chapter06/systemd.xml.next

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   4   <!ENTITY % general-entities SYSTEM "../general.ent">
   5   %general-entities;
   6 ]>
   7
   8 <sect1 id="ch-system-systemd" role="wrap">
   9   <?dbhtml filename="systemd.html"?>
  10
  11   <sect1info condition="script">
  12     <productname>systemd</productname>
  13     <productnumber>&systemd-version;</productnumber>
  14     <address>&systemd-url;</address>
  15   </sect1info>
  16
  17   <title>Systemd-&systemd-version;</title>
  18
  19   <indexterm zone="ch-system-systemd">
  20     <primary sortas="a-systemd">systemd</primary>
  21   </indexterm>
  22
  23   <sect2 role="package">
  24     <title/>
  25
  26     <para>The systemd package contains programs for controlling the startup,
  27     running, and shutdown of the system.</para>
  28
  29     <segmentedlist>
  30       <segtitle>&buildtime;</segtitle>
  31       <segtitle>&diskspace;</segtitle>
  32
  33       <seglistitem>
  34         <seg>&systemd-ch6-sbu;</seg>
  35         <seg>&systemd-ch6-du;</seg>
  36       </seglistitem>
  37     </segmentedlist>
  38   </sect2>
  39
  40   <sect2 role="installation">
  41     <title>Installation of systemd</title>
  42
  43     <para>First, create a file to allow systemd to build when using Util-Linux
  44     built in Chapter 5 and disable LTO by default:</para>
  45
  46 <screen><userinput remap="pre">cat &gt; config.cache &lt;&lt; "EOF"
  47 <literal>KILL=/bin/kill
  48 HAVE_BLKID=1
  49 BLKID_LIBS="-lblkid"
  50 BLKID_CFLAGS="-I/tools/include/blkid"
  51 cc_cv_CFLAGS__flto=no</literal>
  52 EOF</userinput></screen>
  53
  54     <para>LTO is disabled by default because it causes <command>systemd</command>
  55     and other auxiliary programs to link to <filename
  56     class="libraryfile">libgcc_s.so</filename>, slows the build down and makes the
  57     compiled code larger.</para>
  58
  59     <para>Additionally, fix a build error when using Util-Linux built in
  60     Chapter 5:</para>
  61
  62 <screen><userinput remap="pre">sed -i "s:blkid/::" $(grep -rl "blkid/blkid.h")</userinput></screen>
  63
  64     <para>Apply a patch so that compat <command>pkg-config</command> files get
  65     installed without installing compat libs which are useless on LFS:</para>
  66
  67 <screen><userinput remap="pre">patch -Np1 -i ../&systemd-compat-patch;</userinput></screen>
  68
  69     <para>Prepare systemd for compilation:</para>
  70
  71 <screen><userinput remap="configure">./configure --prefix=/usr                                           \
  72             --sysconfdir=/etc                                       \
  73             --localstatedir=/var                                    \
  74             --config-cache                                          \
  75             --with-rootprefix=                                      \
  76             --with-rootlibdir=/lib                                  \
  77             --enable-split-usr                                      \
  78             --disable-gudev                                         \
  79             --disable-firstboot                                     \
  80             --disable-ldconfig                                      \
  81             --disable-sysusers                                      \
  82             --without-python                                        \
  83             --docdir=/usr/share/doc/systemd-&systemd-version;                     \
  84             --with-dbuspolicydir=/etc/dbus-1/system.d               \
  85             --with-dbusinterfacedir=/usr/share/dbus-1/interfaces    \
  86             --with-dbussessionservicedir=/usr/share/dbus-1/services \
  87             --with-dbussystemservicedir=/usr/share/dbus-1/system-services</userinput></screen>
  88
  89     <variablelist>
  90       <title>The meaning of the configure options:</title>
  91
  92       <varlistentry>
  93         <term><parameter>--config-cache</parameter></term>
  94         <listitem>
  95           <para>This switch tells the build system to use
  96           the <filename>config.cache</filename> file which
  97           was created earlier.</para>
  98         </listitem>
  99       </varlistentry>
 100
 101       <varlistentry>
 102         <term><parameter>--with-root*</parameter></term>
 103         <listitem>
