>.desktop</filename> files.
+                                Use of these settings is
+                                optional. Specifier and environment
+                                variable substitution is
+                                supported.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><varname>ExecReload=</varname></term>
                                 <listitem><para>Commands to execute to
                                 trigger a configuration reload in the
                         </varlistentry>
 
                         <varlistentry>
                                 <term><varname>ExecReload=</varname></term>
                                 <listitem><para>Commands to execute to
                                 trigger a configuration reload in the
-                                service. If used more than once, all
-                                commands are executed one after the
-                                other, serially. Use of this setting is optional.
-                                </para></listitem>
+                                service. This argument takes multiple
+                                command lines, following the same
+                                scheme as pointed out for
+                                <varname>ExecStartPre=</varname>
+                                above. Use of this setting is
+                                optional. Specifier and environment
+                                variable substitution is supported
+                                here following the same scheme as for
+                                <varname>ExecStart=</varname>. One
+                                special environment variable is set:
+                                if known <literal>$MAINPID</literal> is
+                                set to the main process of the
+                                daemon, and may be used for command
+                                lines like the following:
+                                <command>/bin/kill -HUP
+                                $MAINPID</command>.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><varname>ExecStop=</varname></term>
                                 <listitem><para>Commands to execute to
                                 stop the service started via
                         </varlistentry>
 
                         <varlistentry>
                                 <term><varname>ExecStop=</varname></term>
                                 <listitem><para>Commands to execute to
                                 stop the service started via
-                                <varname>ExecStart=</varname>. If used
-                                more than once, all commands are
-                                executed one after the other,
-                                serially. Use of this setting is
+                                <varname>ExecStart=</varname>. This
+                                argument takes multiple command lines,
+                                following the same scheme as pointed
+                                out for
+                                <varname>ExecStartPre=</varname>
+                                above. Use of this setting is
                                 optional. All processes remaining for
                                 a service after the commands
                                 configured in this option are run are
                                 optional. All processes remaining for
                                 a service after the commands
                                 configured in this option are run are
                                 (see below). If this option is not
                                 specified the process is terminated
                                 right-away when service stop is
                                 (see below). If this option is not
                                 specified the process is terminated
                                 right-away when service stop is
-                                requested.</para></listitem>
+                                requested. Specifier and environment
+                                variable substitution is supported
+                                (including
+                                <literal>$MAINPID</literal>, see
+                                above).</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                         </varlistentry>
 
                         <varlistentry>
                                 that are executed after the service
                                 was stopped using the commands
                                 configured in
                                 that are executed after the service
                                 was stopped using the commands
                                 configured in
-                                <varname>ExecStop=</varname>. If
-                                specified more than once, all commands
-                                are executed one after the other,
-                                serially. Use of these settings is
-                                optional.</para></listitem>
+                                <varname>ExecStop=</varname>. This
+                                argument takes multiple command lines,
+                                following the same scheme as pointed
+                                out for
+                                <varname>ExecStartPre</varname>. Use
+                                of these settings is
+                                optional. Specifier and environment
+                                variable substitution is
+                                supported.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                         </varlistentry>
 
                         <varlistentry>
                         <varlistentry>
                                 <term><varname>Restart=</varname></term>
                                 <listitem><para>Configures whether the
                         <varlistentry>
                                 <term><varname>Restart=</varname></term>
                                 <listitem><para>Configures whether the
-                                main service process shall be restarted when
-                                it exists. Takes one of
-                                <option>once</option>,
-                                <option>restart-on-success</option> or
-                                <option>restart-always</option>. If
-                                set to <option>once</option> (the
-                                default) the service will not be
-                                restarted when it exits. If set to
-                                <option>restart-on-success</option> it
-                                will be restarted only when it exited
-                                cleanly, i.e. terminated with an exit
-                                code of 0. If set to
-                                <option>restart-always</option> the
+                                main service process shall be
+                                restarted when it exists. Takes one of
+                                <option>no</option>,
+                                <option>on-success</option>,
+                                <option>on-failure</option>,
+                                <option>on-abort</option> or
+                                <option>always</option>. If set to
+                                <option>no</option> (the default) the
+                                service will not be restarted when it
+                                exits. If set to
+                                <option>on-success</option> it will be
+                                restarted only when it exited cleanly,
+                                i.e. terminated with an exit code of
+                                0. If set to
+                                <option>on-failure</option> it will be
+                                restared only when it exited with an
+                                exit code not equalling 0, or when
+                                terminated by a signal. If set to
+                                <option>on-abort</option> it will be
+                                restarted only if it exits due to
+                                reception of an uncaught signal. If
+                                set to <option>always</option> the
                                 service will be restarted regardless
                                 whether it exited cleanly or not, or
                                 got terminated abnormally by a
                                 service will be restarted regardless
                                 whether it exited cleanly or not, or
                                 got terminated abnormally by a
                                 <varname>Type=notify</varname> (see above).</para></listitem>
                         </varlistentry>
 
                                 <varname>Type=notify</varname> (see above).</para></listitem>
                         </varlistentry>
 
+                        <varlistentry>
+                                <term><varname>Sockets=</varname></term>
+                                <listitem><para>Specifies the name of
+                                the socket units this service shall
+                                inherit the sockets from when the
+                                service (ignoring the different suffix
+                                of course) is started. Normally it
+                                should not be necessary to use this
+                                setting as all sockets whose unit
+                                shares the same name as the service
+                                are passed to the spawned
+                                process.</para>
+
+                                <para>Note that the same socket may be
+                                passed to multiple processes at the
+                                same time. Also note that a different
+                                service may be activated on incoming
+                                traffic than inherits the sockets. Or
+                                in other words: The
+                                <varname>Service=</varname> setting of
+                                <filename>.socket</filename> units
+                                doesn't have to match the inverse of the
+                                <varname>Sockets=</varname> setting of
+                                the <filename>.service</filename> it
+                                refers to.</para></listitem>
+                        </varlistentry>
+
                 </variablelist>
         </refsect1>
 
                 </variablelist>
         </refsect1>