chiark / gitweb /
man: document $MAINPID
[elogind.git] / man / systemd.service.xml
index 0cb3d9e..3b2a7cf 100644 (file)
                 script. This is useful for compatibility with
                 SysV. Note that this compatibility is quite
                 comprehensive but not 100%. For details about the
-                incompatibilities see the <ulink
+                incompatibilities, see the <ulink
                 url="http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
                 with SysV</ulink> document.
                 </para>
 
                                 <para>If set to
                                 <option>simple</option> (the default
-                                value if <varname>BusName=</varname>
-                                is not specified), it is expected that
-                                the process configured with
+                                value if neither
+                                <varname>Type=</varname> nor
+                                <varname>BusName=</varname> are
+                                specified), it is expected that the
+                                process configured with
                                 <varname>ExecStart=</varname> is the
                                 main process of the service. In this
                                 mode, if the process offers
                                 <varname>PIDFile=</varname> option, so
                                 that systemd can identify the main
                                 process of the daemon. systemd will
-                                proceed starting follow-up units as
-                                soon as the parent process
+                                proceed with starting follow-up units
+                                as soon as the parent process
                                 exits.</para>
 
                                 <para>Behavior of
                                 <option>oneshot</option> is similar
-                                to <option>simple</option>, however
+                                to <option>simple</option>; however,
                                 it is expected that the process has to
                                 exit before systemd starts follow-up
                                 units. <varname>RemainAfterExit=</varname>
 
                                 <para>Behavior of
                                 <option>dbus</option> is similar to
-                                <option>simple</option>, however it is
+                                <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
+                                will proceed with starting follow-up
+                                units after the D-Bus bus name has been
                                 acquired. Service units with this
                                 option configured implicitly gain
                                 dependencies on the
 
                                 <para>Behavior of
                                 <option>notify</option> is similar to
-                                <option>simple</option>, however it is
+                                <option>simple</option>; however, it is
                                 expected that the daemon sends a
                                 notification message via
                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
-                                or an equivalent call when it finished
-                                starting up. systemd will proceed
+                                or an equivalent call when it has finished
+                                starting up. systemd will proceed with
                                 starting follow-up units after this
                                 notification message has been sent. If
                                 this option is used,
 
                                 <para>Behavior of
                                 <option>idle</option> is very similar
-                                to <option>simple</option>, however
+                                to <option>simple</option>; however,
                                 actual execution of the service
                                 binary is delayed until all jobs are
                                 dispatched. This may be used to avoid
                                 is set and <option>PIDFile=</option>
                                 is unset because for the other types
                                 or with an explicitly configured PID
-                                file the main PID is always known. The
+                                file, the main PID is always known. The
                                 guessing algorithm might come to
                                 incorrect conclusions if a daemon
                                 consists of more than one process. If
                                 <term><varname>BusName=</varname></term>
 
                                 <listitem><para>Takes a D-Bus bus
-                                name, that this service is reachable
+                                name that this service is reachable
                                 as. This option is mandatory for
                                 services where
                                 <varname>Type=</varname> is set to
                                 <option>dbus</option>, but its use
-                                is otherwise recommended as well if
-                                the process takes a name on the D-Bus
-                                bus.</para>
+                                is otherwise recommended if the process
+                                takes a name on the D-Bus bus.</para>
                                 </listitem>
                         </varlistentry>
 
                                 <term><varname>ExecStart=</varname></term>
                                 <listitem><para>Commands with their
                                 arguments that are executed when this
-                                service is started. The first
-                                argument must be an absolute path
-                                name.</para>
+                                service is started. For each of the
+                                specified commands, the first argument
+                                must be an absolute and literal path
+                                to an executable.</para>
 
                                 <para>When <varname>Type</varname> is
                                 not <option>oneshot</option>, only one
                                 <varname>Type=oneshot</varname> is
                                 used, more than one command may be
                                 specified. Multiple command lines may
-                                be concatenated in a single directive,
+                                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.
+                                once with the same effect.
                                 Lone semicolons may be escaped as
                                 <literal>\;</literal>. If the empty
                                 string is assigned to this option, the
                                 prior assignments of this option will
                                 have no effect.</para>
 
