chiark / gitweb /
udevadm-settle: add missing brace
[elogind.git] / man / systemd.xml
1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
4
5 <!--
6   This file is part of systemd.
7
8   Copyright 2010 Lennart Poettering
9
10   systemd is free software; you can redistribute it and/or modify it
11   under the terms of the GNU Lesser General Public License as published by
12   the Free Software Foundation; either version 2.1 of the License, or
13   (at your option) any later version.
14
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   Lesser General Public License for more details.
19
20   You should have received a copy of the GNU Lesser General Public License
21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 -->
23
24 <refentry id="systemd">
25
26         <refentryinfo>
27                 <title>systemd</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Lennart</firstname>
34                                 <surname>Poettering</surname>
35                                 <email>lennart@poettering.net</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd</refentrytitle>
42                 <manvolnum>1</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd</refname>
47                 <refname>init</refname>
48                 <refpurpose>systemd system and service manager</refpurpose>
49         </refnamediv>
50
51         <refsynopsisdiv>
52                 <cmdsynopsis>
53                         <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command>
54                 </cmdsynopsis>
55                 <cmdsynopsis>
56                         <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
57                 </cmdsynopsis>
58         </refsynopsisdiv>
59
60         <refsect1>
61                 <title>Description</title>
62
63                 <para>systemd is a system and service 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>
67
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>
76
77                 <para>When run as system instance, systemd interprets
78                 the configuration file
79                 <filename>system.conf</filename>, otherwise
80                 <filename>user.conf</filename>. See
81                 <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
82                 for more information.</para>
83         </refsect1>
84
85         <refsect1>
86                 <title>Options</title>
87
88                 <para>The following options are understood:</para>
89
90                 <variablelist>
91                         <varlistentry>
92                                 <term><option>-h</option></term>
93                                 <term><option>--help</option></term>
94
95                                 <listitem><para>Prints a short help
96                                 text and exits.</para></listitem>
97                         </varlistentry>
98                         <varlistentry>
99                                 <term><option>--version</option></term>
100
101                                 <listitem><para>Prints a systemd version
102                                 identifier and exits.</para></listitem>
103                         </varlistentry>
104                         <varlistentry>
105                                 <term><option>--test</option></term>
106
107                                 <listitem><para>Determine startup
108                                 sequence, dump it and exit. This is an
109                                 option useful for debugging
110                                 only.</para></listitem>
111                         </varlistentry>
112                         <varlistentry>
113                                 <term><option>--dump-configuration-items</option></term>
114
115                                 <listitem><para>Dump understood unit
116                                 configuration items. This outputs a
117                                 terse but complete list of
118                                 configuration items understood in unit
119                                 definition files.</para></listitem>
120                         </varlistentry>
121                         <varlistentry>
122                                 <term><option>--unit=</option></term>
123
124                                 <listitem><para>Set default unit to
125                                 activate on startup. If not specified,
126                                 defaults to
127                                 <filename>default.target</filename>.</para></listitem>
128                         </varlistentry>
129                         <varlistentry>
130                                 <term><option>--system</option></term>
131                                 <term><option>--user</option></term>
132
133                                 <listitem><para>For <option>--system</option>,
134                                 tell systemd to run a
135                                 system instance, even if the process ID is
136                                 not 1, i.e. systemd is not run as init process.
137                                 <option>--user</option> does the opposite,
138                                 running a user instance even if the process
139                                 ID is 1.
140                                 Normally it should not be necessary to
141                                 pass these options, as systemd
142                                 automatically detects the mode it is
143                                 started in. These options are hence of
144                                 little use except for debugging. Note
145                                 that it is not supported booting and
146                                 maintaining a full system with systemd
147                                 running in <option>--system</option>
148                                 mode, but PID not 1. In practice,
149                                 passing <option>--system</option> explicitly is
150                                 only useful in conjunction with
151                                 <option>--test</option>.</para></listitem>
152                         </varlistentry>
153                         <varlistentry>
154                                 <term><option>--dump-core</option></term>
155
156                                 <listitem><para>Dump core on
157                                 crash. This switch has no effect when
158                                 run as user
159                                 instance.</para></listitem>
160                         </varlistentry>
161                         <varlistentry>
162                                 <term><option>--crash-shell</option></term>
163
164                                 <listitem><para>Run shell on
165                                 crash. This switch has no effect when
166                                 run as user
167                                 instance.</para></listitem>
168                         </varlistentry>
169                         <varlistentry>
170                                 <term><option>--confirm-spawn</option></term>
171
172                                 <listitem><para>Ask for confirmation
173                                 when spawning processes. This switch
174                                 has no effect when run as user
175                                 instance.</para></listitem>
176                         </varlistentry>
177                         <varlistentry>
178                                 <term><option>--show-status=</option></term>
179
180                                 <listitem><para>Show terse service
181                                 status information while booting. This
182                                 switch has no effect when run as user
183                                 instance. Takes a boolean argument
184                                 which may be omitted which is
185                                 interpreted as
186                                 <option>true</option>.</para></listitem>
187                         </varlistentry>
188                         <varlistentry>
189                                 <term><option>--log-target=</option></term>
190
191                                 <listitem><para>Set log
192                                 target. Argument must be one of
193                                 <option>console</option>,
194                                 <option>journal</option>,
195                                 <option>syslog</option>,
196                                 <option>kmsg</option>,
197                                 <option>journal-or-kmsg</option>,
198                                 <option>syslog-or-kmsg</option>,
