chiark / gitweb /
nspawn: catch config mistake of specifying -b and args
[elogind.git] / man / systemd.service.xml
index 8c1dfe18b7292ecb7bbbbf67ebf7dff6c19876d5..8977873c1ebd81c4f824defbafc7e00c59cb457d 100644 (file)
@@ -48,7 +48,7 @@
         </refnamediv>
 
         <refsynopsisdiv>
-                <para><filename>systemd.service</filename></para>
+                <para><filename><replaceable>service</replaceable>.service</filename></para>
         </refsynopsisdiv>
 
         <refsect1>
                 options specific to the <literal>[Service]</literal>
                 section of service units are the following:</para>
 
-                <variablelist>
+                <variablelist class='unit-directives'>
                         <varlistentry>
                                 <term><varname>Type=</varname></term>
 
 
                         <varlistentry>
                                 <term><varname>ExecStart=</varname></term>
-                                <listitem><para>Takes a command line
-                                that is executed when this service
-                                shall be started up. The first token
-                                of the command line must be an
-                                absolute file name, then followed by
-                                arguments for the process. It is
-                                mandatory to set this option for all
-                                services. This option may not be
-                                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>
+                                <listitem><para>Commands with their
+                                arguments that are executed when this
+                                service is started. The first
+                                argument must be an absolute path
+                                name.</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
-                                abnormal exit due to signal) is ignored
-                                and considered success. If both
-                                <literal>-</literal> and
-                                <literal>@</literal> are used they
-                                can appear in either order. Unless
+                                <para>When
+                                <varname>Type=oneshot</varname> is
+                                used, more than one command may be
+                                specified. Multiple command lines may
+                                be concatenated in a single directive,
+                                by separating them with semicolons
+                                (these semicolons must be passed as
+                                separate words). Alternatively, this
+                                directive may be specified more than
+                                once with the same effect. However,
+                                the latter syntax is not recommended
+                                for compatibility with parsers
+                                suitable for XDG
+                                <filename>.desktop</filename> files.
+                                The commands are invoked one by one
+                                sequentially in the order they appear
+                                in the unit file.  When
+                                <varname>Type</varname> is not
+                                <option>oneshot</option>, only one
+                                command may be given. Lone semicolons
+                                may be escaped as
+                                '<literal>\;</literal>'. If the empty
+                                string is assigned to this option the
+                                list of commands to start is reset,
+                                prior assignments of this option will
+                                have no effect.</para>
+
+                                <para>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
+                                main process of the daemon.</para>
+
+                                <para>The command line accepts
+                                '<literal>%</literal>' specifiers as
                                 described in
-                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Note
+                                that the first argument of the command
+                                line (i.e. the program to execute) may
+                                not include specifiers.</para>
 
                                 <para>On top of that basic environment
                                 variable substitution is
                                 at whitespace, resulting in no or more
                                 arguments. Note that the first
                                 argument (i.e. the program to execute)
-                                may not be a variable, and must be a
-                                literal and absolute path
+                                may not be a variable, since it must
+                                be a literal and absolute path
                                 name.</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
+                                absolute file name is prefixed with
+                                '<literal>-</literal>' an exit code of
+                                the command normally considered a
+                                failure (i.e. non-zero exit status or
+                                abnormal exit due to signal) is ignored
+                                and considered success. If both
+                                '<literal>-</literal>' and
+                                '<literal>@</literal>' are used they
+                                can appear in either order.</para>
+
                                 <para>Note that this setting does not
                                 directly support shell command
                                 lines. If shell command lines are to
                                 <listitem><para>Additional commands
                                 that are executed before or after
                                 the command in
-                                <varname>ExecStart=</varname>, respectively. 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 with 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>
+                                <varname>ExecStart=</varname>, respectively.
+                                Syntax is the same as for
+                                <varname>ExecStart=</varname>, except
+                                that multiple command lines are allowed
+                                and the commands are executed one
+                                after the other, serially.</para>
+                                </listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 trigger a configuration reload in the
                                 service. This argument takes multiple
                                 command lines, following the same
-                                scheme as pointed out for
-                                <varname>ExecStartPre=</varname>
+                                scheme as described for
+                                <varname>ExecStart=</varname>
                                 above. Use of this setting is
                                 optional. Specifier and environment
                                 variable substitution is supported
                                 stop the service started via
                                 <varname>ExecStart=</varname>. This
                                 argument takes multiple command lines,
-                                following the same scheme as pointed
-                                out for
-                                <varname>ExecStartPre=</varname>
+                                following the same scheme as described
+                                for <varname>ExecStart=</varname>
                                 above. Use of this setting is
                                 optional. All processes remaining for
                                 a service after the commands
                                 configured in
                                 <varname>ExecStop=</varname>. This
                                 argument takes multiple command lines,
-                                following the same scheme as pointed
-                                out for
-                                <varname>ExecStartPre</varname>. Use
+                                following the same scheme as described
+                                for <varname>ExecStart</varname>. Use
                                 of these settings is
                                 optional. Specifier and environment
                                 variable substitution is
                                 SIGKILL</literal>", ensures that exit
                                 codes 1, 2, 8 and the termination
                                 signal SIGKILL are considered clean
-                                service
-                                terminations.</para></listitem>
+                                service terminations. This option may
+                                appear more than once in which case
+                                the list of successful exit statuses
+                                is merged. If the empty string is
+                                assigned to this option the list is
+                                reset, all prior assignments of this
+                                option will have no
+                                effect.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 logic. Example:
                                 "<literal>RestartPreventExitStatus=1 6
                                 SIGABRT</literal>", ensures that exit
-                                codes 1 and 6 and the termination signal
-                                SIGABRT will not result in automatic
-                                service restarting.</para></listitem>
+                                codes 1 and 6 and the termination
+                                signal SIGABRT will not result in
+                                automatic service restarting. This
+                                option may appear more than once in
+                                which case the list of restart preventing
+                                statuses is merged. If the empty
+                                string is assigned to this option the
+                                list is reset, all prior assignments
+                                of this option will have no
+                                effect.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 open access to the notification socket
                                 when using
                                 <varname>Type=notify</varname> or
-                                <varname>WatchdogUsec=</varname> (see
+                                <varname>WatchdogSec=</varname> (see
                                 above). If those options are used but
                                 <varname>NotifyAccess=</varname> not
                                 configured it will be implicitly set
                                 same time. Also note that a different
                                 service may be activated on incoming
                                 traffic than inherits the sockets. Or
-                                in other words: The
+                                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>
+                                doesn't have to match the inverse of
+                                the <varname>Sockets=</varname>
+                                setting of the
+                                <filename>.service</filename> it
+                                refers to.</para>
+
+                                <para>This option may appear more than
+                                once, in which case the list of socket
+                                units is merged. If the empty string
+                                is assigned to this option the list of
+                                sockets is reset, all prior uses of
+                                this setting will have no
+                                effect.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                 for compatibility reasons and should not be used in
                 newly written service files.</para>
 
-                <variablelist>
+                <variablelist class='unit-directives'>
                         <varlistentry>
                                 <term><varname>SysVStartPriority=</varname></term>
                                 <listitem><para>Set the SysV start
                           <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>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                   </para>
         </refsect1>