+                                <para>Each command line is split on
+                                whitespace, with the first item being
+                                the command to execute, and the
+                                subsequent items being the arguments.
+                                Double quotes ("...") and single
+                                quotes ('...') may be used, in which
+                                case everything until the next
+                                matching quote becomes part of the
+                                same argument. Quotes themselves are
+                                removed after parsing. In addition, a
+                                trailing backslash
+                                (<literal>\</literal>) may be used to
+                                merge lines. This syntax is intended
+                                to be very similar to shell syntax,
+                                but only the meta-characters and
+                                expansions described in the following
+                                paragraphs are understood.
+                                Specifically, redirection using
+                                <literal>&lt;</literal>,
+                                <literal>&lt;&lt;</literal>,
+                                <literal>&gt;</literal>, and
+                                <literal>&gt;&gt;</literal>, pipes
+                                using <literal>|</literal>, and
+                                running programs in the background
+                                using <literal>&amp;</literal>
+                                and <emphasis>other elements of shell
+                                syntax are not supported</emphasis>.
+                                </para>
+
                                 <para>If more than one command is
                                 specified, the commands are invoked
-                                one by one sequentially in the order
-                                they appear in the unit file. If one
-                                of the commands fails (and is not
-                                prefixed with <literal>-</literal>),
-                                other lines are not executed and the
-                                unit is considered failed.</para>
+                                sequentially in the order they appear
+                                in the unit file. If one of the
+                                commands fails (and is not prefixed
+                                with <literal>-</literal>), other lines
+                                are not executed, and the unit is
+                                considered failed.</para>
 
                                 <para>Unless
                                 <varname>Type=forking</varname> is
                                 <para>The command line accepts
                                 <literal>%</literal> specifiers as
                                 described in
-                                <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>
+                                <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>Basic environment variable
                                 substitution is supported. Use
                                 <literal>${FOO}</literal> as part of a
-                                word, or as a word of its own on the
+                                word, or as a word of its own, on the
                                 command line, in which case it will be
                                 replaced by the value of the
                                 environment variable including all
                                 whitespace it contains, resulting in a
-                                single argument.  Use
+                                single argument. Use
                                 <literal>$FOO</literal> as a separate
                                 word on the command line, in which
                                 case it will be replaced by the value
-                                of the environment variable split up
-                                at whitespace, resulting in zero or
-                                more arguments. To pass a literal dollar sign,
-                                use <literal>$$</literal>. Note that the first
-                                argument (i.e. the program to execute)
-                                may not be a variable, since it must
-                                be a literal and absolute path
-                                name.</para>
+                                of the environment variable split at
+                                whitespace, resulting in zero or more
+                                arguments. To pass a literal dollar
+                                sign, use <literal>$$</literal>.
+                                Variables whose value is not known at
+                                expansion time are treated as empty
+                                strings. Note that the first argument
+                                (i.e. the program to execute) may not
+                                be a variable.</para>
+
+                                <para>Variables to be used in this
+                                fashion may be defined through
+                                <varname>Environment=</varname> and
+                                <varname>EnvironmentFile=</varname>.
+                                In addition, variables listed in the
+                                section "Environment variables in
+                                spawned processes" in
+                                <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                                which are considered "static
+                                configuration", may be used (this includes
+                                e.g. <varname>$USER</varname>, but not
+                                <varname>$TERM</varname>).</para>
 
                                 <para>Optionally, if the absolute file
                                 name is prefixed with
                                 be used, they need to be passed
                                 explicitly to a shell implementation
                                 of some kind. Example:</para>
-                                <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'
-                                </programlisting>
-
-                                <para>For services run by a user
-                                instance of systemd the special
-                                environment variable
-                                <varname>$MANAGERPID</varname> is set
-                                to the PID of the systemd
-                                instance.</para>
-                                </listitem>
+                                <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'</programlisting>
+                                <para>Example:</para>
+                                <programlisting>ExecStart=/bin/echo one ; /bin/echo "two two"</programlisting>
+                                <para>This will execute
+                                <command>/bin/echo</command> two
+                                times, each time with one argument:
+                                <literal>one</literal> and
+                                <literal>two two</literal>,
+                                respectively. Because two commands are
+                                specified,
+                                <varname>Type=oneshot</varname> must
+                                be used.</para>
+
+                                <para>Example:</para>
+                                <programlisting>ExecStart=/bin/echo / &gt;/dev/null &amp; \; \
+/bin/ls</programlisting>
+                                <para>This will execute
+                                <command>/bin/echo</command> with five
+                                arguments: <literal>/</literal>,
+                                <literal>&gt;/dev/null</literal>,
+                                <literal>&amp;</literal>,
+                                <literal>;</literal>, and
+                                <literal>/bin/ls</literal>.</para>
+
+                                <para>Example:</para>
+                                <programlisting>Environment="ONE=one" 'TWO=two two'
+ExecStart=/bin/echo $ONE $TWO ${TWO}</programlisting>
+                                <para>This will execute
+                                <command>/bin/echo</command> with four
+                                arguments: <literal>one</literal>,
+                                <literal>two</literal>,
+                                <literal>two</literal>, and
+                                <literal>two two</literal>.</para>
+                              </listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 here following the same scheme as for
                                 <varname>ExecStart=</varname>.</para>
 
