1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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6 This file is part of systemd.
8 Copyright 2010 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id="systemd">
27 <title>systemd</title>
28 <productname>systemd</productname>
32 <contrib>Developer</contrib>
33 <firstname>Lennart</firstname>
34 <surname>Poettering</surname>
35 <email>lennart@poettering.net</email>
41 <refentrytitle>systemd</refentrytitle>
42 <manvolnum>1</manvolnum>
46 <refname>systemd</refname>
47 <refname>init</refname>
48 <refpurpose>systemd System and Session Manager</refpurpose>
53 <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command>
56 <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
61 <title>Description</title>
63 <para>systemd is a system and session manager for
64 Linux operating systems. When run as first process on
65 boot (as PID 1), it acts as init system that brings
66 up and maintains userspace services.</para>
68 <para>For compatibility with SysV, if systemd is called
69 as <command>init</command> and a PID that is not
70 1, it will execute <command>telinit</command> and pass
71 all command line arguments unmodified. That means
72 <command>init</command> and <command>telinit</command>
73 are mostly equivalent when invoked from normal login sessions. See
74 <citerefentry><refentrytitle>telinit</refentrytitle><manvolnum>8</manvolnum></citerefentry>
75 for more information.</para>
77 <para>When run as system instance, systemd interprets
78 the configuration file
79 <filename>system.conf</filename>, otherwise
80 <filename>session.conf</filename>. See
81 <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
82 for more information.</para>
86 <title>Options</title>
88 <para>The following options are understood:</para>
92 <term><option>-h</option></term>
93 <term><option>--help</option></term>
95 <listitem><para>Prints a short help
96 text and exits.</para></listitem>
99 <term><option>--test</option></term>
101 <listitem><para>Determine startup
102 sequence, dump it and exit. This is an
103 option useful for debugging
104 only.</para></listitem>
107 <term><option>--dump-configuration-items</option></term>
109 <listitem><para>Dump understood unit
110 configuration items. This outputs a
111 terse but complete list of
112 configuration items understood in unit
113 definition files.</para></listitem>
116 <term><option>--introspect=</option></term>
118 <listitem><para>Extract D-Bus
119 interface introspection data. This is
120 mostly useful at install time
121 to generate data suitable for the
123 repository. Optionally the interface
124 name for the introspection data may be
125 specified. If omitted, the
126 introspection data for all interfaces
127 is dumped.</para></listitem>
130 <term><option>--unit=</option></term>
132 <listitem><para>Set default unit to
133 activate on startup. If not specified
135 <filename>default.target</filename>.</para></listitem>
138 <term><option>--system</option></term>
139 <term><option>--session</option></term>
141 <listitem><para>Tell systemd to run a
142 system instance (resp. session
143 instance), even if the process ID is
144 not 1 (resp. is 1), i.e. system is not
145 (resp. is) run as init process.
146 Normally it should not be necessary to
147 pass these options, as systemd
148 automatically detects the mode it is
149 started in. These options are hence of
150 little use except for
151 debugging.</para></listitem>
154 <term><option>--dump-core</option></term>
156 <listitem><para>Dump core on crash. This switch has no effect when run as session instance.</para></listitem>
159 <term><option>--crash-shell</option></term>
161 <listitem><para>Run shell on crash. This switch has no effect when run as session instance.</para></listitem>
164 <term><option>--confirm-spawn</option></term>
166 <listitem><para>Ask for confirmation when spawning processes. This switch has no effect when run as session instance.</para></listitem>
169 <term><option>--show-status</option></term>
171 <listitem><para>Show terse service status information while booting. This switch has no effect when run as session instance.</para></listitem>
174 <term><option>--log-target=</option></term>
176 <listitem><para>Set log
177 target. Argument must be one of
178 <option>console</option>,
179 <option>syslog</option>,
180 <option>kmsg</option>,
181 <option>syslog-or-kmsg</option>,
182 <option>null</option>.</para></listitem>
185 <term><option>--log-level=</option></term>
187 <listitem><para>Set log level. As
188 argument this accepts a numerical log
189 level or the well-known <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
190 symbolic names (lowercase):
191 <option>emerg</option>,
192 <option>alert</option>,
193 <option>crit</option>,
194 <option>err</option>,
195 <option>warning</option>,
196 <option>notice</option>,
197 <option>info</option>,
198 <option>debug</option>.</para></listitem>
201 <term><option>--log-color=</option></term>
203 <listitem><para>Highlight important
204 log messages. Argument is a boolean
205 value. If the argument is omitted it
207 <option>true</option>.</para></listitem>
210 <term><option>--log-location=</option></term>
212 <listitem><para>Include code location
213 in log messages. This is mostly
214 relevant for debugging
215 purposes. Argument is a boolean
216 value. If the argument is omitted
218 <option>true</option>.</para></listitem>
224 <title>Concepts</title>
226 <para>systemd provides a dependency system between
227 various entities called "units". Units encapsulate
228 various objects that are relevant for system boot-up
229 and maintainance. The majority of units are configured
230 in unit configuration files, whose syntax and basic
231 set of options is described in
232 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
233 however some are created automatically from other
234 configuration or dynamically from system state. Units
235 may be active (meaning started, bound, plugged in, ...