199                                 <option>null</option>.</para></listitem>
200                         </varlistentry>
201                         <varlistentry>
202                                 <term><option>--log-level=</option></term>
203
204                                 <listitem><para>Set log level. As
205                                 argument this accepts a numerical log
206                                 level or the well-known <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>
207                                 symbolic names (lowercase):
208                                 <option>emerg</option>,
209                                 <option>alert</option>,
210                                 <option>crit</option>,
211                                 <option>err</option>,
212                                 <option>warning</option>,
213                                 <option>notice</option>,
214                                 <option>info</option>,
215                                 <option>debug</option>.</para></listitem>
216                         </varlistentry>
217                         <varlistentry>
218                                 <term><option>--log-color=</option></term>
219
220                                 <listitem><para>Highlight important
221                                 log messages. Argument is a boolean
222                                 value. If the argument is omitted, it
223                                 defaults to
224                                 <option>true</option>.</para></listitem>
225                         </varlistentry>
226                         <varlistentry>
227                                 <term><option>--log-location=</option></term>
228
229                                 <listitem><para>Include code location
230                                 in log messages. This is mostly
231                                 relevant for debugging
232                                 purposes. Argument is a boolean
233                                 value. If the argument is omitted
234                                 it defaults to
235                                 <option>true</option>.</para></listitem>
236                         </varlistentry>
237                         <varlistentry>
238                                 <term><option>--default-standard-output=</option></term>
239                                 <term><option>--default-standard-error=</option></term>
240
241                                 <listitem><para>Sets the default
242                                 output or error output for all
243                                 services and sockets, respectively. That is, controls
244                                 the default for
245                                 <option>StandardOutput=</option>
246                                 and <option>StandardError=</option>
247                                 (see
248                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
249                                 for details). Takes one of
250                                 <option>inherit</option>,
251                                 <option>null</option>,
252                                 <option>tty</option>,
253                                 <option>journal</option>,
254                                 <option>journal+console</option>,
255                                 <option>syslog</option>,
256                                 <option>syslog+console</option>,
257                                 <option>kmsg</option>,
258                                 <option>kmsg+console</option>.  If the
259                                 argument is omitted
260                                 <option>--default-standard-output=</option>
261                                 defaults to <option>journal</option>
262                                 and
263                                 <option>--default-standard-error=</option>
264                                 to
265                                 <option>inherit</option>.</para></listitem>
266                         </varlistentry>
267                 </variablelist>
268         </refsect1>
269
270         <refsect1>
271                 <title>Concepts</title>
272
273                 <para>systemd provides a dependency system between
274                 various entities called "units" of 12 different
275                 types. Units encapsulate various objects that are
276                 relevant for system boot-up and maintenance. The
277                 majority of units are configured in unit configuration
278                 files, whose syntax and basic set of options is
279                 described in
280                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
281                 however some are created automatically from other
282                 configuration, dynamically from system state or
283                 programmatically at runtime. Units may be "active"
284                 (meaning started, bound, plugged in, ..., depending on
285                 the unit type, see below), or "inactive" (meaning
286                 stopped, unbound, unplugged, ...), as well as in the
287                 process of being activated or deactivated,
288                 i.e. between the two states (these states are called
289                 "activating", "deactivating"). A special "failed"
290                 state is available as well, which is very similar to
291                 "inactive" and is entered when the service failed in
292                 some way (process returned error code on exit, or
293                 crashed, or an operation timed out). If this state is
294                 entered, the cause will be logged, for later
295                 reference. Note that the various unit types may have a
296                 number of additional substates, which are mapped to
297                 the five generalized unit states described
298                 here.</para>
299
300                 <para>The following unit types are available:</para>
301
302                 <orderedlist>
303                         <listitem><para>Service units, which start and control
304                         daemons and the processes they consist of. For
305                         details see
306                         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
307
308                         <listitem><para>Socket units, which
309                         encapsulate local IPC or network sockets in
310                         the system, useful for socket-based
311                         activation. For details about socket units see
312                         <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
313                         for details on socket-based activation and
314                         other forms of activation, see
315                         <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem>
316
317                         <listitem><para>Target units are useful to
318                         group units, or provide well-known
319                         synchronization points during boot-up, see
320                         <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
321
322                         <listitem><para>Device units expose kernel
323                         devices in systemd and may be used to
324                         implement device-based activation. For details
325                         see
326                         <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
327
328                         <listitem><para>Mount units control mount
329                         points in the file system, for details see
330                         <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
331
332                         <listitem><para>Automount units provide
333                         automount capabilities, for on-demand mounting
334                         of file systems as well as parallelized
335                         boot-up. See
336                         <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
337
338                         <listitem><para>Snapshot units can be used to
339                         temporarily save the state of the set of
340                         systemd units, which later may be restored by
341                         activating the saved snapshot unit. For more
342                         information see
343                         <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
344
345                         <listitem><para>Timer units are useful for
346                         triggering activation of other units based on