 104           <para>These switches ensure that core programs and
 105           shared libraries are installed in the subdirectories
 106           of the root partition.</para>
 107         </listitem>
 108       </varlistentry>
 109
 110       <varlistentry>
 111         <term><parameter>--enable-split-usr</parameter></term>
 112         <listitem>
 113           <para>This switch ensures that systemd will work on
 114           systems where /bin, /lib and /sbin directories are not
 115           symlinks to their /usr counterparts.</para>
 116         </listitem>
 117       </varlistentry>
 118
 119       <varlistentry>
 120         <term><parameter>--disable-gudev --without-python</parameter></term>
 121         <listitem>
 122           <para>These switches disable optional features because
 123           LFS does not provide their dependencies.</para>
 124         </listitem>
 125       </varlistentry>
 126
 127       <varlistentry>
 128         <term><parameter>--disable-firstboot</parameter></term>
 129         <listitem>
 130           <para>This switch prevents installation of systemd
 131           services responsible for setting up the system for
 132           the first time. They are not useful for LFS because
 133           everything is done manually.</para>
 134         </listitem>
 135       </varlistentry>
 136
 137       <varlistentry>
 138         <term><parameter>--disable-ldconfig</parameter></term>
 139         <listitem>
 140           <para>This switch prevents installation of a systemd
 141           unit that runs <command>ldconfig</command> at
 142           boot, making the boot time longer. Remove it if the
 143           described feature is desired, even though it's not
 144           useful for source distributions such as LFS.</para>
 145         </listitem>
 146       </varlistentry>
 147
 148       <varlistentry>
 149         <term><parameter>--disable-sysusers</parameter></term>
 150         <listitem>
 151           <para>This switch prevents installation of systemd
 152           services responsible for setting up the
 153           <filename>/etc/group</filename> and
 154           <filename>/etc/passwd</filename> files. Both files
 155           were created early in this chapter.</para>
 156         </listitem>
 157       </varlistentry>
 158
 159       <varlistentry>
 160         <term><parameter>--with-dbus*</parameter></term>
 161         <listitem>
 162           <para>These switches ensure that D-Bus configuration files
 163           get installed in the correct locations.</para>
 164         </listitem>
 165       </varlistentry>
 166
 167     </variablelist>
 168
 169     <para>Compile the package:</para>
 170
 171 <screen><userinput remap="make">make LIBRARY_PATH=/tools/lib</userinput></screen>
 172
 173     <para>If you are going to run the test suite, first prevent a few test
 174     cases from running because they fail in a chroot environment:</para>
 175
 176 <screen><userinput remap="test">sed -e "s:test/udev-test.pl::g"             \
 177     -e "s:test-bus-cleanup\$(EXEEXT) ::g"   \
 178     -e "s:test-bus-gvariant\$(EXEEXT) ::g"  \
 179     -e "s:test-dhcp6-client\$(EXEEXT) ::g"  \
 180     -e "s:test-journal-flush\$(EXEEXT) ::g" \
 181     -e "s:test-path-util\$(EXEEXT) ::g"     \
 182     -e "s:test-sched-prio\$(EXEEXT) ::g"    \
 183     -e "s:test-strv\$(EXEEXT) ::g"          \
 184     -i Makefile</userinput></screen>
 185
 186     <para>To test the results, issue:</para>
 187
 188 <screen><userinput remap="test">make check</userinput></screen>
 189
 190     <para>Install the package:</para>
 191
 192 <screen><userinput remap="install">make LD_LIBRARY_PATH=/tools/lib install</userinput></screen>
 193
 194     <para>Move NSS libraries to <filename class="directory">/lib</filename>:</para>
 195
 196 <screen><userinput remap="install">mv -v /usr/lib/libnss_{myhostname,mymachines,resolve}.so.2 /lib</userinput></screen>
 197
 198     <para>Remove an unnecessary directory:</para>
 199
 200 <screen><userinput remap="install">rm -rfv /usr/lib/rpm</userinput></screen>
 201
 202     <para>Create the Sysvinit compatibility symlinks, so systemd is used
 203     as the default init system:</para>
 204
 205 <screen><userinput remap="install">for tool in runlevel reboot shutdown poweroff halt telinit; do
 206      ln -sfv ../bin/systemctl /sbin/${tool}