236 depending on the unit type), or inactive (meaning
237 stopped, unbound, unplugged, ...), as well as in the
238 process of being activated or deactivated,
239 i.e. between the two states. The following unit types
240 are available:</para>
243 <listitem><para>Service units, which control
244 daemons and the processes they consist of. For
246 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
248 <listitem><para>Socket units, which
249 encapsulate local IPC or network sockets in
250 the system, useful for socket-based
251 activation. For details about socket units see
252 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
253 for details on socket-based activation and
254 other forms of activation, see
255 <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem>
257 <listitem><para>Target units are useful to
258 group units, or provide well-known
259 synchronization points during boot-up, see
260 <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
262 <listitem><para>Device units expose kernel
263 devices in systemd and may be used to
264 implement device-based activation. For details
266 <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
268 <listitem><para>Mount units control mount
269 points in the file system, for details see
270 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
272 <listitem><para>Automount units provide
273 automount capabilities, for on-demand mounting
274 of file systems as well as parallelized
276 <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
278 <listitem><para>Snapshot units can be used to
279 temporarily save the state of the set of
280 systemd units, which later may be restored by
281 activating the saved snapshot unit. For more
283 <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
285 <listitem><para>Timer units are useful for
286 triggering activation of other units based on
287 timers. You may find details in
288 <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
290 <listitem><para>Swap units are very similar to
291 mount units and encapsulated memory swap
292 partitions or files of the operating
293 systemd. They are described in <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
295 <listitem><para>Path units may be used
296 to activate other services when file system
297 objects change or are modified. See
298 <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
302 <para>Units are named as their configuration
303 files. Some units have special semantics. A detailed
305 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
307 <para>On boot systemd activates the target unit
308 <filename>default.target</filename> whose job is to
309 activate on-boot services and other on-boot units by
310 pulling them in via dependencies. Usually the unit
311 name is just an alias (symlink) for either
312 <filename>graphical.target</filename> (for
313 fully-featured boots into the UI) or
314 <filename>multi-user.target</filename> (for limited
315 console-only boots for use in embedded or server
316 environments, or similar; a subset of
317 graphical.target). However it is at the discretion of
318 the administrator to configure it as an alias to any
319 other target unit. See
320 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
321 for details about these target units.</para>
323 <para>Processes systemd spawns are placed in
324 individual Linux control groups named after the unit
325 which they belong to in the private systemd
326 hierarchy. (see <ulink
327 url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>
328 for more information about control groups, or short
329 "cgroups"). systemd uses this to effectively keep
330 track of processes. Control group information is
331 maintained in the kernel, and is accessible via the
332 file system hierarchy (beneath
333 <filename>/cgroup/systemd/</filename>), or in tools
335 <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>
336 (<command>ps xawf -eo pid,user,cgroup,args</command>
337 is particularly useful to list all processes and the
338 systemd units they belong to.).</para>
340 <para>systemd is compatible with the SysV init system
341 to a large degree: SysV init scripts are supported and
342 simply read as an alternative (though limited)
343 configuration file format. The SysV
344 <filename>/dev/initctl</filename> interface is
345 provided, and compatibility implementations of the
346 various SysV client tools are available. In addition to
347 that, various established Unix functionality such as
348 <filename>/etc/fstab</filename> or the
349 <filename>utmp</filename> database are
352 <para>systemd has a minimal transaction system: if a
