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7 This file is part of systemd.
9 Copyright 2010 Lennart Poettering
11 systemd is free software; you can redistribute it and/or modify it
12 under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
16 systemd is distributed in the hope that it will be useful, but
17 WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 General Public License for more details.
21 You should have received a copy of the GNU General Public License
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25 <refentry id="systemd.exec">
27 <title>systemd.exec</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.exec</refentrytitle>
42 <manvolnum>5</manvolnum>
46 <refname>systemd.exec</refname>
47 <refpurpose>systemd execution environment configuration</refpurpose>
51 <para><filename>systemd.service</filename>,
52 <filename>systemd.socket</filename>,
53 <filename>systemd.mount</filename>,
54 <filename>systemd.swap</filename></para>
58 <title>Description</title>
60 <para>Unit configuration files for services, sockets
61 mount points and swap devices share a subset of
62 configuration options which define the execution
63 environment of spawned processes.</para>
65 <para>This man page lists the configuration options
66 shared by these three unit types. See
67 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
68 for the common options of all unit configuration
70 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
71 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
72 <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>
74 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
75 for more information on the specific unit
76 configuration files. The execution specific
77 configuration options are configured in the [Service],
78 [Socket], [Mount] resp. [Swap] section, depending on the unit
83 <title>Options</title>
88 <term><varname>WorkingDirectory=</varname></term>
90 <listitem><para>Takes an absolute
91 directory path. Sets the working
92 directory for executed
93 processes.</para></listitem>
97 <term><varname>RootDirectory=</varname></term>
99 <listitem><para>Takes an absolute
100 directory path. Sets the root
101 directory for executed processes, with
103 <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
104 system call. If this is used it must
105 be ensured that the process and all
106 its auxiliary files are available in
107 the <function>chroot()</function>
108 jail.</para></listitem>
112 <term><varname>User=</varname></term>
113 <term><varname>Group=</varname></term>
115 <listitem><para>Sets the Unix user
116 resp. group the processes are executed
117 as. Takes a single user resp. group
118 name or ID as argument. If no group is
119 set the default group of the user is
120 chosen.</para></listitem>
124 <term><varname>SupplementaryGroups=</varname></term>
126 <listitem><para>Sets the supplementary
127 Unix groups the processes are executed
128 as. This takes a space separated list
129 of group names or IDs. This option may
130 be specified more than once in which
131 case all listed groups are set as
132 supplementary groups. This option does
133 not override but extends the list of
134 supplementary groups configured in the
135 system group database for the
136 user.</para></listitem>
140 <term><varname>Nice=</varname></term>
142 <listitem><para>Sets the default nice
143 level (scheduling priority) for
144 executed processes. Takes an integer
145 between -20 (highest priority) and 19
146 (lowest priority). See
147 <citerefentry><refentrytitle>setpriority</refentrytitle><manvolnum>2</manvolnum></citerefentry>
148 for details.</para></listitem>
152 <term><varname>OOMScoreAdjust=</varname></term>
154 <listitem><para>Sets the adjustment
155 level for the Out-Of-Memory killer for
156 executed processes. Takes an integer
157 between -1000 (to disable OOM killing
158 for this process) and 1000 (to make
159 killing of this process under memory
160 pressure very likely). See <ulink
161 url="http://www.kernel.org/doc/Documentation/filesystems/proc.txt">proc.txt</ulink>
162 for details.</para></listitem>
166 <term><varname>IOSchedulingClass=</varname></term>
168 <listitem><para>Sets the IO scheduling
169 class for executed processes. Takes an
170 integer between 0 and 3 or one of the
171 strings <option>none</option>,
172 <option>realtime</option>,
173 <option>best-effort</option> or
174 <option>idle</option>. See
175 <citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
176 for details.</para></listitem>
180 <term><varname>IOSchedulingPriority=</varname></term>
182 <listitem><para>Sets the IO scheduling
183 priority for executed processes. Takes