 207 done
 208 ln -sfv ../lib/systemd/systemd /sbin/init</userinput></screen>
 209
 210     <para>Remove a reference to a non-existent group:</para>
 211
 212 <screen><userinput remap="install">sed -i "s:0775 root lock:0755 root root:g" /usr/lib/tmpfiles.d/legacy.conf</userinput></screen>
 213
 214     <para>Create the <filename>/etc/machine-id</filename> file needed by
 215     Journald:</para>
 216
 217 <screen><userinput remap="install">systemd-machine-id-setup</userinput></screen>
 218
 219   </sect2>
 220
 221   <sect2 id="contents-systemd" role="content">
 222     <title>Contents of systemd</title>
 223
 224     <segmentedlist>
 225       <segtitle>Installed programs</segtitle>
 226       <segtitle>Installed libraries</segtitle>
 227       <segtitle>Installed directories</segtitle>
 228
 229       <seglistitem>
 230         <seg>bootctl, busctl, coredumpctl, halt, hostnamectl, init, journalctl,
 231         kernel-install, localectl, loginctl, machinectl, networkctl, poweroff,
 232         reboot, runlevel, shutdown, systemctl, systemd-analyze,
 233         systemd-ask-password, systemd-cat, systemd-cgls, systemd-cgtop,
 234         systemd-delta, systemd-detect-virt, systemd-escape,<!-- systemd-firstboot, -->
 235         systemd-inhibit, systemd-machine-id-setup, systemd-notify, systemd-nspawn,
 236         systemd-path, systemd-run, systemd-stdio-bridge,<!-- systemd-sysusers, -->
 237         systemd-tmpfiles, systemd-tty-ask-password-agent, telinit, timedatectl,
 238         and udevadm</seg>
 239         <seg>libnss_myhostname.so.2, libnss_mymachines.so.2, libnss_resolve.so.2,
 240         libsystemd.so, libudev.so</seg>
 241         <seg>/etc/binfmt.d, /etc/init.d, /etc/kernel, /etc/modules-load.d,
 242         /etc/sysctl.d, /etc/systemd, /etc/tmpfiles.d, /etc/udev,
 243         /etc/xdg/systemd, /lib/systemd, /lib/udev, /usr/include/systemd,
 244         /usr/lib/binfmt.d, /usr/lib/kernel, /usr/lib/modules-load.d,
 245         /usr/lib/sysctl.d, /usr/lib/systemd,<!-- /usr/lib/sysusers.d, -->
 246         /usr/lib/tmpfiles.d, /usr/share/doc/systemd-&systemd-version;,
 247         /usr/share/factory, /usr/share/systemd, /var/lib/systemd,
 248         /var/log/journal</seg>
 249       </seglistitem>
 250     </segmentedlist>
 251
 252     <variablelist>
 253       <bridgehead renderas="sect3">Short Descriptions</bridgehead>
 254       <?dbfo list-presentation="list"?>
 255       <?dbhtml list-presentation="table"?>
 256
 257       <varlistentry id="bootctl">
 258         <term><command>bootctl</command></term>
 259         <listitem>
 260           <para>used to query the firmware and boot manager settings.</para>
 261           <indexterm zone="ch-system-systemd bootctl">
 262             <primary sortas="b-bootctl">bootctl</primary>
 263           </indexterm>
 264         </listitem>
 265       </varlistentry>
 266
 267       <varlistentry id="busctl">
 268         <term><command>busctl</command></term>
 269         <listitem>
 270           <para>Used to introspect and monitor the D-Bus bus.</para>
 271           <indexterm zone="ch-system-systemd busctl">
 272             <primary sortas="b-busctl">busctl</primary>
 273           </indexterm>
 274         </listitem>
 275       </varlistentry>
 276
 277       <varlistentry id="coredumpctl">
 278         <term><command>coredumpctl</command></term>
 279         <listitem>
 280           <para>Used to retrieve coredumps from the systemd Journal</para>
 281           <indexterm zone="ch-system-systemd coredumpctl">
 282             <primary sortas="b-coredumpctl">coredumpctl</primary>
 283           </indexterm>
 284         </listitem>
 285       </varlistentry>
 286
 287       <varlistentry id="halt">
 288         <term><command>halt</command></term>
 289         <listitem>
 290           <para>Normally invokes <command>shutdown</command> with the
 291           <parameter>-h</parameter> option, except when already in run-level 0,
 292           then it tells the kernel to halt the system; it notes in the
 293           file <filename>/var/log/wtmp</filename> that the system is being
 294           brought down.</para>
 295           <indexterm zone="ch-system-systemd halt">
 296             <primary sortas="b-halt">halt</primary>
 297           </indexterm>
 298         </listitem>
 299       </varlistentry>
 300
