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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="systemctl">
27 <title>systemctl</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>systemctl</refentrytitle>
42 <manvolnum>1</manvolnum>
46 <refname>systemctl</refname>
47 <refpurpose>Control the systemd system and service manager</refpurpose>
52 <command>systemctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg> <arg choice="opt" rep="repeat">NAME</arg></command>
57 <title>Description</title>
59 <para><command>systemctl</command> may be used to
60 introspect and control the state of the
61 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
62 system and service manager.</para>
66 <title>Options</title>
68 <para>The following options are understood:</para>
72 <term><option>--help</option></term>
73 <term><option>-h</option></term>
75 <listitem><para>Prints a short help
76 text and exits.</para></listitem>
80 <term><option>--version</option></term>
82 <listitem><para>Prints a short version
83 string and exits.</para></listitem>
87 <term><option>--type=</option></term>
88 <term><option>-t</option></term>
90 <listitem><para>When listing units,
91 limit display to certain unit
92 types. If not specified units of all
93 types will be shown. The argument
94 should be a unit type name such as
95 <option>service</option>,
96 <option>socket</option> and
97 similar.</para></listitem>
101 <term><option>--property=</option></term>
102 <term><option>-p</option></term>
104 <listitem><para>When showing
105 unit/job/manager information, limit
106 display to certain properties as
107 specified as argument. If not
108 specified all set properties are
109 shown. The argument should be a
110 property name, such as
111 <literal>MainPID</literal>. If
112 specified more than once all
113 properties with the specified names
114 are shown.</para></listitem>
118 <term><option>--all</option></term>
119 <term><option>-a</option></term>
121 <listitem><para>When listing units,
122 show all units, regardless of their
123 state, including inactive units. When
124 showing unit/job/manager information,
125 show all properties regardless whether
126 they are set or not.</para></listitem>
130 <term><option>--failed</option></term>
132 <listitem><para>When listing units,
133 show only failed units. Do not confuse
135 <option>--fail</option>.</para></listitem>
139 <term><option>--full</option></term>
141 <listitem><para>Do not ellipsize unit
142 names and truncate unit descriptions
144 <command>list-units</command> and
145 <command>list-jobs</command>.</para></listitem>
149 <term><option>--fail</option></term>
151 <listitem><para>If the requested
152 operation conflicts with a pending
153 unfinished job, fail the command. If
154 this is not specified the requested
155 operation will replace the pending job,
156 if necessary. Do not confuse
158 <option>--failed</option>.</para></listitem>
162 <term><option>--ignore-dependencies</option></term>
164 <listitem><para>When enqueuing a new
165 job ignore all its dependencies and
166 execute it immediately. If passed no
167 required units of the unit passed will
168 be pulled in, and no ordering
169 dependencies will be honoured. This is
170 mostly a debugging and rescue tool for
171 the administrator and should not be
173 applications.</para></listitem>
177 <term><option>--quiet</option></term>
178 <term><option>-q</option></term>
180 <listitem><para>Suppress output to
182 <command>snapshot</command>,
183 <command>is-active</command>,
184 <command>enable</command> and
185 <command>disable</command>.</para></listitem>
189 <term><option>--no-block</option></term>
191 <listitem><para>Do not synchronously wait for
192 the requested operation to finish. If this is
193 not specified the job will be verified,
194 enqueued and <command>systemctl</command> will
195 wait until it is completed. By passing this
196 argument it is only verified and
197 enqueued.</para></listitem> </varlistentry>
200 <term><option>--no-pager</option></term>
202 <listitem><para>Do not pipe output into a
203 pager.</para></listitem>
207 <term><option>--system</option></term>
209 <listitem><para>Talk to the systemd
210 system manager. (Default)</para></listitem>
214 <term><option>--user</option></term>
216 <listitem><para>Talk to the systemd
217 manager of the calling user.</para></listitem>
221 <term><option>--order</option></term>
222 <term><option>--require</option></term>
224 <listitem><para>When used in
226 <command>dot</command> command (see
227 below), selects which dependencies are
228 shown in the dependency graph. If