184 an integer between 0 (highest
185 priority) and 7 (lowest priority). The
186 available priorities depend on the
187 selected IO scheduling class (see
189 <citerefentry><refentrytitle>ioprio_set</refentrytitle><manvolnum>2</manvolnum></citerefentry>
190 for details.</para></listitem>
194 <term><varname>CPUSchedulingPolicy=</varname></term>
196 <listitem><para>Sets the CPU
197 scheduling policy for executed
198 processes. Takes one of
199 <option>other</option>,
200 <option>batch</option>,
201 <option>idle</option>,
202 <option>fifo</option> or
203 <option>rr</option>. See
204 <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
205 for details.</para></listitem>
209 <term><varname>CPUSchedulingPriority=</varname></term>
211 <listitem><para>Sets the CPU
212 scheduling priority for executed
213 processes. Takes an integer between 1
214 (lowest priority) and 99 (highest
215 priority). The available priority
216 range depends on the selected CPU
217 scheduling policy (see above). See
218 <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
219 for details.</para></listitem>
223 <term><varname>CPUSchedulingResetOnFork=</varname></term>
225 <listitem><para>Takes a boolean
226 argument. If true elevated CPU
227 scheduling priorities and policies
228 will be reset when the executed
229 processes fork, and can hence not leak
230 into child processes. See
231 <citerefentry><refentrytitle>sched_setscheduler</refentrytitle><manvolnum>2</manvolnum></citerefentry>
232 for details. Defaults to false.</para></listitem>
236 <term><varname>CPUAffinity=</varname></term>
238 <listitem><para>Controls the CPU
239 affinity of the executed
240 processes. Takes a space-separated
241 list of CPU indexes. See
242 <citerefentry><refentrytitle>sched_setaffinity</refentrytitle><manvolnum>2</manvolnum></citerefentry>
243 for details.</para></listitem>
247 <term><varname>UMask=</varname></term>
249 <listitem><para>Controls the file mode
250 creation mask. Takes an access mode in
252 <citerefentry><refentrytitle>umask</refentrytitle><manvolnum>2</manvolnum></citerefentry>
253 for details. Defaults to
254 0002.</para></listitem>
258 <term><varname>Environment=</varname></term>
260 <listitem><para>Sets environment
261 variables for executed
262 processes. Takes a space-separated
263 list of variable assignments. This
264 option may be specified more than once
265 in which case all listed variables
266 will be set. If the same variable is
267 set twice the later setting will
268 override the earlier setting. See
269 <citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
270 for details.</para></listitem>
273 <term><varname>EnvironmentFile=</varname></term>
274 <listitem><para>Similar to
275 <varname>Environment=</varname> but
276 reads the environment variables from a
277 text file. The text file should
278 contain new-line separated variable
279 assignments. Empty lines and lines
280 starting with ; or # will be ignored,
281 which may be used for commenting. The
282 argument passed should be an absolute
283 file name, optionally prefixed with
284 "-", which indicates that if the file
285 does not exist it won't be read and no
286 error or warning message is
287 logged. The files listed with this
288 directive will be read shortly before
289 the process is executed. Settings from
290 these files override settings made
292 <varname>Environment=</varname>. If
293 the same variable is set twice from
294 these files the files will be read in
295 the order they are specified and the
296 later setting will override the
297 earlier setting. </para></listitem>
301 <term><varname>StandardInput=</varname></term>
302 <listitem><para>Controls where file
303 descriptor 0 (STDIN) of the executed
304 processes is connected to. Takes one
305 of <option>null</option>,
306 <option>tty</option>,
307 <option>tty-force</option>,
308 <option>tty-fail</option> or
309 <option>socket</option>. If
310 <option>null</option> is selected
311 standard input will be connected to
312 <filename>/dev/null</filename>,
313 i.e. all read attempts by the process
314 will result in immediate EOF. If
315 <option>tty</option> is selected
316 standard input is connected to a TTY
318 <varname>TTYPath=</varname>, see
319 below) and the executed process
320 becomes the controlling process of the
321 terminal. If the terminal is already
322 being controlled by another process the
323 executed process waits until the current
324 controlling process releases the
326 <option>tty-force</option>
327 is similar to <option>tty</option>,
328 but the executed process is forcefully
329 and immediately made the controlling