-                                <para>One additional special
-                                environment variables is set: if known
+                                <para>One additional, special
+                                environment variable is set: if known,
                                 <varname>$MAINPID</varname> is set to
                                 the main process of the daemon, and
                                 may be used for command lines like the
                                 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 this option are run are
+                                optional. After the commands configured
+                                in this option are run, all processes
+                                remaining for a service are
                                 terminated according to the
                                 <varname>KillMode=</varname> setting
                                 (see
                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
                                 this option is not specified, the
-                                process is terminated right-away when
+                                process is terminated immediately when
                                 service stop is requested. Specifier
                                 and environment variable substitution
                                 is supported (including
                                 daemon service does not signal
                                 start-up completion within the
                                 configured time, the service will be
-                                considered failed and be shut down
-                                again.
+                                considered failed and will be shut
+                                down again.
                                 Takes a unit-less value in seconds, or a
                                 time span value such as "5min
-                                20s". Pass 0 to disable the timeout
-                                logic. Defaults to <varname>TimeoutStartSec=</varname> in
-                                manager configuration file, except when
-                                <varname>Type=oneshot</varname> is
-                                used in which case the timeout
+                                20s". Pass <literal>0</literal> to
+                                disable the timeout logic. Defaults to
+                                <varname>TimeoutStartSec=</varname> from
+                                the manager configuration file, except
+                                when <varname>Type=oneshot</varname> is
+                                used, in which case the timeout
                                 is disabled by default.
                                 </para></listitem>
                         </varlistentry>
                                 <term><varname>TimeoutStopSec=</varname></term>
                                 <listitem><para>Configures the time to
                                 wait for stop. If a service is asked
-                                to stop but does not terminate in the
+                                to stop, but does not terminate in the
                                 specified time, it will be terminated
-                                forcibly via <constant>SIGTERM</constant>, and after
-                                another delay of this time with
-                                <constant>SIGKILL</constant> (See
+                                forcibly via <constant>SIGTERM</constant>,
+                                and after another timeout of equal duration
+                                with <constant>SIGKILL</constant> (see
                                 <varname>KillMode=</varname>
                                 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
                                 Takes a unit-less value in seconds, or a
                                 time span value such as "5min
-                                20s". Pass 0 to disable the timeout
-                                logic. Defaults to <varname>TimeoutStartSec=</varname> in
+                                20s". Pass <literal>0</literal> to disable
+                                the timeout logic. Defaults to
+                                <varname>TimeoutStartSec=</varname> from the
                                 manager configuration file.
                                 </para></listitem>
                         </varlistentry>
                                 watchdog is activated when the start-up is
                                 completed. The service must call
                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
-                                regularly with "WATCHDOG=1" (i.e. the
-                                "keep-alive ping"). If the time
+                                regularly with <literal>WATCHDOG=1</literal>
+                                (i.e. the "keep-alive ping"). If the time
                                 between two such calls is larger than
                                 the configured time, then the service
-                                is placed in a failure state. By
+                                is placed in a failed state. By
                                 setting <varname>Restart=</varname> to
                                 <option>on-failure</option> or
                                 <option>always</option>, the service
                                 service process exits, is killed,
                                 or a timeout is reached. The service
                                 process may be the main service
-                                process, but also one of the processes
-                                specified with
+                                process, but it may also be one of the
+                                processes specified with
                                 <varname>ExecStartPre=</varname>,
                                 <varname>ExecStartPost=</varname>,
                                 <varname>ExecStopPre=</varname>,
                                 exits cleanly.
                                 In this context, a clean exit means
                                 an exit code of 0, or one of the signals
-                                <constant>SIGHUP</constant>, <constant>SIGINT</constant>, <constant>SIGTERM</constant>, or <constant>SIGPIPE</constant>, and
+                                <constant>SIGHUP</constant>,
+                                <constant>SIGINT</constant>,
+                                <constant>SIGTERM</constant>,
+                                or <constant>SIGPIPE</constant>, and
                                 additionally, exit statuses and signals
                                 specified in <varname>SuccessExitStatus=</varname>.
                                 If set to <option>on-failure</option>,
                                 the service will be restarted when the
-                                process exits with an nonzero exit code,
+                                process exits with a non-zero exit code,
                                 is terminated by a signal (including on
                                 core dump), when an operation (such as
                                 service reload) times out, and when the
                                 timeout for the service expires.
                                 If set to
                                 <option>always</option>, the service
-                                will be restarted regardless whether
+                                will be restarted regardless of whether
                                 it exited cleanly or not, got
-                                terminated abnormally by a signal or
+                                terminated abnormally by a signal, or
                                 hit a timeout.</para>
 