229 <option>--order</option> is passed
230 only dependencies of type
231 <varname>After=</varname> or
232 <varname>Before=</varname> are
233 shown. If <option>--require</option>
234 is passed only dependencies of type
235 <varname>Requires=</varname>,
236 <varname>RequiresOverridable=</varname>,
237 <varname>Requisite=</varname>,
238 <varname>RequisiteOverridable=</varname>,
239 <varname>Wants=</varname> and
240 <varname>Conflicts=</varname> are
241 shown. If neither is passed, shows
242 dependencies of all these
243 types.</para></listitem>
247 <term><option>--no-wall</option></term>
249 <listitem><para>Don't send wall
251 halt, power-off, reboot.</para></listitem>
255 <term><option>--global</option></term>
257 <listitem><para>When used with
258 <command>enable</command> and
259 <command>disable</command>, operate on the
260 global user configuration
261 directory, thus enabling or disabling
262 a unit file globally for all future
263 logins of all users.</para></listitem>
267 <term><option>--no-reload</option></term>
269 <listitem><para>When used with
270 <command>enable</command> and
271 <command>disable</command>, do not
272 implicitly reload daemon configuration
274 changes.</para></listitem>
278 <term><option>--no-ask-password</option></term>
280 <listitem><para>When used with
281 <command>start</command> and related
282 commands, disables asking for
283 passwords. Background services may
284 require input of a password or
285 passphrase string, for example to
286 unlock system hard disks or
287 cryptographic certificates. Unless
288 this option is specified and the
289 command is invoked from a terminal
290 <command>systemctl</command> will
291 query the user on the terminal for the
292 necessary secrets. Use this option to
293 switch this behavior off. In this
294 case the password must be supplied by
295 some other means (for example
296 graphical password agents) or the
297 service might fail.</para></listitem>
301 <term><option>--kill-mode=</option></term>
303 <listitem><para>When used with
304 <command>kill</command>, choose the
305 mode how to kill the selected
306 processes. Must be one of
307 <option>control-group</option> or
308 <option>process</option> to select
309 whether to kill the entire control
310 group or only the selected process
311 itself. If omitted defaults to
312 <option>control-group</option> if
313 <option>--kill-who=all</option> is
314 set, or <option>process</option>
315 otherwise. You probably never need to
316 use this switch.</para></listitem>
320 <term><option>--kill-who=</option></term>
322 <listitem><para>When used with
323 <command>kill</command>, choose which
324 processes to kill. Must be one of
325 <option>main</option>,
326 <option>control</option> or
327 <option>all</option> to select whether
328 to kill only the main process of the
329 unit, the control process or all
330 processes of the unit. If omitted
332 <option>all</option>.</para></listitem>
336 <term><option>--signal=</option></term>
337 <term><option>-s</option></term>
339 <listitem><para>When used with
340 <command>kill</command>, choose which
341 signal to send to selected
342 processes. Must be one of the well
343 known signal specifiers such as
344 SIGTERM, SIGINT or SIGSTOP. If
346 <option>SIGTERM</option>.</para></listitem>
350 <term><option>--force</option></term>
351 <term><option>-f</option></term>
353 <listitem><para>When used with
354 <command>enable</command>, override any
356 symlinks.</para></listitem>
358 <listitem><para>When used with
359 <command>halt</command>,
360 <command>poweroff</command>,
361 <command>reboot</command> or
362 <command>kexec</command> execute
363 selected operation without shutting
364 down all units. However, all processes
365 will be killed forcibly and all file
366 systems are unmounted or remounted
367 read-only. This is hence a drastic but
368 relatively safe option to request an
369 immediate reboot.</para></listitem>
373 <term><option>--defaults</option></term>
375 <listitem><para>When used with
376 <command>disable</command>, ensures
377 that only the symlinks created by
378 <command>enable</command> are removed,
379 not all symlinks pointing to the unit
381 disabled.</para></listitem>
385 <term><option>--root=</option></term>
387 <listitem><para>When used with
388 <command>enable</command>/
389 <command>disable</command>/
390 <command>is-enabled</command>,
391 use alternative root path for systemd
392 install.</para></listitem>
396 <term><option>-H</option></term>
397 <term><option>--host</option></term>
399 <listitem><para>Execute operation
400 remotely. Specify a hostname, or
401 username and hostname separated by @,