 301       <varlistentry id="hostnamectl">
 302         <term><command>hostnamectl</command></term>
 303         <listitem>
 304           <para>Used to query and change the system hostname and related
 305           settings.</para>
 306           <indexterm zone="ch-system-systemd hostnamectl">
 307             <primary sortas="b-hostnamectl">hostnamectl</primary>
 308           </indexterm>
 309         </listitem>
 310       </varlistentry>
 311
 312       <varlistentry id="init">
 313         <term><command>init</command></term>
 314         <listitem>
 315           <para>The first process to be started when the kernel has initialized
 316           the hardware which takes over the boot process and starts all the
 317           proceses it is instructed to.</para>
 318           <indexterm zone="ch-system-systemd init">
 319             <primary sortas="b-init">init</primary>
 320           </indexterm>
 321         </listitem>
 322       </varlistentry>
 323
 324       <varlistentry id="journalctl">
 325         <term><command>journalctl</command></term>
 326         <listitem>
 327           <para>Used to query the contents of the systemd Journal.</para>
 328           <indexterm zone="ch-system-systemd journalctl">
 329             <primary sortas="b-journalctl">journalctl</primary>
 330           </indexterm>
 331         </listitem>
 332       </varlistentry>
 333
 334       <varlistentry id="kernel-install">
 335         <term><command>kernel-install</command></term>
 336         <listitem>
 337           <para>Used to add and remove kernel and initramfs images to and
 338           from /boot.</para>
 339           <indexterm zone="ch-system-systemd kernel-install">
 340             <primary sortas="b-kernel-install">kernel-install</primary>
 341           </indexterm>
 342         </listitem>
 343       </varlistentry>
 344
 345       <varlistentry id="localectl">
 346         <term><command>localectl</command></term>
 347         <listitem>
 348           <para>Used to query and change the system locale and keyboard layout
 349           settings.</para>
 350           <indexterm zone="ch-system-systemd localectl">
 351             <primary sortas="b-localectl">localectl</primary>
 352           </indexterm>
 353         </listitem>
 354       </varlistentry>
 355
 356       <varlistentry id="loginctl">
 357         <term><command>loginctl</command></term>
 358         <listitem>
 359           <para>Used to introspect and control the state of the systemd Login
 360           Manager.</para>
 361           <indexterm zone="ch-system-systemd loginctl">
 362             <primary sortas="b-loginctl">loginctl</primary>
 363           </indexterm>
 364         </listitem>
 365       </varlistentry>
 366
 367       <varlistentry id="machinectl">
 368         <term><command>machinectl</command></term>
 369         <listitem>
 370           <para>Used to introspect and control the state of the systemd Virtual
 371           Machine and Container Registration Manager</para>
 372           <indexterm zone="ch-system-systemd machinectl">
 373             <primary sortas="b-machinectl">machinectl</primary>
 374           </indexterm>
 375         </listitem>
 376       </varlistentry>
 377
 378       <varlistentry id="poweroff">
 379         <term><command>poweroff</command></term>
 380         <listitem>
 381           <para>Tells the kernel to halt the system and switch off the computer
 382           (see <command>halt</command>).</para>
 383           <indexterm zone="ch-system-systemd poweroff">
 384             <primary sortas="b-poweroff">poweroff</primary>
 385           </indexterm>
 386         </listitem>
 387       </varlistentry>
 388
 389       <varlistentry id="reboot">
 390         <term><command>reboot</command></term>
 391         <listitem>
 392           <para>Tells the kernel to reboot the system (see
 393           <command>halt</command>).</para>
 394           <indexterm zone="ch-system-systemd reboot">
 395             <primary sortas="b-reboot">reboot</primary>
 396           </indexterm>
 397         </listitem>
 398       </varlistentry>
 399
 400       <varlistentry id="runlevel">
 401         <term><command>runlevel</command></term>
 402         <listitem>
 403           <para>Reports the previous and the current run-level, as noted in the