353 unit is requested to start up or shut down it will add
354 it and all its dependencies to a temporary
355 transaction. Then, it will verify if the transaction
356 is consistent (i.e. whether the ordering of all units
357 is cycle-free). If it is not, systemd will try to fix
358 it up, and removes non-essential jobs from the
359 transaction that might remove the loop. Also, systemd
360 tries to suppress non-essential jobs in the
361 transaction that would stop a running service. Finally
362 it is checked whether the jobs of the transaction
363 contradict jobs that have already been queued, and
364 optionally the transaction is aborted then. If all
365 worked out and the transaction is consistent and
366 minimized in its impact it is merged with all already
367 outstanding jobs and added to the run
368 queue. Effectively this means that before executing a
369 requested operation, systemd will verify that it makes
370 sense, fixing it if possible, and only failing if it
371 really cannot work.</para>
373 <para>Systemd contains native implementations of
374 various tasks that need to be executed as part of the
375 boot process. For example, it sets the host name or
376 configures the loopback network device. It also sets
377 up and mounts various API file systems, such as
378 <filename>/sys</filename> or
379 <filename>/proc</filename>.</para>
381 <para>For more information about the concepts and
382 ideas behind systemd please refer to the <ulink
383 url="http://0pointer.de/blog/projects/systemd.html">Original
384 Design Document</ulink>.</para>
388 <title>Directories</title>
392 <term>System unit directories</term>
394 <listitem><para>The systemd system
395 manager reads unit configuration from
396 various directories. Packages that
397 want to install unit files shall place
398 them in the directory returned by
399 <command>pkg-config systemd
400 --variable=systemdsystemunitdir</command>. Other
401 directories checked are
402 <filename>/usr/local/share/systemd/system</filename>
404 <filename>/usr/share/systemd/system</filename>. User
405 configuration always takes
406 precedence. <command>pkg-config
408 --variable=systemdsystemconfdir</command>
409 returns the path of the system
410 configuration directory. Packages
411 should alter the content of these directories
413 <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>
414 tool.</para></listitem>
420 <term>Session unit directories</term>
422 <listitem><para>Similar rules apply
424 directories. However, here the <ulink
425 url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
426 Base Directory specification</ulink>
428 units. Applications should place their
429 unit files in the directory returned
430 by <command>pkg-config systemd
431 --variable=systemdsessionunitdir</command>. Global
432 configuration is done in the
433 directory reported by
434 <command>pkg-config systemd
435 --variable=systemdsessionconfdir</command>. The
436 <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>
437 tool can handle both global (i.e. for
438 all users) and private (for one user)
439 enabling/disabling of
440 units.</para></listitem>
446 <term>SysV init scripts directory</term>
448 <listitem><para>The location of the
449 SysV init script directory varies
450 between distributions. If systemd
451 cannot find a native unit file for a
452 requested service, it will look for a
453 SysV init script of the same name
455 <filename>.service</filename> suffix
456 removed).</para></listitem>
462 <term>SysV runlevel link farm directory</term>
464 <listitem><para>The location of the
465 SysV runlevel link farm directory
466 varies between distributions. systemd
467 will take the link farm into account
468 when figuring out whether a service
469 shall be enabled. Note that a service
470 unit with a native unit configuration
471 file cannot be started by activating it
472 in the SysV runlevel link
473 farm.</para></listitem>
479 <title>Signals</title>
485 <listitem><para>Upon receiving this
486 signal the systemd system manager
487 serializes its state, reexecutes
488 itself and deserializes the saved
489 state again. This is mostly equivalent
490 to <command>systemctl
491 daemon-reexec</command>.</para>
493 <para>systemd session managers will
495 <filename>exit.target</filename> unit
496 when this signal is received. This is
498 <command>systemctl --session start
499 exit.target</command>.</para></listitem>
505 <listitem><para>Upon receiving this
506 signal the systemd system manager will
508 <filename>ctrl-alt-del.target</filename> unit. This
509 is mostly equivalent to
510 <command>systemctl start
511 ctl-alt-del.target</command>.</para>
513 <para>systemd session managers