347                         timers. You may find details in
348                         <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
349
350                         <listitem><para>Swap units are very similar to
351                         mount units and encapsulate memory swap
352                         partitions or files of the operating
353                         system. They are described in <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
354
355                         <listitem><para>Path units may be used
356                         to activate other services when file system
357                         objects change or are modified. See
358                         <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
359
360                         <listitem><para>Slice units may be used to
361                         group units which manage system processes
362                         (such as service and scope units) in a
363                         hierarchical tree for resource management
364                         purposes. See
365                         <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
366
367                         <listitem><para>Scope units are similar to
368                         service units, but manage foreign processes
369                         instead of starting them as well. See
370                         <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
371
372                 </orderedlist>
373
374                 <para>Units are named as their configuration
375                 files. Some units have special semantics. A detailed
376                 list is available in
377                 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
378
379                 <para>systemd knows various kinds of dependencies,
380                 including positive and negative requirement
381                 dependencies (i.e. <varname>Requires=</varname> and
382                 <varname>Conflicts=</varname>) as well as ordering
383                 dependencies (<varname>After=</varname> and
384                 <varname>Before=</varname>). NB: ordering and
385                 requirement dependencies are orthogonal. If only a
386                 requirement dependency exists between two units
387                 (e.g. <filename>foo.service</filename> requires
388                 <filename>bar.service</filename>), but no ordering
389                 dependency (e.g. <filename>foo.service</filename>
390                 after <filename>bar.service</filename>) and both are
391                 requested to start, they will be started in
392                 parallel. It is a common pattern that both requirement
393                 and ordering dependencies are placed between two
394                 units. Also note that the majority of dependencies are
395                 implicitly created and maintained by systemd. In most
396                 cases it should be unnecessary to declare additional
397                 dependencies manually, however it is possible to do
398                 this.</para>
399
400                 <para>Application programs and units (via
401                 dependencies) may request state changes of units. In
402                 systemd, these requests are encapsulated as 'jobs' and
403                 maintained in a job queue. Jobs may succeed or can
404                 fail, their execution is ordered based on the ordering
405                 dependencies of the units they have been scheduled
406                 for.</para>
407
408                 <para>On boot systemd activates the target unit
409                 <filename>default.target</filename> whose job is to
410                 activate on-boot services and other on-boot units by
411                 pulling them in via dependencies. Usually the unit
412                 name is just an alias (symlink) for either
413                 <filename>graphical.target</filename> (for
414                 fully-featured boots into the UI) or
415                 <filename>multi-user.target</filename> (for limited
416                 console-only boots for use in embedded or server
417                 environments, or similar; a subset of
418                 graphical.target). However, it is at the discretion of
419                 the administrator to configure it as an alias to any
420                 other target unit. See
421                 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
422                 for details about these target units.</para>
423
424                 <para>Processes systemd spawns are placed in
425                 individual Linux control groups named after the unit
426                 which they belong to in the private systemd
427                 hierarchy. (see <ulink
428                 url="https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>
429                 for more information about control groups, or short
430                 "cgroups"). systemd uses this to effectively keep
431                 track of processes. Control group information is
432                 maintained in the kernel, and is accessible via the
433                 file system hierarchy (beneath
434                 <filename>/sys/fs/cgroup/systemd/</filename>), or in tools
435                 such as
436                 <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>
437                 (<command>ps xawf -eo pid,user,cgroup,args</command>
438                 is particularly useful to list all processes and the
439                 systemd units they belong to.).</para>
440
441                 <para>systemd is compatible with the SysV init system
442                 to a large degree: SysV init scripts are supported and
443                 simply read as an alternative (though limited)
444                 configuration file format. The SysV
445                 <filename>/dev/initctl</filename> interface is
446                 provided, and compatibility implementations of the
447                 various SysV client tools are available. In addition to
448                 that, various established Unix functionality such as
449                 <filename>/etc/fstab</filename> or the
450                 <filename>utmp</filename> database are
451                 supported.</para>
452
453                 <para>systemd has a minimal transaction system: if a
454                 unit is requested to start up or shut down it will add
455                 it and all its dependencies to a temporary
456                 transaction. Then, it will verify if the transaction
457                 is consistent (i.e. whether the ordering of all units
458                 is cycle-free). If it is not, systemd will try to fix
459                 it up, and removes non-essential jobs from the
460                 transaction that might remove the loop. Also, systemd
461                 tries to suppress non-essential jobs in the
462                 transaction that would stop a running service. Finally
463                 it is checked whether the jobs of the transaction
464                 contradict jobs that have already been queued, and
465                 optionally the transaction is aborted then. If all
466                 worked out and the transaction is consistent and
467                 minimized in its impact it is merged with all already
468                 outstanding jobs and added to the run
469                 queue. Effectively this means that before executing a
470                 requested operation, systemd will verify that it makes
471                 sense, fixing it if possible, and only failing if it
472                 really cannot work.</para>
473
474                 <para>Systemd contains native implementations of
475                 various tasks that need to be executed as part of the
476                 boot process. For example, it sets the hostname or
477                 configures the loopback network device. It also sets
478                 up and mounts various API file systems, such as
479                 <filename>/sys</filename> or
480                 <filename>/proc</filename>.</para>
481
482                 <para>For more information about the concepts and
483                 ideas behind systemd please refer to the <ulink
484                 url="http://0pointer.de/blog/projects/systemd.html">Original
485                 Design Document</ulink>.</para>
486
487                 <para>Note that some but not all interfaces provided
488                 by systemd are covered by the <ulink
489                 url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
490                 Stability Promise</ulink>.</para>
491
492                 <para>Units may be generated dynamically at boot and