402 to connect to. This will use SSH to
403 talk to the remote systemd
404 instance.</para></listitem>
408 <term><option>-P</option></term>
409 <term><option>--privileged</option></term>
411 <listitem><para>Acquire privileges via
412 PolicyKit before executing the
413 operation.</para></listitem>
417 <para>The following commands are understood:</para>
421 <term><command>list-units</command></term>
423 <listitem><para>List known units.</para></listitem>
426 <term><command>start [NAME...]</command></term>
428 <listitem><para>Start (activate) one
429 or more units specified on the command
430 line.</para></listitem>
433 <term><command>stop [NAME...]</command></term>
435 <listitem><para>Stop (deactivate) one
436 or more units specified on the command
437 line.</para></listitem>
440 <term><command>reload [NAME...]</command></term>
442 <listitem><para>Asks all units listed
443 on the command line to reload their
444 configuration. Note that this will
445 reload the service-specific
446 configuration, not the unit
447 configuration file of systemd. If you
448 want systemd to reload the
449 configuration file of a unit use the
450 <command>daemon-reload</command>
451 command. In other words: for the
452 example case of Apache, this will
454 <filename>httpd.conf</filename> in the
456 <filename>apache.service</filename>
457 systemd unit file. </para>
459 <para>This command should not be
461 <command>daemon-reload</command> or
462 <command>load</command>
463 commands.</para></listitem>
467 <term><command>restart [NAME...]</command></term>
469 <listitem><para>Restart one or more
470 units specified on the command
471 line. If the units are not running yet
473 started.</para></listitem>
476 <term><command>try-restart [NAME...]</command></term>
478 <listitem><para>Restart one or more
479 units specified on the command
480 line if the units are running. Do
481 nothing if units are not running.
482 Note that for compatibility
483 with Red Hat init scripts
484 <command>condrestart</command> is
485 equivalent to this command.</para></listitem>
488 <term><command>reload-or-restart [NAME...]</command></term>
490 <listitem><para>Reload one or more
491 units if they support it. If not,
492 restart them instead. If the units
493 are not running yet they will be
494 started.</para></listitem>
497 <term><command>reload-or-try-restart [NAME...]</command></term>
499 <listitem><para>Reload one or more
500 units if they support it. If not,
501 restart them instead. Do nothing if
502 the units are not running. Note that
503 for compatibility with SysV init
505 <command>force-reload</command> is
507 command.</para></listitem>
510 <term><command>isolate [NAME]</command></term>
512 <listitem><para>Start the unit
513 specified on the command line and its
514 dependencies and stop all others.</para>
516 <para>This is similar to changing the
517 runlevel in a traditional init system. The
518 <command>isolate</command> command will
519 immediately stop processes that are not
520 enabled in the new unit, possibly including
521 the graphical environment or terminal you
522 are currently using.</para>
524 <para>Note that this works only on units
525 where <option>AllowIsolate=</option> is
527 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
528 for details.</para></listitem>
531 <term><command>kill [NAME...]</command></term>
533 <listitem><para>Send a signal to one
534 or more processes of the unit. Use
535 <option>--kill-who=</option> to select
536 which process to kill. Use
537 <option>--kill-mode=</option> to
538 select the kill mode and
539 <option>--signal=</option> to select
540 the signal to send.</para></listitem>
543 <term><command>is-active [NAME...]</command></term>
545 <listitem><para>Check whether any of
546 the specified units are active
547 (i.e. running). Returns an exit code
548 0 if at least one is active, non-zero
550 <option>--quiet</option> is specified
551 this will also print the current unit
552 state to STDOUT.</para></listitem>
555 <term><command>status [NAME...|PID...]</command></term>
557 <listitem><para>Show terse runtime
558 status information about one or more
559 units. This function is intended to
560 generate human-readable output. If you
561 are looking for computer-parsable
562 output, use <command>show</command>
563 instead. If a PID is passed
564 information about the unit the process
565 of the PID belongs to is
566 shown.</para></listitem>
569 <term><command>show [NAME...|JOB...]</command></term>
571 <listitem><para>Show properties of one
572 or more units, jobs or the manager
573 itself. If no argument is specified
