which configure resource control settings for the processes of the
service.</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. Note that this
- compatibility is quite comprehensive but not 100%. For details
- about the incompatibilities, see the <ulink
- url="https://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
- with SysV</ulink> document.</para>
+ <para>If SysV init compat is enabled, systemd automatically creates service units that wrap SysV init
+ scripts (the service name is the same as the name of the script, with a <literal>.service</literal>
+ suffix added); see
+ <citerefentry><refentrytitle>systemd-sysv-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
+ </para>
<para>The <citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>
command allows creating <filename>.service</filename> and <filename>.scope</filename> units dynamically
<refsect1>
<title>Options</title>
- <para>Service files must include a [Service]
+ <para>Service unit files may include [Unit] and [Install] sections, which are described in
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+ </para>
+
+ <para>Service unit 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
will remove the file after the service has shut down if it still exists. The PID file does not need to be owned
by a privileged user, but if it is owned by an unprivileged user additional safety restrictions are enforced:
the file may not be a symlink to a file owned by a different user (neither directly nor indirectly), and the
- PID file must refer to a process already belonging to the service.</para></listitem>
+ PID file must refer to a process already belonging to the service.</para>
+
+ <para>Note that PID files should be avoided in modern projects. Use <option>Type=notify</option> or
+ <option>Type=simple</option> where possible, which does not require use of PID files to determine the
+ main process of a service and avoids needless forking.</para></listitem>
</varlistentry>
<varlistentry>
If set to <option>no</option> (the default), the service will
not be restarted. If set to <option>on-success</option>, it
will be restarted only when the service process 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
- additionally, exit statuses and signals specified in
- <varname>SuccessExitStatus=</varname>. If set to
+ In this context, a clean exit means any of the following:
+ <itemizedlist>
+ <listitem><simpara>exit code of 0;</simpara></listitem>
+ <listitem><simpara>for types other than
+ <varname>Type=oneshot</varname>, one of the signals
+ <constant>SIGHUP</constant>,
+ <constant>SIGINT</constant>,
+ <constant>SIGTERM</constant>, or
+ <constant>SIGPIPE</constant>;</simpara></listitem>
+ <listitem><simpara>exit statuses and signals specified in
+ <varname>SuccessExitStatus=</varname>.</simpara></listitem>
+ </itemizedlist>
+ If set to
<option>on-failure</option>, the service will be restarted
when the process exits with a non-zero exit code, is
terminated by a signal (including on core dump, but excluding
abnormally by a signal, or hit a timeout.</para>
<table>
- <title>Exit causes and the effect of the <varname>Restart=</varname> settings on them</title>
+ <title>Exit causes and the effect of the <varname>Restart=</varname> settings</title>
<tgroup cols='2'>
<colspec colname='path' />
<listitem><para>Takes a list of exit status definitions that, when returned by the main service
process, will be considered successful termination, in addition to the normal successful exit status
- 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
+ 0 and, except for <varname>Type=oneshot</varname>, the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
<constant>SIGTERM</constant>, and <constant>SIGPIPE</constant>. Exit status definitions can be
numeric termination statuses, termination status names, or termination signal names, separated by
spaces. See the Process Exit Codes section in
</variablelist>
- <para>Check
- <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- and
- <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for more settings.</para>
-
+ <para id='shared-unit-options'>Check
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, and
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more
+ settings.</para>
</refsect1>
<refsect1>
<varname>ExecStop=</varname>, and
<varname>ExecStopPost=</varname> options.</para>
- <para>Multiple command lines may be concatenated in a single
- directive by separating them with semicolons (these semicolons
- must be passed as separate words). Lone semicolons may be escaped
- as <literal>\;</literal>.</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 to wrap a whole item (the opening quote may appear only at the beginning or
- after whitespace that is not quoted, and the closing quote must be followed by whitespace or the
- end of line), in which case everything until the next matching quote becomes part of the same
- argument. Quotes themselves are removed. C-style escapes are also supported. The table below
- contains the list of known escape patterns. Only escape patterns which match the syntax in the
- table are allowed; other patterns may be added in the future and unknown patterns will result in
- a warning. In particular, any backslashes should be doubled. Finally, a trailing backslash
- (<literal>\</literal>) may be used to merge lines.</para>
+ <para>Multiple command lines may be concatenated in a single directive by separating them with semicolons
+ (these semicolons must be passed as separate words). Lone semicolons may be escaped as
+ <literal>\;</literal>.</para>
+
+ <para>Each command line is unquoted using the rules described in "Quoting" section in
+ <citerefentry><refentrytitle>systemd.syntax</refentrytitle><manvolnum>7</manvolnum></citerefentry>. The
+ first item becomes the command to execute, and the subsequent items the arguments.</para>
<para>This syntax is inspired by shell syntax, but only the meta-characters and expansions
described in the following paragraphs are understood, and the expansion of variables is
<literal>>/dev/null</literal>,
<literal>&</literal>, <literal>;</literal>, and
<literal>ls</literal>.</para>
-
- <table>
- <title>C escapes supported in command lines and environment variables</title>
- <tgroup cols='2'>
- <colspec colname='escape' />
- <colspec colname='meaning' />
- <thead>
- <row>
- <entry>Literal</entry>
- <entry>Actual value</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry><literal>\a</literal></entry>
- <entry>bell</entry>
- </row>
- <row>
- <entry><literal>\b</literal></entry>
- <entry>backspace</entry>
- </row>
- <row>
- <entry><literal>\f</literal></entry>
- <entry>form feed</entry>
- </row>
- <row>
- <entry><literal>\n</literal></entry>
- <entry>newline</entry>
- </row>
- <row>
- <entry><literal>\r</literal></entry>
- <entry>carriage return</entry>
- </row>
- <row>
- <entry><literal>\t</literal></entry>
- <entry>tab</entry>
- </row>
- <row>
- <entry><literal>\v</literal></entry>
- <entry>vertical tab</entry>
- </row>
- <row>
- <entry><literal>\\</literal></entry>
- <entry>backslash</entry>
- </row>
- <row>
- <entry><literal>\"</literal></entry>
- <entry>double quotation mark</entry>
- </row>
- <row>
- <entry><literal>\'</literal></entry>
- <entry>single quotation mark</entry>
- </row>
- <row>
- <entry><literal>\s</literal></entry>
- <entry>space</entry>
- </row>
- <row>
- <entry><literal>\x<replaceable>xx</replaceable></literal></entry>
- <entry>character number <replaceable>xx</replaceable> in hexadecimal encoding</entry>
- </row>
- <row>
- <entry><literal>\<replaceable>nnn</replaceable></literal></entry>
- <entry>character number <replaceable>nnn</replaceable> in octal encoding</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
</refsect1>
<refsect1>
projects / thirdparty / systemd.git / blobdiff