 404           last run-level record in <filename>/var/run/utmp</filename>.</para>
 405           <indexterm zone="ch-system-systemd runlevel">
 406             <primary sortas="b-runlevel">runlevel</primary>
 407           </indexterm>
 408         </listitem>
 409       </varlistentry>
 410
 411       <varlistentry id="shutdown">
 412         <term><command>shutdown</command></term>
 413         <listitem>
 414           <para>Brings the system down in a secure way, signaling all processes
 415           and notifying all logged-in users.</para>
 416           <indexterm zone="ch-system-systemd shutdown">
 417             <primary sortas="b-shutdown">shutdown</primary>
 418           </indexterm>
 419         </listitem>
 420       </varlistentry>
 421
 422       <varlistentry id="systemctl">
 423         <term><command>systemctl</command></term>
 424         <listitem>
 425           <para>Used to introspect and control the state of the systemd system and
 426           service manager.</para>
 427           <indexterm zone="ch-system-systemd systemctl">
 428             <primary sortas="b-systemctl">systemctl</primary>
 429           </indexterm>
 430         </listitem>
 431       </varlistentry>
 432
 433       <varlistentry id="systemd-analyze">
 434         <term><command>systemd-analyze</command></term>
 435         <listitem>
 436           <para>Used to determine system boot-up performance of the current boot.
 437           </para>
 438           <indexterm zone="ch-system-systemd systemd-analyze">
 439             <primary sortas="b-systemd-analyze">systemd-analyze</primary>
 440           </indexterm>
 441         </listitem>
 442       </varlistentry>
 443
 444       <varlistentry id="systemd-ask-password">
 445         <term><command>systemd-ask-password</command></term>
 446         <listitem>
 447           <para>Used to query a system password or passphrase from the user, using a
 448           question message specified on the command line.</para>
 449           <indexterm zone="ch-system-systemd systemd-ask-password">
 450             <primary sortas="b-systemd-ask-password">systemd-ask-password</primary>
 451           </indexterm>
 452         </listitem>
 453       </varlistentry>
 454
 455       <varlistentry id="systemd-cat">
 456         <term><command>systemd-cat</command></term>
 457         <listitem>
 458           <para>Used to connect STDOUT and STDERR of a process with the Journal.
 459           </para>
 460           <indexterm zone="ch-system-systemd systemd-cat">
 461             <primary sortas="b-systemd-cat">systemd-cat</primary>
 462           </indexterm>
 463         </listitem>
 464       </varlistentry>
 465
 466       <varlistentry id="systemd-cgls">
 467         <term><command>systemd-cgls</command></term>
 468         <listitem>
 469           <para>Recursively shows the contents of the selected Linux control group
 470           hierarchy in a tree.</para>
 471           <indexterm zone="ch-system-systemd systemd-cgls">
 472             <primary sortas="b-systemd-cgls">systemd-cgls</primary>
 473           </indexterm>
 474         </listitem>
 475       </varlistentry>
 476
 477       <varlistentry id="systemd-cgtop">
 478         <term><command>systemd-cgtop</command></term>
 479         <listitem>
 480           <para>Shows the top control groups of the local Linux control group hierarchy,
 481           ordered by their CPU, memory and disk I/O load.</para>
 482           <indexterm zone="ch-system-systemd systemd-cgtop">
 483             <primary sortas="b-systemd-cgtop">systemd-cgtop</primary>
 484           </indexterm>
 485         </listitem>
 486       </varlistentry>
 487
 488       <varlistentry id="systemd-delta">
 489         <term><command>systemd-delta</command></term>
 490         <listitem>
 491           <para>Used to identify and compare configuration files in
 492           <filename class="directory">/etc</filename> that override default
 493           counterparts in <filename class="directory">/usr</filename>.</para>
 494           <indexterm zone="ch-system-systemd systemd-delta">
 495             <primary sortas="b-systemd-delta">systemd-delta</primary>
 496           </indexterm>
 497         </listitem>
 498       </varlistentry>
 499
 500       <varlistentry id="systemd-detect-virt">
 501         <term><command>systemd-detect-virt</command></term>