330 process of the terminal, potentially
331 removing previous controlling
333 terminal. <option>tty-fail</option> is
334 similar to <option>tty</option> but if
335 the terminal already has a controlling
336 process start-up of the executed
338 <option>socket</option> option is only
339 valid in socket-activated services,
340 and only when the socket configuration
342 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
343 for details) specifies a single socket
344 only. If this option is set standard
345 input will be connected to the socket
346 the service was activated from, which
347 is primarily useful for compatibility
348 with daemons designed for use with the
350 <citerefentry><refentrytitle>inetd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
351 daemon. This setting defaults to
352 <option>null</option>.</para></listitem>
355 <term><varname>StandardOutput=</varname></term>
356 <listitem><para>Controls where file
357 descriptor 1 (STDOUT) of the executed
358 processes is connected to. Takes one
359 of <option>inherit</option>,
360 <option>null</option>,
361 <option>tty</option>,
362 <option>syslog</option>,
363 <option>kmsg</option>,
364 <option>kmsg+console</option>,
365 <option>syslog+console</option> or
366 <option>socket</option>. If set to
367 <option>inherit</option> the file
368 descriptor of standard input is
369 duplicated for standard output. If set
370 to <option>null</option> standard
371 output will be connected to
372 <filename>/dev/null</filename>,
373 i.e. everything written to it will be
374 lost. If set to <option>tty</option>
375 standard output will be connected to a
376 tty (as configured via
377 <varname>TTYPath=</varname>, see
378 below). If the TTY is used for output
379 only the executed process will not
380 become the controlling process of the
381 terminal, and will not fail or wait
382 for other processes to release the
383 terminal. <option>syslog</option>
384 connects standard output to the
385 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
386 system logger. <option>kmsg</option>
387 connects it with the kernel log buffer
388 which is accessible via
389 <citerefentry><refentrytitle>dmesg</refentrytitle><manvolnum>1</manvolnum></citerefentry>. <option>syslog+console</option>
390 and <option>kmsg+console</option> work
391 similarly but copy the output to the
393 well. <option>socket</option> connects
394 standard output to a socket from
395 socket activation, semantics are
396 similar to the respective option of
397 <varname>StandardInput=</varname>.
398 This setting defaults to
399 <option>inherit</option>.</para></listitem>
402 <term><varname>StandardError=</varname></term>
403 <listitem><para>Controls where file
404 descriptor 2 (STDERR) of the executed
405 processes is connected to. The
406 available options are identical to
408 <varname>StandardOutput=</varname>,
409 with one exception: if set to
410 <option>inherit</option> the file
411 descriptor used for standard output is
412 duplicated for standard error. This
414 <option>inherit</option>.</para></listitem>
417 <term><varname>TTYPath=</varname></term>
418 <listitem><para>Sets the terminal
419 device node to use if standard input,
420 output or stderr are connected to a
421 TTY (see above). Defaults to
422 <filename>/dev/console</filename>.</para></listitem>
425 <term><varname>SyslogIdentifier=</varname></term>
426 <listitem><para>Sets the process name
427 to prefix log lines sent to syslog or
428 the kernel log buffer with. If not set
429 defaults to the process name of the
430 executed process. This option is only
432 <varname>StandardOutput=</varname> or
433 <varname>StandardError=</varname> are
434 set to <option>syslog</option> or
435 <option>kmsg</option>.</para></listitem>
438 <term><varname>SyslogFacility=</varname></term>
439 <listitem><para>Sets the syslog
440 facility to use when logging to
441 syslog. One of <option>kern</option>,
442 <option>user</option>,
443 <option>mail</option>,
444 <option>daemon</option>,
445 <option>auth</option>,
446 <option>syslog</option>,
447 <option>lpr</option>,
448 <option>news</option>,
449 <option>uucp</option>,
450 <option>cron</option>,
451 <option>authpriv</option>,
452 <option>ftp</option>,
453 <option>local0</option>,
454 <option>local1</option>,
455 <option>local2</option>,
456 <option>local3</option>,
457 <option>local4</option>,
458 <option>local5</option>,
459 <option>local6</option> or
460 <option>local7</option>. See
461 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
462 for details. This option is only
464 <varname>StandardOutput=</varname> or
465 <varname>StandardError=</varname> are
466 set to <option>syslog</option>.