574 properties of the manager will be
575 shown. If a unit name is specified
576 properties of the unit is shown, and
577 if a job id is specified properties of
578 the job is shown. By default, empty
579 properties are suppressed. Use
580 <option>--all</option> to show those
581 too. To select specific properties to
583 <option>--property=</option>. This
584 command is intended to be used
585 whenever computer-parsable output is
587 <command>status</command> if you are
588 looking for formatted human-readable
589 output.</para></listitem>
593 <term><command>reset-failed [NAME...]</command></term>
595 <listitem><para>Reset the
596 '<literal>failed</literal>' state of the
597 specified units, or if no unit name is
598 passed of all units. When a unit fails
599 in some way (i.e. process exiting with
600 non-zero error code, terminating
601 abnormally or timing out) it will
602 automatically enter the
603 '<literal>failed</literal>' state and
604 its exit code and status is recorded
605 for introspection by the administrator
606 until the service is restarted or
608 command.</para></listitem>
612 <term><command>enable [NAME...]</command></term>
614 <listitem><para>Enable one or more
615 unit files, as specified on the
616 command line. This will create a
617 number of symlinks as encoded in the
618 <literal>[Install]</literal> sections
619 of the unit files. After the symlinks
620 have been created the systemd
621 configuration is reloaded (in a way
622 that is equivalent to
623 <command>daemon-reload</command>) to
624 ensure the changes are taken into
625 account immediately. Note that this
626 does not have the effect that any of
627 the units enabled are also started at
628 the same time. If this is desired a
629 separate <command>start</command>
630 command must be invoked for the
633 <para>This command will
634 print the actions executed. This
635 output may be suppressed by passing
636 <option>--quiet</option>.</para>
638 <para>Note that this operation creates
639 only the suggested symlinks for the
640 units. While this command is the
641 recommended way to manipulate the unit
642 configuration directory, the
643 administrator is free to make
644 additional changes manually, by
645 placing or removing symlinks in the
646 directory. This is particularly useful
647 to create configurations that deviate
648 from the suggested default
649 installation. In this case the
650 administrator must make sure to invoke
651 <command>daemon-reload</command>
652 manually as necessary, to ensure his
653 changes are taken into account.</para>
655 <para>Enabling units should not be
656 confused with starting (activating)
657 units, as done by the
658 <command>start</command>
659 command. Enabling and starting units
660 is orthogonal: units may be enabled
661 without being started and started
662 without being enabled. Enabling simply
663 hooks the unit into various suggested
664 places (for example, so that the unit
665 is automatically started on boot or
666 when a particular kind of hardware is
667 plugged in). Starting actually spawns
668 the daemon process (in case of service
669 units), or binds the socket (in case
670 of socket units), and so
673 <para>Depending on whether
674 <option>--system</option>,
675 <option>--user</option> or
676 <option>--global</option> is specified
677 this enables the unit for the system,
678 for the calling user only
679 or for all future logins of all
680 users. Note that in the latter case no
681 systemd daemon configuration is
687 <term><command>disable [NAME...]</command></term>
689 <listitem><para>Disables one or more
690 units. This removes all symlinks to
691 the specified unit files from the unit
692 configuration directory, and hence
693 undoes the changes made by
694 <command>enable</command>. Note
695 however that this by default removes
696 all symlinks to the unit files
697 (i.e. including manual additions), not
698 just those actually created by
699 <command>enable</command>. If only the
700 symlinks that are suggested by default
701 shall be removed, pass
702 <option>--defaults</option>. This
703 implicitly reloads the systemd daemon
704 configuration after completing the
705 disabling of the units. Note that this
706 command does not implicitly stop the
707 units that is being disabled. If this
708 is desired an additional
709 <command>stop</command>command should
710 be executed afterwards.</para>
712 <para>This command will print the
713 actions executed. This output may be
714 suppressed by passing
715 <option>--quiet</option>.</para>
718 <para>This command honors
719 <option>--system</option>,