                                 <para>In addition to the above settings,
                                 considered successful termination, in
                                 addition to the normal successful exit
                                 code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
-                                <constant>SIGTERM</constant> and <constant>SIGPIPE</constant>. Exit status
+                                <constant>SIGTERM</constant>, and <constant>SIGPIPE</constant>. Exit status
                                 definitions can either be numeric exit
                                 codes or termination signal names,
-                                separated by spaces. Example:
-                                <literal>SuccessExitStatus=1 2 8
-                                <constant>SIGKILL</constant></literal>, ensures that exit
-                                codes 1, 2, 8 and the termination
-                                signal <constant>SIGKILL</constant> are considered clean
-                                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
+                                separated by spaces. For example:
+                                <programlisting>SuccessExitStatus=1 2 8 <constant>SIGKILL</constant></programlisting>
+                                ensures that exit codes 1, 2, 8 and
+                                the termination signal
+                                <constant>SIGKILL</constant> are
+                                considered clean service terminations.
+                                </para>
+
+                                <para>Note that if a process has a
+                                signal handler installed and exits by
+                                calling
+                                <citerefentry><refentrytitle>_exit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+                                in response to a signal, the
+                                information about the signal is lost.
+                                Programs should instead perform cleanup and kill themselves with the same signal instead. See
+                                <ulink url="http://www.cons.org/cracauer/sigint.html">Proper handling of SIGINT/SIGQUIT — How to be a proper program</ulink>.</para>
+
+                                <para>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>
 
                                 <listitem><para>Takes a list of exit
                                 status definitions that when returned
                                 by the main service process will
-                                prevent automatic service restarts
+                                prevent automatic service restarts,
                                 regardless of the restart setting
                                 configured with
                                 <varname>Restart=</varname>. Exit
                                 numeric exit codes or termination
                                 signal names, and are separated by
                                 spaces. Defaults to the empty list, so
-                                that by default no exit status is
+                                that, by default, no exit status is
                                 excluded from the configured restart
                                 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. This
-                                option may appear more than once in
-                                which case the list of restart preventing
+                                signal <constant>SIGABRT</constant> 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
+                                list is reset and all prior assignments
                                 of this option will have no
                                 effect.</para></listitem>
                         </varlistentry>
                         <varlistentry>
                                 <term><varname>PermissionsStartOnly=</varname></term>
                                 <listitem><para>Takes a boolean
-                                argument. If true, the permission
-                                related execution options as
+                                argument. If true, the permission-related
+                                execution options, as
                                 configured with
                                 <varname>User=</varname> and similar
                                 options (see
                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                                for more information) are only applied
+                                for more information), are only applied
                                 to the process started with
                                 <varname>ExecStart=</varname>, and not
                                 to the various other
                                 <varname>ExecStartPre=</varname>,
                                 <varname>ExecStartPost=</varname>,
                                 <varname>ExecReload=</varname>,
-                                <varname>ExecStop=</varname>,
+                                <varname>ExecStop=</varname>, and
                                 <varname>ExecStopPost=</varname>
                                 commands. If false, the setting is
                                 applied to all configured commands the
                         <varlistentry>
                                 <term><varname>RootDirectoryStartOnly=</varname></term>
                                 <listitem><para>Takes a boolean
-                                argument. If true, the root directory
+                                argument. If true, the root directory,
                                 as configured with the
                                 <varname>RootDirectory=</varname>
                                 option (see
                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                                for more information) is only applied
+                                for more information), is only applied
                                 to the process started with
                                 <varname>ExecStart=</varname>, and not
                                 to the various other
                                 <varname>ExecStartPre=</varname>,
                                 <varname>ExecStartPost=</varname>,
                                 <varname>ExecReload=</varname>,
-                                <varname>ExecStop=</varname>,
+                                <varname>ExecStop=</varname>, and
                                 <varname>ExecStopPost=</varname>
                                 commands. If false, the setting is
                                 applied to all configured commands the
 