468 <option>daemon</option>.</para></listitem>
471 <term><varname>SyslogLevel=</varname></term>
472 <listitem><para>Default syslog level
473 to use when logging to syslog or the
474 kernel log buffer. One of
475 <option>emerg</option>,
476 <option>alert</option>,
477 <option>crit</option>,
478 <option>err</option>,
479 <option>warning</option>,
480 <option>notice</option>,
481 <option>info</option>,
482 <option>debug</option>. See
483 <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
484 for details. This option is only
486 <varname>StandardOutput=</varname> or
487 <varname>StandardError=</varname> are
488 set to <option>syslog</option> or
489 <option>kmsg</option>. Note that
490 individual lines output by the daemon
491 might be prefixed with a different log
492 level which can be used to override
493 the default log level specified
494 here. The interpretation of these
495 prefixes may be disabled with
496 <varname>SyslogLevelPrefix=</varname>,
497 see below. For details see
498 <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
501 <option>info</option>.</para></listitem>
505 <term><varname>SyslogLevelPrefix=</varname></term>
506 <listitem><para>Takes a boolean
507 argument. If true and
508 <varname>StandardOutput=</varname> or
509 <varname>StandardError=</varname> are
510 set to <option>syslog</option> or
511 <option>kmsg</option> log lines
512 written by the executed process that
513 are prefixed with a log level will be
514 passed on to syslog with this log
515 level set but the prefix removed. If
516 set to false, the interpretation of
517 these prefixes is disabled and the
518 logged lines are passed on as-is. For
519 details about this prefixing see
520 <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
521 Defaults to true.</para></listitem>
525 <term><varname>TimerSlackNSec=</varname></term>
526 <listitem><para>Sets the timer slack
527 in nanoseconds for the executed
528 processes. The timer slack controls the
529 accuracy of wake-ups triggered by
531 <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
532 for more information. Note that in
533 contrast to most other time span
534 definitions this parameter takes an
535 integer value in nano-seconds and does
536 not understand any other
537 units.</para></listitem>
541 <term><varname>LimitCPU=</varname></term>
542 <term><varname>LimitFSIZE=</varname></term>
543 <term><varname>LimitDATA=</varname></term>
544 <term><varname>LimitSTACK=</varname></term>
545 <term><varname>LimitCORE=</varname></term>
546 <term><varname>LimitRSS=</varname></term>
547 <term><varname>LimitNOFILE=</varname></term>
548 <term><varname>LimitAS=</varname></term>
549 <term><varname>LimitNPROC=</varname></term>
550 <term><varname>LimitMEMLOCK=</varname></term>
551 <term><varname>LimitLOCKS=</varname></term>
552 <term><varname>LimitSIGPENDING=</varname></term>
553 <term><varname>LimitMSGQUEUE=</varname></term>
554 <term><varname>LimitNICE=</varname></term>
555 <term><varname>LimitRTPRIO=</varname></term>
556 <term><varname>LimitRTTIME=</varname></term>
557 <listitem><para>These settings control
558 various resource limits for executed
560 <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
561 for details.</para></listitem>
565 <term><varname>PAMName=</varname></term>
566 <listitem><para>Sets the PAM service
567 name to set up a session as. If set
568 the executed process will be
569 registered as a PAM session under the
570 specified service name. This is only
571 useful in conjunction with the
572 <varname>User=</varname> setting. If
573 not set no PAM session will be opened
574 for the executed processes. See
575 <citerefentry><refentrytitle>pam</refentrytitle><manvolnum>8</manvolnum></citerefentry>
576 for details.</para></listitem>
580 <term><varname>TCPWrapName=</varname></term>
581 <listitem><para>If this is a
582 socket-activated service this sets the
583 tcpwrap service name to check the
584 permission for the current connection
585 with. This is only useful in
586 conjunction with socket-activated
587 services, and stream sockets (TCP) in
588 particular. It has no effect on other
589 socket types (e.g. datagram/UDP) and on processes
590 unrelated to socket-based
591 activation. If the tcpwrap
592 verification fails daemon start-up
593 will fail and the connection is
595 <citerefentry><refentrytitle>tcpd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
596 for details.</para></listitem>
600 <term><varname>CapabilityBoundingSet=</varname></term>
602 <listitem><para>Controls which
603 capabilities to include in the
604 capability bounding set for the
605 executed process. See
606 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
607 for details. Takes a whitespace
608 seperated list of capability names as
610 <citerefentry><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
611 Capabilities listed will be included
612 in the bounding set, all others are
613 removed. If the list of capabilities
614 is prefixed with ~ all but the listed
615 capabilities will be included, the
616 effect of this assignment
617 inverted. Note that this option does
618 not actually set or unset any
619 capabilities in the effective,
620 permitted or inherited capability
622 <varname>Capabilities=</varname> is
623 for. If this option is not used the
624 capability bounding set is not
625 modified on process execution, hence
626 no limits on the capabilities of the
627 process are enforced.</para></listitem>
631 <term><varname>SecureBits=</varname></term>
632 <listitem><para>Controls the secure
633 bits set for the executed process. See
634 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
635 for details. Takes a list of strings:
636 <option>keep-caps</option>,
637 <option>keep-caps-locked</option>,
638 <option>no-setuid-fixup</option>,
639 <option>no-setuid-fixup-locked</option>,
640 <option>no-setuid-noroot</option> and/or
641 <option>no-setuid-noroot-locked</option>.