493                 system manager reload time, for example based on other
494                 configuration files or parameters passed on the kernel
495                 command line. For details see the <ulink
496                 url="http://www.freedesktop.org/wiki/Software/systemd/Generators">Generators
497                 Specification</ulink>.</para>
498
499                 <para>Systems which invoke systemd in a container
500                 or initrd environment should implement the
501                 <ulink
502                 url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container
503                 Interface</ulink> or <ulink
504                 url="http://www.freedesktop.org/wiki/Software/systemd/InitrdInterface">initrd
505                 Interface</ulink> specifications, respectively.</para>
506         </refsect1>
507
508         <refsect1>
509                 <title>Directories</title>
510
511                 <variablelist>
512                         <varlistentry>
513                                 <term>System unit directories</term>
514
515                                 <listitem><para>The systemd system
516                                 manager reads unit configuration from
517                                 various directories. Packages that
518                                 want to install unit files shall place
519                                 them in the directory returned by
520                                 <command>pkg-config systemd
521                                 --variable=systemdsystemunitdir</command>. Other
522                                 directories checked are
523                                 <filename>/usr/local/lib/systemd/system</filename>
524                                 and
525                                 <filename>/usr/lib/systemd/system</filename>. User
526                                 configuration always takes
527                                 precedence. <command>pkg-config
528                                 systemd
529                                 --variable=systemdsystemconfdir</command>
530                                 returns the path of the system
531                                 configuration directory. Packages
532                                 should alter the content of these
533                                 directories only with the
534                                 <command>enable</command> and
535                                 <command>disable</command> commands of
536                                 the
537                                 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
538                                 tool. Full list of directories is provided in
539                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
540                                 </para></listitem>
541                         </varlistentry>
542                 </variablelist>
543
544                 <variablelist>
545                         <varlistentry>
546                                 <term>User unit directories</term>
547
548                                 <listitem><para>Similar rules apply
549                                 for the user unit
550                                 directories. However, here the <ulink
551                                 url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
552                                 Base Directory specification</ulink>
553                                 is followed to find
554                                 units. Applications should place their
555                                 unit files in the directory returned
556                                 by <command>pkg-config systemd
557                                 --variable=systemduserunitdir</command>. Global
558                                 configuration is done in the directory
559                                 reported by <command>pkg-config
560                                 systemd
561                                 --variable=systemduserconfdir</command>. The
562                                 <command>enable</command> and
563                                 <command>disable</command> commands of
564                                 the
565                                 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
566                                 tool can handle both global (i.e. for
567                                 all users) and private (for one user)
568                                 enabling/disabling of
569                                 units. Full list of directories is provided in
570                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
571                                 </para></listitem>
572                         </varlistentry>
573                 </variablelist>
574
575                 <variablelist>
576                         <varlistentry>
577                                 <term>SysV init scripts directory</term>
578
579                                 <listitem><para>The location of the
580                                 SysV init script directory varies
581                                 between distributions. If systemd
582                                 cannot find a native unit file for a
583                                 requested service, it will look for a
584                                 SysV init script of the same name
585                                 (with the
586                                 <filename>.service</filename> suffix
587                                 removed).</para></listitem>
588                         </varlistentry>
589                 </variablelist>
590
591                 <variablelist>
592                         <varlistentry>
593                                 <term>SysV runlevel link farm directory</term>
594
595                                 <listitem><para>The location of the
596                                 SysV runlevel link farm directory
597                                 varies between distributions. systemd
598                                 will take the link farm into account
599                                 when figuring out whether a service
600                                 shall be enabled. Note that a service
601                                 unit with a native unit configuration
602                                 file cannot be started by activating it
603                                 in the SysV runlevel link
604                                 farm.</para></listitem>
605                         </varlistentry>
606                 </variablelist>
607         </refsect1>
608
609         <refsect1>
610                 <title>Signals</title>
611
612                 <variablelist>
613                         <varlistentry>
614                                 <term><constant>SIGTERM</constant></term>
615
616                                 <listitem><para>Upon receiving this
617                                 signal the systemd system manager
618                                 serializes its state, reexecutes
619                                 itself and deserializes the saved
620                                 state again. This is mostly equivalent
621                                 to <command>systemctl
622                                 daemon-reexec</command>.</para>
623
624                                 <para>systemd user managers will
625                                 start the
626                                 <filename>exit.target</filename> unit
627                                 when this signal is received. This is
628                                 mostly equivalent to
629                                 <command>systemctl --user start
630                                 exit.target</command>.</para></listitem>
631                         </varlistentry>
632
633                         <varlistentry>
634                                 <term><constant>SIGINT</constant></term>
635
636                                 <listitem><para>Upon receiving this
637                                 signal the systemd system manager will
638                                 start the
639                                 <filename>ctrl-alt-del.target</filename> unit. This
640                                 is mostly equivalent to
641                                 <command>systemctl start
642                                 ctl-alt-del.target</command>.</para>
643
644                                 <para>systemd user managers
645                                 treat this signal the same way as
646                                 <constant>SIGTERM</constant>.</para></listitem>
647                         </varlistentry>
648