                         <varlistentry>
                                 <term><varname>NonBlocking=</varname></term>
-                                <listitem><para>Set O_NONBLOCK flag
+                                <listitem><para>Set the
+                                <constant>O_NONBLOCK</constant> flag
                                 for all file descriptors passed via
                                 socket-based activation. If true, all
                                 file descriptors >= 3 (i.e. all except
-                                STDIN/STDOUT/STDERR) will have
-                                the O_NONBLOCK flag set and hence are in
+                                stdin, stdout, and stderr) will have
+                                the <constant>O_NONBLOCK</constant> flag
+                                set and hence are in
                                 non-blocking mode. This option is only
                                 useful in conjunction with a socket
                                 unit, as described in
                                 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
+                                traffic than that which inherits the
+                                sockets. Or in other words: the
                                 <varname>Service=</varname> setting of
                                 <filename>.socket</filename> units
                                 does not have to match the inverse of
                                 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
+                                sockets is reset, and all prior uses of
                                 this setting will have no
                                 effect.</para></listitem>
                         </varlistentry>
 
                                 <listitem><para>Configure service
                                 start rate limiting. By default,
-                                services which are started more often
-                                than 5 times within 10s are not
+                                services which are started more
+                                than 5 times within 10 seconds are not
                                 permitted to start any more times
-                                until the 10s interval ends. With
+                                until the 10 second interval ends. With
                                 these two options, this rate limiting
                                 may be modified. Use
                                 <varname>StartLimitInterval=</varname>
-                                to configure the checking interval
-                                (defaults to 10s, set to 0 to disable
+                                to configure the checking interval (defaults to
+                                <varname>DefaultStartLimitInterval=</varname> in
+                                manager configuration file, set to 0 to disable
                                 any kind of rate limiting). Use
                                 <varname>StartLimitBurst=</varname> to
                                 configure how many starts per interval
-                                are allowed (defaults to 5). These
+                                are allowed (defaults to
+                                <varname>DefaultStartLimitBurst=</varname> in
+                                manager configuration file). These
                                 configuration options are particularly
                                 useful in conjunction with
-                                <varname>Restart=</varname>, however
-                                apply to all kinds of starts
+                                <varname>Restart=</varname>; however,
+                                they apply to all kinds of starts
                                 (including manual), not just those
                                 triggered by the
                                 <varname>Restart=</varname> logic.
                                 Note that units which are configured
                                 for <varname>Restart=</varname> and
                                 which reach the start limit are not
-                                attempted to be restarted anymore,
-                                however they may still be restarted
-                                manually at a later point from which
-                                point on the restart logic is again
+                                attempted to be restarted anymore;
+                                however, they may still be restarted
+                                manually at a later point, from which
+                                point on, the restart logic is again
                                 activated. Note that
                                 <command>systemctl
                                 reset-failed</command> will cause the
                                 hit. Takes one of
                                 <option>none</option>,
                                 <option>reboot</option>,
-                                <option>reboot-force</option> or
+                                <option>reboot-force</option>, or
                                 <option>reboot-immediate</option>. If
                                 <option>none</option> is set,
                                 hitting the rate limit will trigger no
                                 action besides that the start will not
-                                be
-                                permitted. <option>reboot</option>
+                                be permitted. <option>reboot</option>
                                 causes a reboot following the normal
                                 shutdown procedure (i.e. equivalent to
-                                <command>systemctl reboot</command>),
+                                <command>systemctl reboot</command>).
                                 <option>reboot-force</option> causes
-                                an forced reboot which will terminate
+                                a forced reboot which will terminate
                                 all processes forcibly but should
                                 cause no dirty file systems on reboot
                                 (i.e. equivalent to <command>systemctl
                                 causes immediate execution of the
                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
                                 system call, which might result in
-                                data loss.  Defaults to
+                                data loss. Defaults to
                                 <option>none</option>.</para></listitem>
                         </varlistentry>
 
                                 in relation to SysV services lacking
                                 LSB headers. This option is only
                                 necessary to fix ordering in relation
-                                to legacy SysV services, that have no
+                                to legacy SysV services that have no
                                 ordering information encoded in the
-                                script headers. As such it should only
-                                be used as temporary compatibility
-                                option, and not be used in new unit
-                                files. Almost always it is a better
+                                script headers. As such, it should only
+                                be used as temporary compatibility
+                                option and should not be used in new unit
+                                files. Almost always, it is a better
                                 choice to add explicit ordering
                                 directives via
                                 <varname>After=</varname> or
                                 <varname>Before=</varname>,
-                                instead. For more details see
-                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
-                                used, pass an integer value in the
+                                instead. For more details, see
+                                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+                                If used, pass an integer value in the
                                 range 0-99.</para></listitem>
                         </varlistentry>
-
                 </variablelist>
         </refsect1>