514 treat this signal the same way as
515 SIGTERM.</para></listitem>
519 <term>SIGWINCH</term>
521 <listitem><para>When this signal is
522 received the systemd system manager
524 <filename>kbrequest.target</filename>
525 unit. This is mostly equivalent to
526 <command>systemctl start
527 kbrequest.target</command>.</para>
529 <para>This signal is ignored by
531 managers.</para></listitem>
537 <listitem><para>When this signal is
538 received the systemd manager
540 <filename>sigpwr.target</filename>
541 unit. This is mostly equivalent to
542 <command>systemctl start
543 sigpwr.target</command>.</para></listitem>
549 <listitem><para>When this signal is
550 received the systemd manager will try
551 to reconnect to the D-Bus
552 bus.</para></listitem>
558 <listitem><para>When this signal is
559 received the systemd manager will log
560 its complete state in human readable
561 form. The data logged is the same as
562 printed by <command>systemctl
563 dump</command>.</para></listitem>
569 <listitem><para>Reloads the complete
570 daemon configuration. This is mostly
571 equivalent to <command>systemctl
572 daemon-reload</command>.</para></listitem>
576 <term>SIGRTMIN+0</term>
578 <listitem><para>Enters default mode, starts the
579 <filename>default.target</filename>
580 unit. This is mostly equivalent to
581 <command>systemctl start
582 default.target</command>.</para></listitem>
586 <term>SIGRTMIN+1</term>
588 <listitem><para>Enters rescue mode,
590 <filename>rescue.target</filename>
591 unit. This is mostly equivalent to
592 <command>systemctl isolate
593 rescue.target</command>.</para></listitem>
597 <term>SIGRTMIN+2</term>
599 <listitem><para>Enters emergency mode,
601 <filename>emergency.service</filename>
602 unit. This is mostly equivalent to
603 <command>systemctl isolate
604 emergency.service</command>.</para></listitem>
608 <term>SIGRTMIN+3</term>
610 <listitem><para>Halts the machine,
612 <filename>halt.target</filename>
613 unit. This is mostly equivalent to
614 <command>systemctl start
615 halt.target</command>.</para></listitem>
619 <term>SIGRTMIN+4</term>
621 <listitem><para>Powers off the machine,
623 <filename>poweroff.target</filename>
624 unit. This is mostly equivalent to
625 <command>systemctl start
626 poweroff.target</command>.</para></listitem>
630 <term>SIGRTMIN+5</term>
632 <listitem><para>Reboots the machine,
634 <filename>reboot.target</filename>
635 unit. This is mostly equivalent to
636 <command>systemctl start
637 reboot.target</command>.</para></listitem>
643 <title>Environment</title>
647 <term><varname>$SYSTEMD_LOG_LEVEL</varname></term>
648 <listitem><para>systemd reads the
649 log level from this environment
650 variable. This can be overridden with
651 <option>--log-level=</option>.</para></listitem>
655 <term><varname>$SYSTEMD_LOG_TARGET</varname></term>
656 <listitem><para>systemd reads the
657 log target from this environment
658 variable. This can be overridden with
659 <option>--log-target=</option>.</para></listitem>
663 <term><varname>$SYSTEMD_LOG_COLOR</varname></term>
664 <listitem><para>Controls whether
665 systemd highlights important log
666 messages. This can be overridden with
667 <option>--log-color=</option>.</para></listitem>
671 <term><varname>$SYSTEMD_LOG_LOCATION</varname></term>
672 <listitem><para>Controls whether
673 systemd prints the code location along
674 with log messages. This can be
676 <option>--log-location=</option>.</para></listitem>
680 <term><varname>$XDG_CONFIG_HOME</varname></term>
681 <term><varname>$XDG_CONFIG_DIRS</varname></term>
682 <term><varname>$XDG_DATA_HOME</varname></term>
683 <term><varname>$XDG_DATA_DIRS</varname></term>
685 <listitem><para>The systemd session
686 manager uses these variables in
687 accordance to the <ulink
688 url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
689 Base Directory specification</ulink>
690 to find its configuration.</para></listitem>
694 <term><varname>$SYSTEMD_UNIT_PATH</varname></term>
696 <listitem><para>Controls where systemd
698 files.</para></listitem>
702 <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term>
704 <listitem><para>Controls where systemd
705 looks for SysV init scripts.</para></listitem>
709 <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term>
711 <listitem><para>Controls where systemd
712 looks for SysV init script runlevel link
713 farms.</para></listitem>
717 <term><varname>$LISTEN_PID</varname></term>
718 <term><varname>$LISTEN_FDS</varname></term>
720 <listitem><para>Set by systemd for
721 supervised processes during
722 socket-based activation. See
723 <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
724 for more information.