649                         <varlistentry>
650                                 <term><constant>SIGWINCH</constant></term>
651
652                                 <listitem><para>When this signal is
653                                 received the systemd system manager
654                                 will start the
655                                 <filename>kbrequest.target</filename>
656                                 unit. This is mostly equivalent to
657                                 <command>systemctl start
658                                 kbrequest.target</command>.</para>
659
660                                 <para>This signal is ignored by
661                                 systemd user
662                                 managers.</para></listitem>
663                         </varlistentry>
664
665                         <varlistentry>
666                                 <term><constant>SIGPWR</constant></term>
667
668                                 <listitem><para>When this signal is
669                                 received the systemd manager
670                                 will start the
671                                 <filename>sigpwr.target</filename>
672                                 unit. This is mostly equivalent to
673                                 <command>systemctl start
674                                 sigpwr.target</command>.</para></listitem>
675                         </varlistentry>
676
677                         <varlistentry>
678                                 <term><constant>SIGUSR1</constant></term>
679
680                                 <listitem><para>When this signal is
681                                 received the systemd manager will try
682                                 to reconnect to the D-Bus
683                                 bus.</para></listitem>
684                         </varlistentry>
685
686                         <varlistentry>
687                                 <term><constant>SIGUSR2</constant></term>
688
689                                 <listitem><para>When this signal is
690                                 received the systemd manager will log
691                                 its complete state in human readable
692                                 form. The data logged is the same as
693                                 printed by <command>systemctl
694                                 dump</command>.</para></listitem>
695                         </varlistentry>
696
697                         <varlistentry>
698                                 <term><constant>SIGHUP</constant></term>
699
700                                 <listitem><para>Reloads the complete
701                                 daemon configuration. This is mostly
702                                 equivalent to <command>systemctl
703                                 daemon-reload</command>.</para></listitem>
704                         </varlistentry>
705
706                         <varlistentry>
707                                 <term><constant>SIGRTMIN+0</constant></term>
708
709                                 <listitem><para>Enters default mode, starts the
710                                 <filename>default.target</filename>
711                                 unit. This is mostly equivalent to
712                                 <command>systemctl start
713                                 default.target</command>.</para></listitem>
714                         </varlistentry>
715
716                         <varlistentry>
717                                 <term><constant>SIGRTMIN+1</constant></term>
718
719                                 <listitem><para>Enters rescue mode,
720                                 starts the
721                                 <filename>rescue.target</filename>
722                                 unit. This is mostly equivalent to
723                                 <command>systemctl isolate
724                                 rescue.target</command>.</para></listitem>
725                         </varlistentry>
726
727                         <varlistentry>
728                                 <term><constant>SIGRTMIN+2</constant></term>
729
730                                 <listitem><para>Enters emergency mode,
731                                 starts the
732                                 <filename>emergency.service</filename>
733                                 unit. This is mostly equivalent to
734                                 <command>systemctl isolate
735                                 emergency.service</command>.</para></listitem>
736                         </varlistentry>
737
738                         <varlistentry>
739                                 <term><constant>SIGRTMIN+3</constant></term>
740
741                                 <listitem><para>Halts the machine,
742                                 starts the
743                                 <filename>halt.target</filename>
744                                 unit. This is mostly equivalent to
745                                 <command>systemctl start
746                                 halt.target</command>.</para></listitem>
747                         </varlistentry>
748
749                         <varlistentry>
750                                 <term><constant>SIGRTMIN+4</constant></term>
751
752                                 <listitem><para>Powers off the machine,
753                                 starts the
754                                 <filename>poweroff.target</filename>
755                                 unit. This is mostly equivalent to
756                                 <command>systemctl start
757                                 poweroff.target</command>.</para></listitem>
758                         </varlistentry>
759
760                         <varlistentry>
761                                 <term><constant>SIGRTMIN+5</constant></term>
762
763                                 <listitem><para>Reboots the machine,
764                                 starts the
765                                 <filename>reboot.target</filename>
766                                 unit. This is mostly equivalent to
767                                 <command>systemctl start
768                                 reboot.target</command>.</para></listitem>
769                         </varlistentry>
770
771                         <varlistentry>
772                                 <term><constant>SIGRTMIN+6</constant></term>
773
774                                 <listitem><para>Reboots the machine via kexec,
775                                 starts the
776                                 <filename>kexec.target</filename>
777                                 unit. This is mostly equivalent to
778                                 <command>systemctl start
779                                 kexec.target</command>.</para></listitem>
780                         </varlistentry>
781
782                         <varlistentry>
783                                 <term><constant>SIGRTMIN+13</constant></term>
784
785                                 <listitem><para>Immediately halts the machine.</para></listitem>
786                         </varlistentry>
787
788                         <varlistentry>
789                                 <term><constant>SIGRTMIN+14</constant></term>
790
791                                 <listitem><para>Immediately powers off the machine.</para></listitem>
792                         </varlistentry>
793
794                         <varlistentry>
795                                 <term><constant>SIGRTMIN+15</constant></term>
796
797                                 <listitem><para>Immediately reboots the machine.</para></listitem>
798                         </varlistentry>
799
800                         <varlistentry>
801                                 <term><constant>SIGRTMIN+16</constant></term>
802
803                                 <listitem><para>Immediately reboots the machine with kexec.</para></listitem>
804                         </varlistentry>
805
806                         <varlistentry>
807                                 <term><constant>SIGRTMIN+20</constant></term>
808
809                                 <listitem><para>Enables display of
810                                 status messages on the console, as
811                                 controlled via
812                                 <varname>systemd.show_status=1</varname>
813                                 on the kernel command
814                                 line.</para></listitem>
815                         </varlistentry>
816
817                         <varlistentry>
818                                 <term><constant>SIGRTMIN+21</constant></term>