 502         <listitem>
 503           <para>Detects execution in a virtualized environment.</para>
 504           <indexterm zone="ch-system-systemd systemd-detect-virt">
 505             <primary sortas="b-systemd-detect-virt">systemd-detect-virt</primary>
 506           </indexterm>
 507         </listitem>
 508       </varlistentry>
 509
 510       <varlistentry id="systemd-escape">
 511         <term><command>systemd-escape</command></term>
 512         <listitem>
 513           <para>Used to escape strings for inclusion in systemd unit names.</para>
 514           <indexterm zone="ch-system-systemd systemd-escape">
 515             <primary sortas="b-systemd-escape">systemd-escape</primary>
 516           </indexterm>
 517         </listitem>
 518       </varlistentry>
 519
 520       <!-- <varlistentry id="systemd-firstboot">
 521         <term><command>systemd-firstboot</command></term>
 522         <listitem>
 523           <para>Initializes the most basic system settings interactively on the
 524           first boot.</para>
 525           <indexterm zone="ch-system-systemd systemd-firstboot">
 526             <primary sortas="b-systemd-firstboot">systemd-firstboot</primary>
 527           </indexterm>
 528         </listitem>
 529       </varlistentry> -->
 530
 531       <varlistentry id="systemd-inhibit">
 532         <term><command>systemd-inhibit</command></term>
 533         <listitem>
 534           <para>Used to execute a program with a shutdown, sleep or idle inhibitor lock
 535           taken.</para>
 536           <indexterm zone="ch-system-systemd systemd-inhibit">
 537             <primary sortas="b-systemd-inhibit">systemd-inhibit</primary>
 538           </indexterm>
 539         </listitem>
 540       </varlistentry>
 541
 542       <varlistentry id="systemd-machine-id-setup">
 543         <term><command>systemd-machine-id-setup</command></term>
 544         <listitem>
 545           <para>Used by system installer tools to initialize the machine ID stored in
 546           <filename>/etc/machine-id</filename> at install time with a randomly
 547           generated ID.</para>
 548           <indexterm zone="ch-system-systemd systemd-machine-id-setup">
 549             <primary sortas="b-systemd-machine-id-setup">systemd-machine-id-setup</primary>
 550           </indexterm>
 551         </listitem>
 552       </varlistentry>
 553
 554       <varlistentry id="systemd-notify">
 555         <term><command>systemd-notify</command></term>
 556         <listitem>
 557           <para>Used by daemon scripts to notify the init system about status changes.
 558           </para>
 559           <indexterm zone="ch-system-systemd systemd-notify">
 560             <primary sortas="b-systemd-notify">systemd-notify</primary>
 561           </indexterm>
 562         </listitem>
 563       </varlistentry>
 564
 565       <varlistentry id="systemd-nspawn">
 566         <term><command>systemd-nspawn</command></term>
 567         <listitem>
 568           <para>Used to run a command or OS in a light-weight namespace container.</para>
 569           <indexterm zone="ch-system-systemd systemd-nspawn">
 570             <primary sortas="b-systemd-nspawn">systemd-nspawn</primary>
 571           </indexterm>
 572         </listitem>
 573       </varlistentry>
 574
 575       <varlistentry id="systemd-path">
 576         <term><command>systemd-path</command></term>
 577         <listitem>
 578           <para>Used to query system and user paths.</para>
 579           <indexterm zone="ch-system-systemd systemd-path">
 580             <primary sortas="b-systemd-path">systemd-path</primary>
 581           </indexterm>
 582         </listitem>
 583       </varlistentry>
 584
 585       <varlistentry id="systemd-run">
 586         <term><command>systemd-run</command></term>
 587         <listitem>
 588           <para>Used to create and start a transient .service or a .scope unit and
 589           run the specified command in it.</para>
 590           <indexterm zone="ch-system-systemd systemd-run">
 591             <primary sortas="b-systemd-run">systemd-run</primary>
 592           </indexterm>
 593         </listitem>
 594       </varlistentry>
 595
 596       <!-- <varlistentry id="systemd-stdio-bridge">
 597         <term><command>systemd-stdio-bridge</command></term>
 598         <listitem>
