BOOK/chapter06/systemd.xml

   1 <?xml version="1.0" encoding="ISO-8859-1"?>
   2 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
   4   <!ENTITY % general-entities SYSTEM "../general.ent">
   5   %general-entities;
   6 ]>
   7
   8 <sect1 id="ch-system-systemd" role="wrap" revision="systemd">
   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, fix a build error when using Util-Linux built in
  44     Chapter 5:</para>
  45
  46 <screen><userinput remap="pre">sed -i "s:blkid/::" $(grep -rl "blkid/blkid.h")</userinput></screen>
  47
  48 <!-- Not needed as of 231. -renodr
  49     <para>Fix a potential security issue with framebuffer devices:</para>
  50
  51 <screen><userinput remap="pre">sed -e 's@DRI and frame buffer@DRI@'                  \
  52     -e '/SUBSYSTEM==\"graphics\", KERNEL==\"fb\*\"/d' \
  53     -i  src/login/70-uaccess.rules</userinput></screen>
  54 -->
  55
  56     <para>Disable two tests that always fail:</para>
  57
  58 <screen><userinput remap="pre">sed -e 's@test/udev-test.pl @@'  \
  59     -e 's@test-copy$(EXEEXT) @@' \
  60     -i Makefile.in</userinput></screen>
  61
  62     <para>Rebuild generated files after modifying Makefile.am and
  63     Makefile.in:</para>
  64
  65 <screen><userinput remap="pre">autoreconf -fi</userinput></screen>
  66
  67     <para>Create a file to allow systemd to build when using Util-Linux
  68     built in Chapter 5, to disable LTO by default, and to build without
  69     xlstproc:</para>
  70
  71 <screen><userinput remap="pre">cat &gt; config.cache &lt;&lt; "EOF"
  72 <literal>KILL=/bin/kill
  73 MOUNT_PATH=/bin/mount
  74 UMOUNT_PATH=/bin/umount
  75 HAVE_BLKID=1
  76 BLKID_LIBS="-lblkid"
  77 BLKID_CFLAGS="-I/tools/include/blkid"
  78 HAVE_LIBMOUNT=1
  79 MOUNT_LIBS="-lmount"
  80 MOUNT_CFLAGS="-I/tools/include/libmount"
  81 cc_cv_CFLAGS__flto=no
  82 XSLTPROC="/usr/bin/xsltproc"</literal>
  83 EOF</userinput></screen>
  84
  85     <para>LTO is disabled by default because it causes
  86     <command>systemd</command> and other auxiliary programs to link to
  87     <filename class="libraryfile">libgcc_s.so</filename>, slows the build down
  88     and makes the compiled code larger.</para>
  89
  90     <para>Prepare systemd for compilation:</para>
  91
  92 <screen><userinput remap="configure">./configure --prefix=/usr            \
  93             --sysconfdir=/etc        \
  94             --localstatedir=/var     \
  95             --config-cache           \
  96             --with-rootprefix=       \
  97             --with-rootlibdir=/lib   \
  98             --enable-split-usr       \
  99             --disable-firstboot      \
 100             --disable-ldconfig       \
 101             --disable-sysusers       \
 102             --without-python         \
 103             --with-default-dnssec=no \
 104             --docdir=/usr/share/doc/systemd-&systemd-version;</userinput></screen>
 105
 106     <variablelist>
 107       <title>The meaning of the configure options:</title>
 108
 109       <varlistentry>
 110         <term><parameter>--config-cache</parameter></term>
 111         <listitem>
 112           <para>This switch tells the build system to use
 113           the <filename>config.cache</filename> file which
 114           was created earlier.</para>
 115         </listitem>
 116       </varlistentry>
 117
 118       <varlistentry>
 119         <term><parameter>--with-root*</parameter></term>
 120         <listitem>
 121           <para>These switches ensure that core programs and
 122           shared libraries are installed in the subdirectories
 123           of the root partition.</para>
 124         </listitem>
 125       </varlistentry>
 126
 127       <varlistentry>
 128         <term><parameter>--enable-split-usr</parameter></term>
 129         <listitem>
 130           <para>This switch ensures that systemd will work on
 131           systems where /bin, /lib and /sbin directories are not
 132           symlinks to their /usr counterparts.</para>
 133         </listitem>
 134       </varlistentry>
 135
 136       <varlistentry>
 137         <term><parameter>--without-python</parameter></term>
 138         <listitem>
 139           <para>This switch prevents <command>configure</command>
 140           from trying to use Python which isn't built
 141           in LFS.</para>
 142         </listitem>
 143       </varlistentry>
 144
 145       <varlistentry>
 146         <term><parameter>--disable-firstboot</parameter></term>
 147         <listitem>
 148           <para>This switch prevents installation of systemd
 149           services responsible for setting up the system for
 150           the first time. They are not useful for LFS because
 151           everything is done manually.</para>
 152         </listitem>
 153       </varlistentry>
 154
 155       <varlistentry>
 156         <term><parameter>--disable-ldconfig</parameter></term>
 157         <listitem>
 158           <para>This switch prevents installation of a systemd
 159           unit that runs <command>ldconfig</command> at
 160           boot, making the boot time longer. Remove it if the
 161           described feature is desired, even though it's not
 162           useful for source distributions such as LFS.</para>