819
820                                 <listitem><para>Disables display of
821                                 status messages on the console, as
822                                 controlled via
823                                 <varname>systemd.show_status=0</varname>
824                                 on the kernel command
825                                 line.</para></listitem>
826                         </varlistentry>
827
828                         <varlistentry>
829                                 <term><constant>SIGRTMIN+22</constant></term>
830                                 <term><constant>SIGRTMIN+23</constant></term>
831
832                                 <listitem><para>Sets the log level to
833                                 <literal>debug</literal>
834                                 (or <literal>info</literal> on
835                                 <constant>SIGRTMIN+23</constant>), as
836                                 controlled via
837                                 <varname>systemd.log_level=debug</varname>
838                                 (or <varname>systemd.log_level=info</varname>
839                                 on <constant>SIGRTMIN+23</constant>) on
840                                 the kernel command
841                                 line.</para></listitem>
842                         </varlistentry>
843
844                         <varlistentry>
845                                 <term><constant>SIGRTMIN+24</constant></term>
846
847                                 <listitem><para>Immediately exits the
848                                 manager (only available for --user
849                                 instances).</para></listitem>
850                         </varlistentry>
851
852                         <varlistentry>
853                                 <term><constant>SIGRTMIN+26</constant></term>
854                                 <term><constant>SIGRTMIN+27</constant></term>
855                                 <term><constant>SIGRTMIN+28</constant></term>
856                                 <term><constant>SIGRTMIN+29</constant></term>
857
858                                 <listitem><para>Sets the log level to
859                                 <literal>journal-or-kmsg</literal>
860                                 (or <literal>console</literal> on
861                                 <constant>SIGRTMIN+27</constant>,
862                                 <literal>kmsg</literal> on
863                                 <constant>SIGRTMIN+28</constant>,
864                                 or <literal>syslog-or-kmsg</literal>
865                                 on <constant>SIGRTMIN+29</constant>), as
866                                 controlled via
867                                 <varname>systemd.log_target=journal-or-kmsg</varname>
868                                 (or <varname>systemd.log_target=console</varname>
869                                 on <constant>SIGRTMIN+27</constant>,
870                                 <varname>systemd.log_target=kmsg</varname>
871                                 on <constant>SIGRTMIN+28</constant>,
872                                 or
873                                 <varname>systemd.log_target=syslog-or-kmsg</varname>
874                                 on <constant>SIGRTMIN+29</constant>) on
875                                 the kernel command
876                                 line.</para></listitem>
877                         </varlistentry>
878                 </variablelist>
879         </refsect1>
880
881         <refsect1>
882                 <title>Environment</title>
883
884                 <variablelist class='environment-variables'>
885                         <varlistentry>
886                                 <term><varname>$SYSTEMD_LOG_LEVEL</varname></term>
887                                 <listitem><para>systemd reads the
888                                 log level from this environment
889                                 variable. This can be overridden with
890                                 <option>--log-level=</option>.</para></listitem>
891                         </varlistentry>
892
893                         <varlistentry>
894                                 <term><varname>$SYSTEMD_LOG_TARGET</varname></term>
895                                 <listitem><para>systemd reads the
896                                 log target from this environment
897                                 variable. This can be overridden with
898                                 <option>--log-target=</option>.</para></listitem>
899                         </varlistentry>
900
901                         <varlistentry>
902                                 <term><varname>$SYSTEMD_LOG_COLOR</varname></term>
903                                 <listitem><para>Controls whether
904                                 systemd highlights important log
905                                 messages. This can be overridden with
906                                 <option>--log-color=</option>.</para></listitem>
907                         </varlistentry>
908
909                         <varlistentry>
910                                 <term><varname>$SYSTEMD_LOG_LOCATION</varname></term>
911                                 <listitem><para>Controls whether
912                                 systemd prints the code location along
913                                 with log messages. This can be
914                                 overridden with
915                                 <option>--log-location=</option>.</para></listitem>
916                         </varlistentry>
917
918                         <varlistentry>
919                                 <term><varname>$XDG_CONFIG_HOME</varname></term>
920                                 <term><varname>$XDG_CONFIG_DIRS</varname></term>
921                                 <term><varname>$XDG_DATA_HOME</varname></term>
922                                 <term><varname>$XDG_DATA_DIRS</varname></term>
923
924                                 <listitem><para>The systemd user
925                                 manager uses these variables in
926                                 accordance to the <ulink
927                                 url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
928                                 Base Directory specification</ulink>
929                                 to find its configuration.</para></listitem>
930                         </varlistentry>
931
932                         <varlistentry>
933                                 <term><varname>$SYSTEMD_UNIT_PATH</varname></term>
934
935                                 <listitem><para>Controls where systemd
936                                 looks for unit
937                                 files.</para></listitem>
938                         </varlistentry>
939
940                         <varlistentry>
941                                 <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term>
942
943                                 <listitem><para>Controls where systemd
944                                 looks for SysV init scripts.</para></listitem>
945                         </varlistentry>
946
947                         <varlistentry>
948                                 <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term>
949
950                                 <listitem><para>Controls where systemd
951                                 looks for SysV init script runlevel link
952                                 farms.</para></listitem>
953                         </varlistentry>
954
955                         <varlistentry>
956                                 <term><varname>$LISTEN_PID</varname></term>
957                                 <term><varname>$LISTEN_FDS</varname></term>
958
959                                 <listitem><para>Set by systemd for
960                                 supervised processes during
961                                 socket-based activation. See
962                                 <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
963                                 for more information.
964                                 </para></listitem>
965                         </varlistentry>
966
967                         <varlistentry>
968                                 <term><varname>$NOTIFY_SOCKET</varname></term>
969
970                                 <listitem><para>Set by systemd for
971                                 supervised processes for status and
972                                 start-up completion notification. See
973                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
974                                 for more information.