 599           <para>To be completed</para>
 600           <indexterm zone="ch-system-systemd systemd-stdio-bridge">
 601             <primary sortas="b-systemd-stdio-bridge">systemd-stdio-bridge</primary>
 602           </indexterm>
 603         </listitem>
 604       </varlistentry> -->
 605
 606       <!-- <varlistentry id="systemd-sysusers">
 607         <term><command>systemd-sysusers</command></term>
 608         <listitem>
 609           <para>Creates system users and groups, based on the file format and location
 610           specified in <filename class="directory">sysusers.d</filename>.</para>
 611           <indexterm zone="ch-system-systemd systemd-sysusers">
 612             <primary sortas="b-systemd-sysusers">systemd-sysusers</primary>
 613           </indexterm>
 614         </listitem>
 615       </varlistentry> -->
 616
 617       <varlistentry id="systemd-tmpfiles">
 618         <term><command>systemd-tmpfiles</command></term>
 619         <listitem>
 620           <para>Creates, deletes and cleans up volatile and temporary files and directories,
 621           based on the configuration file format and location specified in
 622           <filename class="directory">tmpfiles.d</filename> directories.</para>
 623           <indexterm zone="ch-system-systemd systemd-tmpfiles">
 624             <primary sortas="b-systemd-tmpfiles">systemd-tmpfiles</primary>
 625           </indexterm>
 626         </listitem>
 627       </varlistentry>
 628
 629       <varlistentry id="systemd-tty-ask-password-agent">
 630         <term><command>systemd-tty-ask-password-agent</command></term>
 631         <listitem>
 632           <para>Used to list or process pending systemd password requests</para>
 633           <indexterm zone="ch-system-systemd systemd-tty-ask-password-agent">
 634             <primary sortas="b-systemd-tty-ask-password-agent">systemd-tty-ask-password-agent</primary>
 635           </indexterm>
 636         </listitem>
 637       </varlistentry>
 638
 639       <varlistentry id="telinit">
 640         <term><command>telinit</command></term>
 641         <listitem>
 642           <para>Tells <command>init</command> which run-level to change to.</para>
 643           <indexterm zone="ch-system-systemd telinit">
 644             <primary sortas="b-telinit">telinit</primary>
 645           </indexterm>
 646         </listitem>
 647       </varlistentry>
 648
 649       <varlistentry id="timedatectl">
 650         <term><command>timedatectl</command></term>
 651         <listitem>
 652           <para>Used to query and change the system clock and its settings.
 653           </para>
 654           <indexterm zone="ch-system-systemd timedatectl">
 655             <primary sortas="b-timedatectl">timedatectl</primary>
 656           </indexterm>
 657         </listitem>
 658       </varlistentry>
 659
 660       <varlistentry id="udevadm">
 661         <term><command>udevadm</command></term>
 662         <listitem>
 663           <para>Generic Udev administration tool: controls the udevd daemon,
 664           provides info from the Udev database, monitors uevents, waits for
 665           uevents to finish, tests Udev configuration, and triggers uevents
 666           for a given device.</para>
 667           <indexterm zone="ch-system-systemd udevadm">
 668             <primary sortas="b-udevadm">udevadm</primary>
 669           </indexterm>
 670         </listitem>
 671       </varlistentry>
 672
 673       <varlistentry id="libsystemd">
 674         <term><filename class="libraryfile">libsystemd</filename></term>
 675         <listitem>
 676           <para>systemd utility library.</para>
 677           <indexterm zone="ch-system-systemd libsystemd">
 678             <primary sortas="c-libsystemd">libsystemd</primary>
 679           </indexterm>
 680         </listitem>
 681       </varlistentry>
 682
 683       <varlistentry id="libudev">
 684         <term><filename class="libraryfile">libudev</filename></term>
 685         <listitem>
 686           <para>A library to access Udev device information.</para>
 687           <indexterm zone="ch-system-systemd libudev">
 688             <primary sortas="c-libudev">libudev</primary>
 689           </indexterm>
 690         </listitem>
 691       </varlistentry>
 692
 693     </variablelist>
 694
 695   </sect2>
 696
 697 </sect1>