720 <option>--user</option>,
721 <option>--global</option> in a similar
723 <command>enable</command>.</para>
727 <term><command>is-enabled [NAME...]</command></term>
729 <listitem><para>Checks whether any of
730 the specified unit files is enabled
732 <command>enable</command>). Returns an
733 exit code of 0 if at least one is
735 otherwise.</para></listitem>
739 <term><command>load [NAME...]</command></term>
741 <listitem><para>Load one or more units
742 specified on the command line. This
743 will simply load their configuration
744 from disk, but not start them. To
745 start them you need to use the
746 <command>start</command> command which
747 will implicitly load a unit that has
748 not been loaded yet. Note that systemd
749 garbage collects loaded units that are
750 not active or referenced by an active
751 unit. This means that units loaded
752 this way will usually not stay loaded
753 for long. Also note that this command
754 cannot be used to reload unit
755 configuration. Use the
756 <command>daemon-reload</command>
757 command for that. All in all, this
758 command is of little use except for
760 <para>This command should not be
762 <command>daemon-reload</command> or
763 <command>reload</command>
764 commands.</para></listitem>
767 <term><command>list-jobs</command></term>
769 <listitem><para>List jobs that are in progress.</para></listitem>
772 <term><command>cancel [JOB...]</command></term>
774 <listitem><para>Cancel one or more
775 jobs specified on the command line by
777 IDs. If no job id is specified, cancel all pending jobs.</para></listitem>
780 <term><command>monitor</command></term>
782 <listitem><para>Monitor unit/job
783 changes. This is mostly useful for
784 debugging purposes and prints a line
785 each time systemd loads or unloads a
786 unit configuration file, or a unit
787 property changes.</para></listitem>
790 <term><command>dump</command></term>
792 <listitem><para>Dump server
793 status. This will output a (usually
794 very long) human readable manager
795 status dump. Its format is subject to
796 change without notice and should not
798 applications.</para></listitem>
801 <term><command>dot</command></term>
803 <listitem><para>Generate textual
804 dependency graph description in dot
805 format for further processing with the
807 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
808 tool. Use a command line like
809 <command>systemctl dot | dot -Tsvg >
810 systemd.svg</command> to generate a
811 graphical dependency tree. Unless
812 <option>--order</option> or
813 <option>--require</option> is passed
814 the generated graph will show both
815 ordering and requirement
816 dependencies.</para></listitem>
819 <term><command>snapshot [NAME]</command></term>
821 <listitem><para>Create a snapshot. If
822 a snapshot name is specified, the new
823 snapshot will be named after it. If
824 none is specified an automatic
825 snapshot name is generated. In either
826 case, the snapshot name used is
827 printed to STDOUT, unless
828 <option>--quiet</option> is
831 <para>A snapshot refers to a saved
832 state of the systemd manager. It is
833 implemented itself as a unit that is
834 generated dynamically with this
835 command and has dependencies on all
836 units active at the time. At a later
837 time the user may return to this state
839 <command>isolate</command> command on
840 the snapshot unit.</para></listitem>
842 <para>Snapshots are only useful for
843 saving and restoring which units are
844 running or are stopped, they do not
845 save/restore any other
846 state. Snapshots are dynamic and lost
850 <term><command>delete [NAME...]</command></term>
852 <listitem><para>Remove a snapshot
853 previously created with
854 <command>snapshot</command>.</para></listitem>
857 <term><command>daemon-reload</command></term>
859 <listitem><para>Reload systemd manager
860 configuration. This will reload all
861 unit files and recreate the entire
862 dependency tree. While the daemon is
863 reloaded, all sockets systemd listens
864 on on behalf of user configuration will
865 stay accessible.</para> <para>This
866 command should not be confused with
867 the <command>load</command> or
868 <command>reload</command>
869 commands.</para></listitem>
872 <term><command>daemon-reexec</command></term>
874 <listitem><para>Reexecute the systemd
875 manager. This will serialize the
876 manager state, reexecute the process
877 and deserialize the state again. This
878 command is of little use except for
879 debugging and package
880 upgrades. Sometimes it might be
881 helpful as a heavy-weight
882 <command>daemon-reload</command>. While