975                                 </para></listitem>
976                         </varlistentry>
977                 </variablelist>
978         </refsect1>
979
980         <refsect1>
981                 <title>Kernel Command Line</title>
982
983                 <para>When run as system instance systemd parses a
984                 number of kernel command line
985                 arguments<footnote><para>If run inside a Linux
986                 container these arguments may be passed as command
987                 line arguments to systemd itself, next to any of the
988                 command line options listed in the Options section
989                 above. If run outside of Linux containers, these
990                 arguments are parsed from
991                 <filename>/proc/cmdline</filename>
992                 instead.</para></footnote>:</para>
993
994                 <variablelist class='kernel-commandline-options'>
995                         <varlistentry>
996                                 <term><varname>systemd.unit=</varname></term>
997                                 <term><varname>rd.systemd.unit=</varname></term>
998
999                                 <listitem><para>Overrides the unit to
1000                                 activate on boot. Defaults to
1001                                 <filename>default.target</filename>. This
1002                                 may be used to temporarily boot into a
1003                                 different boot unit, for example
1004                                 <filename>rescue.target</filename> or
1005                                 <filename>emergency.service</filename>. See
1006                                 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1007                                 for details about these units. The
1008                                 option prefixed with
1009                                 <literal>rd.</literal> is honored
1010                                 only in the initial RAM disk (initrd),
1011                                 while the one that is not prefixed only
1012                                 in the main system.</para></listitem>
1013                         </varlistentry>
1014
1015                         <varlistentry>
1016                                 <term><varname>systemd.dump_core=</varname></term>
1017
1018                                 <listitem><para>Takes a boolean
1019                                 argument. If <option>true</option>,
1020                                 systemd dumps core when it
1021                                 crashes. Otherwise, no core dump is
1022                                 created. Defaults to
1023                                 <option>true</option>.</para></listitem>
1024                         </varlistentry>
1025
1026                         <varlistentry>
1027                                 <term><varname>systemd.crash_shell=</varname></term>
1028
1029                                 <listitem><para>Takes a boolean
1030                                 argument. If <option>true</option>,
1031                                 systemd spawns a shell when it
1032                                 crashes. Otherwise, no shell is
1033                                 spawned. Defaults to
1034                                 <option>false</option>, for security
1035                                 reasons, as the shell is not protected
1036                                 by any password
1037                                 authentication.</para></listitem>
1038                         </varlistentry>
1039
1040                         <varlistentry>
1041                                 <term><varname>systemd.crash_chvt=</varname></term>
1042
1043                                 <listitem><para>Takes an integer
1044                                 argument. If positive systemd
1045                                 activates the specified virtual
1046                                 terminal when it crashes. Defaults to
1047                                 <constant>-1</constant>.</para></listitem>
1048                         </varlistentry>
1049
1050                         <varlistentry>
1051                                 <term><varname>systemd.confirm_spawn=</varname></term>
1052
1053                                 <listitem><para>Takes a boolean
1054                                 argument. If <option>true</option>,
1055                                 asks for confirmation when spawning
1056                                 processes. Defaults to
1057                                 <option>false</option>.</para></listitem>
1058                         </varlistentry>
1059
1060                         <varlistentry>
1061                                 <term><varname>systemd.show_status=</varname></term>
1062
1063                                 <listitem><para>Takes a boolean
1064                                 argument. If <option>true</option>,
1065                                 shows terse service status updates on
1066                                 the console during bootup. Defaults to
1067                                 <option>true</option>, unless
1068                                 <option>quiet</option> is passed as
1069                                 kernel command line option in which
1070                                 case it defaults to
1071                                 <option>false</option>.</para></listitem>
1072                         </varlistentry>
1073
1074                         <varlistentry>
1075                                 <term><varname>systemd.log_target=</varname></term>
1076                                 <term><varname>systemd.log_level=</varname></term>
1077                                 <term><varname>systemd.log_color=</varname></term>
1078                                 <term><varname>systemd.log_location=</varname></term>
1079
1080                                 <listitem><para>Controls log output,
1081                                 with the same effect as the
1082                                 <varname>$SYSTEMD_LOG_TARGET</varname>, <varname>$SYSTEMD_LOG_LEVEL</varname>, <varname>$SYSTEMD_LOG_COLOR</varname>, <varname>$SYSTEMD_LOG_LOCATION</varname>
1083                                 environment variables described above.</para></listitem>
1084                         </varlistentry>
1085
1086                         <varlistentry>
1087                                 <term><varname>systemd.default_standard_output=</varname></term>
1088                                 <term><varname>systemd.default_standard_error=</varname></term>
1089                                 <listitem><para>Controls default
1090                                 standard output and error output for
1091                                 services, with the same effect as the
1092                                 <option>--default-standard-output=</option>
1093                                 and <option>--default-standard-error=</option>
1094                                 command line arguments described
1095                                 above, respectively.</para></listitem>
1096                         </varlistentry>
1097
1098                         <varlistentry>
1099                                 <term><varname>systemd.setenv=</varname></term>
1100
1101                                 <listitem><para>Takes a string
1102                                 argument in the form VARIABLE=VALUE.
1103                                 May be used to set default environment
1104                                 variables to add to forked child processes.
1105                                 May be used more than once to set multiple
1106                                 variables.</para></listitem>
1107                         </varlistentry>
1108
1109                         <varlistentry>
1110                                 <term><varname>quiet</varname></term>
1111
1112                                 <listitem><para>Turn off
1113                                 status output at boot, much like
1114                                 <varname>systemd.show_status=false</varname>
1115                                 would. Note that this option is also
1116                                 read by the kernel itself and disables
1117                                 kernel log output. Passing this option
1118                                 hence turns off the usual output from
1119                                 both the system manager and the kernel.
1120                                 </para></listitem>
1121                         </varlistentry>
1122
1123                         <varlistentry>
1124                                 <term><varname>debug</varname></term>
1125
1126                                 <listitem><para>Turn on debugging
1127                                 output. This is equivalent to
1128                                 <varname>systemd.log_level=debug</varname>.
