man: document Sockets= switch

[elogind.git] / man / systemd.service.xml

diff --git a/man/systemd.service.xml b/man/systemd.service.xml
index c6fdc0d50485ed050b31f94300ead0e9d78ae3b5..8f455ea4c721fd74874fba38c35cd12568baa43c 100644 (file)
--- a/man/systemd.service.xml
+++ b/man/systemd.service.xml
@@ -55,32 +55,61 @@
                 <title>Description</title>
 
                 <para>A unit configuration file whose name ends in
                 <title>Description</title>
 
                 <para>A unit configuration file whose name ends in

-                .service encodes information about a process
-                controlled and supervised by systemd.</para>
+                <filename>.service</filename> encodes information
+                about a process controlled and supervised by
+                systemd.</para>

 
                 <para>This man page lists the configuration options
                 specific to this unit type. See
                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 for the common options of all unit configuration
                 files. The common configuration items are configured
 
                 <para>This man page lists the configuration options
                 specific to this unit type. See
                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 for the common options of all unit configuration
                 files. The common configuration items are configured

-                in the generic [Unit] and [Install] sections. The
-                service specific configuration options are configured
-                in the [Service] section.</para>
-
-                <para>Additional options are listed in <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+                in the generic <literal>[Unit]</literal> and
+                <literal>[Install]</literal> sections. The service
+                specific configuration options are configured in the
+                <literal>[Service]</literal> section.</para>
+
+                <para>Additional options are listed in
+                <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                which define the execution environment the commands
+                are executed in.</para>
+
+                <para>Unless <varname>DefaultDependencies=</varname>
+                is set to <option>false</option>, service units will
+                implicitly have dependencies of type
+                <varname>Requires=</varname> and
+                <varname>After=</varname> on
+                <filename>basic.target</filename> as well as
+                dependencies of type <varname>Conflicts=</varname> and
+                <varname>Before=</varname> on
+                <filename>shutdown.target</filename>. These ensure
+                that normal service units pull in basic system
+                initialization, and are terminated cleanly prior to
+                system shutdown. Only services involved with early
+                boot or late system shutdown should disable this
+                option.</para>
+
+                <para>If a service is requested under a certain name
+                but no unit configuration file is found, systemd looks
+                for a SysV init script by the same name (with the
+                <filename>.service</filename> suffix removed) and
+                dynamically creates a service unit from that
+                script. This is useful for compatibility with
+                SysV.</para>

         </refsect1>
 
         <refsect1>
                 <title>Options</title>
 
         </refsect1>
 
         <refsect1>
                 <title>Options</title>
 

-                <para>Service files must include a [Service] section,
-                which carries information about the service and the
-                process it supervises. A number of options that may be
-                used in this section are shared with other unit
-                types. These options are documented in
+                <para>Service files must include a
+                <literal>[Service]</literal> section, which carries
+                information about the service and the process it
+                supervises. A number of options that may be used in
+                this section are shared with other unit types. These
+                options are documented in

                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The

-                options specific to the [Service] section of service
-                units are the following:</para>
+                options specific to the <literal>[Service]</literal>
+                section of service units are the following:</para>

 
                 <variablelist>
                         <varlistentry>
 
                 <variablelist>
                         <varlistentry>


@@ -90,7 +119,7 @@
                                 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>
 


@@ -100,25 +129,27 @@
                                 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


@@ -129,24 +160,28 @@
                                 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>
 
                                 <para>Behaviour of
                                 <option>dbus</option> is similar to
                                 is particularly useful for this type
                                 of service.</para>
 
                                 <para>Behaviour of
                                 <option>dbus</option> is similar to

-                                <option>simple</option>, however it
-                                is expected that the daemon acquires a
+                                <option>simple</option>, however it is
+                                expected that the daemon acquires a

                                 name on the D-Bus bus, as configured
                                 by
                                 <varname>BusName=</varname>. systemd
                                 will proceed starting follow-up units
                                 after the D-Bus bus name has been
                                 name on the D-Bus bus, as configured
                                 by
                                 <varname>BusName=</varname>. systemd
                                 will proceed starting follow-up units
                                 after the D-Bus bus name has been

-                                acquired.</para>
+                                acquired. Service units with this
+                                option configured implicitly gain
+                                dependencies on the
+                                <filename>dbus.target</filename>
+                                unit.</para>

 
                                 <para>Behaviour of
                                 <option>notify</option> is similar to
 
                                 <para>Behaviour of
                                 <option>notify</option> is similar to


@@ -159,15 +194,18 @@
                                 starting follow-up units after this
                                 notification message has been sent. If
                                 this option is used
                                 starting follow-up units after this
                                 notification message has been sent. If
                                 this option is used

-                                <option>NotifyAccess=</option> (see
-                                below) must be set to open access to
+                                <varname>NotifyAccess=</varname> (see
+                                below) should be set to open access to

                                 the notification socket provided by
                                 the notification socket provided by

-                                systemd.</para>
+                                systemd. If
+                                <varname>NotifyAccess=</varname> is not
+                                set, it will implicitly be set to
+                                <option>main</option>.</para>

                                 </listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 </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


@@ -214,17 +252,51 @@
                                 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 @, the second token will be
-                                passed as argv[0] to the executed
-                                process, followed by the further
-                                arguments specified. Unless
-                                <option>Type=forking</option> is set,
-                                the process started via this command
-                                line will be considered the main
-                                process of the
-                                daemon.</para></listitem>
+                                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
+                                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>


@@ -233,31 +305,58 @@
                                 <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 seperating 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


@@ -266,7 +365,11 @@
                                 (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>


@@ -275,11 +378,15 @@
                                 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>


@@ -308,7 +415,7 @@
                                 forcibly via SIGTERM, and after
                                 another delay of this time with
                                 SIGKILL. (See
                                 forcibly via SIGTERM, and after
                                 another delay of this time with
                                 SIGKILL. (See

-                                <option>KillMode=</option>
+                                <varname>KillMode=</varname>

                                 below.) Takes a unit-less value in seconds, or a
                                 time span value such as "5min
                                 20s". Pass 0 to disable the timeout
                                 below.) Takes a unit-less value in seconds, or a
                                 time span value such as "5min
                                 20s". Pass 0 to disable the timeout


@@ -321,17 +428,17 @@
                                 <listitem><para>Configures whether the
                                 main service process shall be restarted when
                                 it exists. Takes one of
                                 <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
+                                <option>no</option>,
+                                <option>on-success</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
                                 default) the service will not be
                                 restarted when it exits. If set to

-                                <option>restart-on-success</option> it
+                                <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
                                 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
+                                <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


@@ -446,7 +553,7 @@
                                 <para>Processes will first be
                                 terminated via SIGTERM. If then after
                                 a delay (configured via the
                                 <para>Processes will first be
                                 terminated via SIGTERM. If then after
                                 a delay (configured via the

-                                <option>TimeoutSec=</option> option)
+                                <varname>TimeoutSec=</varname> option)

                                 processes still remain, the
                                 termination request is repeated with
                                 the SIGKILL signal. See
                                 processes still remain, the
                                 termination request is repeated with
                                 the SIGKILL signal. See


@@ -495,13 +602,40 @@
                                 <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> setiing of
+                                the <filename>.service</filename> it
+                                refers to.</para></listitem>
+                        </varlistentry>
+

                 </variablelist>
         </refsect1>
 
         <refsect1>
                   <title>See Also</title>
                   <para>
                 </variablelist>
         </refsect1>
 
         <refsect1>
                   <title>See Also</title>
                   <para>

-                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,

                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>