883 the daemon is reexecuted all sockets
884 systemd listens on on behalf of user
885 configuration will stay
886 accessible.</para></listitem>
889 <term><command>show-environment</command></term>
891 <listitem><para>Dump the systemd
892 manager environment block. The
893 environment block will be dumped in
894 straight-forward form suitable for
895 sourcing into a shell script. This
896 environment block will be passed to
897 all processes the manager
898 spawns.</para></listitem>
901 <term><command>set-environment [NAME=VALUE...]</command></term>
903 <listitem><para>Set one or more
904 systemd manager environment variables,
905 as specified on the command
906 line.</para></listitem>
909 <term><command>unset-environment [NAME...]</command></term>
911 <listitem><para>Unset one or more
912 systemd manager environment
913 variables. If only a variable name is
914 specified it will be removed
915 regardless of its value. If a variable
916 and a value are specified the variable
917 is only removed if it has the
918 specified value.</para></listitem>
921 <term><command>default</command></term>
923 <listitem><para>Enter default
924 mode. This is mostly equivalent to
926 default.target</command>.</para></listitem>
929 <term><command>rescue</command></term>
931 <listitem><para>Enter rescue
932 mode. This is mostly equivalent to
934 rescue.target</command> but also
935 prints a wall message to all
936 users.</para></listitem>
939 <term><command>emergency</command></term>
941 <listitem><para>Enter emergency
942 mode. This is mostly equivalent to
944 emergency.target</command> but also
945 prints a wall message to all
946 users.</para></listitem>
949 <term><command>halt</command></term>
951 <listitem><para>Shut down and halt the
952 system. This is mostly equivalent to
953 <command>start halt.target</command>
954 but also prints a wall message to all
956 combined with <option>--force</option>
957 shutdown of all running services is
958 skipped, however all processes are killed
959 and all file systems are unmounted or
960 mounted read-only, immediately
962 system halt.</para></listitem>
965 <term><command>poweroff</command></term>
967 <listitem><para>Shut down and
968 power-off the system. This is mostly
969 equivalent to <command>start
970 poweroff.target</command> but also
971 prints a wall message to all
973 combined with <option>--force</option>
974 shutdown of all running services is
975 skipped, however all processes are killed
976 and all file systems are unmounted or
977 mounted read-only, immediately
979 powering off.</para></listitem>
982 <term><command>reboot</command></term>
984 <listitem><para>Shut down and
985 reboot the system. This is mostly
986 equivalent to <command>start
987 reboot.target</command> but also
988 prints a wall message to all
990 combined with <option>--force</option>
991 shutdown of all running services is
992 skipped, however all processes are killed
993 and all file systems are unmounted or
994 mounted read-only, immediately
996 reboot.</para></listitem>
999 <term><command>kexec</command></term>
1001 <listitem><para>Shut down and reboot
1002 the system via kexec. This is mostly
1003 equivalent to <command>start
1004 kexec.target</command> but also prints
1005 a wall message to all users. If
1006 combined with <option>--force</option>
1007 shutdown of all running services is
1008 skipped, however all processes are killed
1009 and all file systems are unmounted or
1010 mounted read-only, immediately
1012 reboot.</para></listitem>
1015 <term><command>exit</command></term>
1017 <listitem><para>Ask the systemd
1018 manager to quit. This is only
1019 supported for user service managers
1020 (i.e. in conjunction with the
1021 <option>--user</option> option) and
1022 will fail otherwise.</para></listitem>
1029 <title>Exit status</title>
1031 <para>On success 0 is returned, a non-zero failure
1032 code otherwise.</para>
1036 <title>Environment</title>
1040 <term><varname>$SYSTEMD_PAGER</varname></term>
1041 <listitem><para>Pager to use when
1042 <option>--no-pager</option> is not given;
1043 overrides <varname>$PAGER</varname>. Setting
1044 this to an empty string or the value
1045 <literal>cat</literal> is equivalent to passing
1046 <option>--no-pager</option>.</para></listitem>
1052 <title>See Also</title>
1054 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1055 <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1056 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1057 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1058 <citerefentry><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>