729 <term><varname>$NOTIFY_SOCKET</varname></term>
731 <listitem><para>Set by systemd for
732 supervised processes for status and
733 start-up completion notification. See
734 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
735 for more information.
742 <title>Kernel Command Line</title>
744 <para>When run as system instance systemd parses a few kernel command line arguments:</para>
748 <term><varname>systemd.unit=</varname></term>
750 <listitem><para>Overrides the unit to
751 activate on boot. Defaults to
752 <filename>default.target</filename>. This
753 may be used to temporarily boot into a
754 different boot unit, for example
755 <filename>rescue.target</filename> or
756 <filename>emergency.service</filename>. See
757 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
758 for details about these
759 units.</para></listitem>
763 <term><varname>systemd.log_target=</varname></term>
764 <term><varname>systemd.log_level=</varname></term>
765 <term><varname>systemd.log_color=</varname></term>
766 <term><varname>systemd.log_location=</varname></term>
768 <listitem><para>Controls log output,
769 with the same effect as the
770 <varname>$SYSTEMD_LOG_TARGET</varname>, <varname>$SYSTEMD_LOG_LEVEL</varname>, <varname>$SYSTEMD_LOG_COLOR</varname>, <varname>$SYSTEMD_LOG_LOCATION</varname>
771 environment variables described above.</para></listitem>
775 <term><varname>systemd.dump_core=</varname></term>
777 <listitem><para>Takes a boolean
778 argument. If <option>true</option>
779 systemd dumps core when it
780 crashes. Otherwise no core dump is
782 <option>true</option>.</para></listitem>
786 <term><varname>systemd.crash_shell=</varname></term>
788 <listitem><para>Takes a boolean
789 argument. If <option>true</option>
790 systemd spawns a shell when it
791 crashes. Otherwise no core dump is
793 <option>false</option>, for security
794 reasons, as the shell is not protected
796 authentication.</para></listitem>
800 <term><varname>systemd.crash_chvt=</varname></term>
802 <listitem><para>Takes an integer
803 argument. If positive systemd
804 activates the specified virtual
805 terminal when it crashes. Defaults to
806 <literal>-1</literal>.</para></listitem>
810 <term><varname>systemd.show_status=</varname></term>
812 <listitem><para>Takes a boolean
813 argument. If <option>true</option>
814 shows terse service status updates on
815 the console during bootup. Defaults to
816 <option>true</option>.</para></listitem>
823 <title>Sockets and FIFOs</title>
827 <term><filename>@/org/freedesktop/systemd1/notify</filename></term>
829 <listitem><para>Daemon status
830 notification socket. This is an AF_UNIX
831 datagram socket in the Linux abstract
832 namespace, and is used to implement
833 the daemon notification logic as
835 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
840 <term><filename>@/org/freedesktop/systemd1/logger</filename></term>
842 <listitem><para>Used internally by the
843 <filename>systemd-logger.service</filename>
844 unit to connect STDOUT and/or STDERR
845 of spawned processes to
846 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
847 or the kernel log buffer. This is an
848 AF_UNIX stream socket in the Linux
849 abstract namespace.</para></listitem>
853 <term><filename>@/org/freedesktop/systemd1/private</filename></term>
855 <listitem><para>Used internally as
856 communication channel between
857 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
858 and the systemd process. This is an
859 AF_UNIX stream socket in the Linux
860 abstract namespace. This interface is
861 private to systemd and should not be
863 projects.</para></listitem>
867 <term><filename>/dev/initctl</filename></term>
869 <listitem><para>Limited compatibility
870 support for the SysV client interface,
871 as implemented by the
872 <filename>systemd-initctl.service</filename>
873 unit. This is a named pipe in the file
874 system. This interface is obsolete and
875 should not be used in new
876 applications.</para></listitem>
882 <title>See Also</title>
884 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
885 <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
886 <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
887 <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
888 <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
889 <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
890 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
891 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
892 <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>