646 <term><varname>Capabilities=</varname></term>
647 <listitem><para>Controls the
648 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
649 set for the executed process. Take a
650 capability string describing the
651 effective, permitted and inherited
652 capability sets as documented in
653 <citerefentry><refentrytitle>cap_from_text</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
654 Note that these capability sets are
655 usually influenced by the capabilities
656 attached to the executed file. Due to
658 <varname>CapabilityBoundingSet=</varname>
659 is probably the much more useful
660 setting.</para></listitem>
664 <term><varname>ControlGroup=</varname></term>
666 <listitem><para>Controls the control
667 groups the executed processes shall be
668 made members of. Takes a
669 space-separated list of cgroup
670 identifiers. A cgroup identifier has a
672 <filename>cpu:/foo/bar</filename>,
673 where "cpu" identifies the kernel
674 control group controller used, and
675 <filename>/foo/bar</filename> is the
676 control group path. The controller name
677 and ":" may be omitted in which case
678 the named systemd control group
679 hierarchy is implied. Alternatively,
680 the path and ":" may be omitted, in
681 which case the default control group
682 path for this unit is implied. This
683 option may be used to place executed
684 processes in arbitrary groups in
685 arbitrary hierachies -- which can be
686 configured externally with additional execution limits. By default
687 systemd will place all executed
688 processes in separate per-unit control
689 groups (named after the unit) in the
690 systemd named hierarchy. Since every
691 process can be in one group per
692 hierarchy only overriding the control group
693 path in the named systemd hierarchy
694 will disable automatic placement in
695 the default group. For details about control
697 url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>.</para></listitem>
701 <term><varname>ReadWriteDirectories=</varname></term>
702 <term><varname>ReadOnlyDirectories=</varname></term>
703 <term><varname>InaccessibleDirectories=</varname></term>
705 <listitem><para>Sets up a new
706 file-system name space for executed
707 processes. These options may be used
708 to limit access a process might have
709 to the main file-system
710 hierarchy. Each setting takes a
711 space-separated list of absolute
712 directory paths. Directories listed in
713 <varname>ReadWriteDirectories=</varname>
714 are accessible from within the
715 namespace with the same access rights
716 as from outside. Directories listed in
717 <varname>ReadOnlyDirectories=</varname>
718 are accessible for reading only,
719 writing will be refused even if the
720 usual file access controls would
721 permit this. Directories listed in
722 <varname>InaccessibleDirectories=</varname>
723 will be made inaccesible for processes
724 inside the namespace. Note that
725 restricting access with these options
726 does not extend to submounts of a
727 directory. You must list submounts
728 separately in these settings to
729 ensure the same limited access. These
730 options may be specified more than
731 once in which case all directories
732 listed will have limited access from
734 namespace.</para></listitem>
738 <term><varname>PrivateTmp=</varname></term>
740 <listitem><para>Takes a boolean
741 argument. If true sets up a new
742 namespace for the executed processes
744 <filename>/tmp</filename> directory
745 inside it, that is not shared by
746 processes outside of the
747 namespace. This is useful to secure
748 access to temporary files of the
749 process, but makes sharing between
751 <filename>/tmp</filename>
752 impossible. Defaults to false.</para></listitem>
756 <term><varname>MountFlags=</varname></term>
758 <listitem><para>Takes a mount
760 <option>shared</option>,
761 <option>slave</option> or
762 <option>private</option>, which
763 control whether namespaces set up with
764 <varname>ReadWriteDirectories=</varname>,
765 <varname>ReadOnlyDirectories=</varname>
767 <varname>InaccessibleDirectories=</varname>
768 receive or propagate new mounts
769 from/to the main namespace. See
770 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>1</manvolnum></citerefentry>
771 for details. Defaults to
772 <option>shared</option>, i.e. the new
773 namespace will both receive new mount
774 points from the main namespace as well
775 as propagate new mounts to
776 it.</para></listitem>
780 <term><varname>UtmpIdentifier=</varname></term>
782 <listitem><para>Takes a a four
783 character identifier string for an
784 utmp/wtmp entry for this service. This
785 should only be set for services such
786 as <command>getty</command>
787 implementations where utmp/wtmp
788 entries must be created and cleared
789 before and after execution. If the
790 configured string is longer than four
791 characters it is truncated and the
792 terminal four characters are
793 used. This setting interprets %I style
794 string replacements. This setting is
795 unset by default, i.e. no utmp/wtmp
796 entries are created or cleaned up for
797 this service.</para></listitem>
804 <title>See Also</title>
806 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
807 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
808 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
809 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
810 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
811 <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
812 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>