1129                                 Note that this option is also read by
1130                                 the kernel itself and enables kernel
1131                                 debug output.  Passing this option
1132                                 hence turns on the debug output from
1133                                 both the system manager and the
1134                                 kernel.</para></listitem>
1135                         </varlistentry>
1136
1137                         <varlistentry>
1138                                 <term><varname>-b</varname></term>
1139                                 <term><varname>emergency</varname></term>
1140
1141                                 <listitem><para>Boot into emergency
1142                                 mode. This is equivalent to
1143                                 <varname>systemd.unit=emergency.target</varname>
1144                                 and provided for compatibility
1145                                 reasons and to be easier to type.</para></listitem>
1146                         </varlistentry>
1147
1148                         <varlistentry>
1149                                 <term><varname>single</varname></term>
1150                                 <term><varname>s</varname></term>
1151                                 <term><varname>S</varname></term>
1152                                 <term><varname>1</varname></term>
1153
1154                                 <listitem><para>Boot into rescue
1155                                 mode. This is equivalent to
1156                                 <varname>systemd.unit=rescue.target</varname>
1157                                 and provided for compatibility reasons
1158                                 and to be easier to
1159                                 type.</para></listitem>
1160                         </varlistentry>
1161
1162                         <varlistentry>
1163                                 <term><varname>2</varname></term>
1164                                 <term><varname>3</varname></term>
1165                                 <term><varname>4</varname></term>
1166                                 <term><varname>5</varname></term>
1167
1168                                 <listitem><para>Boot into the
1169                                 specified legacy SysV runlevel. These
1170                                 are equivalent to
1171                                 <varname>systemd.unit=runlevel2.target</varname>,
1172                                 <varname>systemd.unit=runlevel3.target</varname>,
1173                                 <varname>systemd.unit=runlevel4.target</varname>,
1174                                 and <varname>systemd.unit=runlevel5.target</varname>, respectively,
1175                                 and provided for compatibility reasons
1176                                 and to be easier to
1177                                 type.</para></listitem>
1178                         </varlistentry>
1179
1180                         <varlistentry>
1181                                 <term><varname>locale.LANG=</varname></term>
1182                                 <term><varname>locale.LANGUAGE=</varname></term>
1183                                 <term><varname>locale.LC_CTYPE=</varname></term>
1184                                 <term><varname>locale.LC_NUMERIC=</varname></term>
1185                                 <term><varname>locale.LC_TIME=</varname></term>
1186                                 <term><varname>locale.LC_COLLATE=</varname></term>
1187                                 <term><varname>locale.LC_MONETARY=</varname></term>
1188                                 <term><varname>locale.LC_MESSAGES=</varname></term>
1189                                 <term><varname>locale.LC_PAPER=</varname></term>
1190                                 <term><varname>locale.LC_NAME=</varname></term>
1191                                 <term><varname>locale.LC_ADDRESS=</varname></term>
1192                                 <term><varname>locale.LC_TELEPHONE=</varname></term>
1193                                 <term><varname>locale.LC_MEASUREMENT=</varname></term>
1194                                 <term><varname>locale.LC_IDENTIFICATION=</varname></term>
1195
1196                                 <listitem><para>Set the system locale
1197                                 to use. This overrides the settings in
1198                                 <filename>/etc/locale.conf</filename>. For
1199                                 more information see
1200                                 <citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1201                                 and
1202                                 <citerefentry><refentrytitle>locale</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
1203                                 </para></listitem>
1204                         </varlistentry>
1205                 </variablelist>
1206
1207                 <para>For other kernel command line parameters
1208                 understood by components of the core OS, please refer
1209                 to
1210                 <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
1211         </refsect1>
1212
1213         <refsect1>
1214                 <title>Sockets and FIFOs</title>
1215
1216                 <variablelist>
1217                         <varlistentry>
1218                                 <term><filename>/run/systemd/notify</filename></term>
1219
1220                                 <listitem><para>Daemon status
1221                                 notification socket. This is an
1222                                 <constant>AF_UNIX</constant> datagram socket and is used to
1223                                 implement the daemon notification
1224                                 logic as implemented by
1225                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
1226
1227                         </varlistentry>
1228
1229                         <varlistentry>
1230                                 <term><filename>/run/systemd/shutdownd</filename></term>
1231
1232                                 <listitem><para>Used internally by the
1233                                 <citerefentry><refentrytitle>shutdown</refentrytitle><manvolnum>8</manvolnum></citerefentry>
1234                                 tool to implement delayed
1235                                 shutdowns. This is an <constant>AF_UNIX</constant> datagram
1236                                 socket.</para></listitem>
1237                         </varlistentry>
1238
1239                         <varlistentry>
1240                                 <term><filename>/run/systemd/private</filename></term>
1241
1242                                 <listitem><para>Used internally as
1243                                 communication channel between
1244                                 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
1245                                 and the systemd process. This is an
1246                                 <constant>AF_UNIX</constant> stream socket. This interface
1247                                 is private to systemd and should not
1248                                 be used in external
1249                                 projects.</para></listitem>
1250                         </varlistentry>
1251
1252                         <varlistentry>
1253                                 <term><filename>/dev/initctl</filename></term>
1254
1255                                 <listitem><para>Limited compatibility
1256                                 support for the SysV client interface,
1257                                 as implemented by the
1258                                 <filename>systemd-initctl.service</filename>
1259                                 unit. This is a named pipe in the file
1260                                 system. This interface is obsolete and
1261                                 should not be used in new
1262                                 applications.</para></listitem>
1263                         </varlistentry>
1264                 </variablelist>
1265         </refsect1>
1266
1267         <refsect1>
1268                 <title>See Also</title>
1269                 <para>
1270                         The <ulink url="http://www.freedesktop.org/wiki/Software/systemd/">systemd Homepage</ulink>,
1271                         <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1272                         <citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1273                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1274                         <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1275                         <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1276                         <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1277                         <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
1278                         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1279                         <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1280                         <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1281                         <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1282                         <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1283                         <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1284                 </para>
1285         </refsect1>
1286
1287 </refentry>