 163         </listitem>
 164       </varlistentry>
 165
 166       <varlistentry>
 167         <term><parameter>--disable-sysusers</parameter></term>
 168         <listitem>
 169           <para>This switch prevents installation of systemd
 170           services responsible for setting up the
 171           <filename>/etc/group</filename> and
 172           <filename>/etc/passwd</filename> files. Both files
 173           were created early in this chapter.</para>
 174         </listitem>
 175       </varlistentry>
 176
 177       <varlistentry>
 178         <term><parameter>--with-default-dnssec=no</parameter></term>
 179         <listitem>
 180           <para>This switch turns off the experimental DNSSEC suport.</para>
 181         </listitem>
 182       </varlistentry>
 183
 184     </variablelist>
 185
 186     <para>Compile the package:</para>
 187
 188 <screen><userinput remap="make">make LIBRARY_PATH=/tools/lib</userinput></screen>
 189
 190     <para>This package has a test suite, but it can only be run after the
 191     package has been installed.</para>
 192
 193     <para>Install the package:</para>
 194
 195 <screen><userinput remap="install">make LD_LIBRARY_PATH=/tools/lib install</userinput></screen>
 196
 197     <para>Move the NSS libraries to <filename class="directory">/lib</filename>:</para>
 198
 199 <screen><userinput remap="install">mv -v /usr/lib/libnss_{myhostname,mymachines,resolve}.so.2 /lib</userinput></screen>
 200
 201     <para>Remove an unnecessary directory:</para>
 202
 203 <screen><userinput remap="install">rm -rfv /usr/lib/rpm</userinput></screen>
 204
 205     <para>Create the Sysvinit compatibility symlinks, so systemd is used
 206     as the default init system:</para>
 207
 208 <screen><userinput remap="install">for tool in runlevel reboot shutdown poweroff halt telinit; do
 209      ln -sfv ../bin/systemctl /sbin/${tool}
 210 done
 211 ln -sfv ../lib/systemd/systemd /sbin/init</userinput></screen>
 212
 213 <!--
 214     <para>Remove a reference to a non-existent group:</para>
 215
 216 <screen><userinput remap="install">sed -i "s:0775 root lock:0755 root root:g" /usr/lib/tmpfiles.d/legacy.conf</userinput></screen>
 217 -->
 218
 219     <para>Create the <filename>/etc/machine-id</filename> file needed by
 220     <command>systemd-journald</command>:</para>
 221
 222 <screen><userinput remap="install">systemd-machine-id-setup</userinput></screen>
 223
 224     <para>Fix a broken symlink created by the systemd installation process:</para>
 225 <screen><userinput remap="install">rm -v /etc/resolv.conf
 226 ln -s ../lib/systemd/resolv.conf /etc/resolv.conf</userinput></screen>
 227
 228     <para>Since the testsuite largely depends on the host system kernel
 229     configuration, some tests may fail. It also needs a modification in
 230     order not to look for a program that will be installed by Util-Linux
 231     package later in this chapter. To test the results, issue:</para>
 232
 233 <screen><userinput remap="test">sed -i "s:minix:ext4:g" src/test/test-path-util.c
 234 make LD_LIBRARY_PATH=/tools/lib -k check</userinput></screen>
 235
 236   </sect2>
 237
 238   <sect2 id="contents-systemd" role="content">
 239     <title>Contents of systemd</title>
 240
 241     <segmentedlist>
 242       <segtitle>Installed programs</segtitle>
 243       <segtitle>Installed libraries</segtitle>
 244       <segtitle>Installed directories</segtitle>
 245
 246       <seglistitem>
 247         <seg>bootctl, busctl, coredumpctl, halt, hostnamectl, init, journalctl,
 248         kernel-install, localectl, loginctl, machinectl, networkctl, poweroff,
 249         reboot, runlevel, shutdown, systemctl, systemd-analyze,
 250         systemd-ask-password, systemd-cat, systemd-cgls, systemd-cgtop,
 251         systemd-delta, systemd-detect-virt, systemd-escape, systemd-hwdb,
 252         systemd-inhibit, systemd-machine-id-setup, systemd-notify,
 253         systemd-nspawn, systemd-path, systemd-resolve, systemd-run,
 254         systemd-stdio-bridge, systemd-tmpfiles, systemd-tty-ask-password-agent,
 255         telinit, timedatectl, and udevadm</seg>
 256         <seg>libnss_myhostname.so.2, libnss_mymachines.so.2,
 257         libnss_resolve.so.2, libsystemd.so, libsystemd-shared-231.so,
 258         and libudev.so</seg>
 259         <seg>/etc/binfmt.d, /etc/init.d, /etc/kernel, /etc/modules-load.d,
 260         /etc/sysctl.d, /etc/systemd, /etc/tmpfiles.d, /etc/udev,
 261         /etc/xdg/systemd, /lib/systemd, /lib/udev, /usr/include/systemd,
 262         /usr/lib/binfmt.d, /usr/lib/kernel, /usr/lib/modules-load.d,
 263         /usr/lib/sysctl.d, /usr/lib/systemd, /usr/lib/tmpfiles.d,
 264         /usr/share/doc/systemd-&systemd-version;, /usr/share/factory,
 265         /usr/share/systemd, /var/lib/systemd, and /var/log/journal</seg>
 266       </seglistitem>
 267     </segmentedlist>
 268
 269     <variablelist>
 270       <bridgehead renderas="sect3">Short Descriptions</bridgehead>
 271       <?dbfo list-presentation="list"?>
 272       <?dbhtml list-presentation="table"?>
 273
 274       <varlistentry id="bootctl">
 275         <term><command>bootctl</command></term>
 276         <listitem>
 277           <para>used to query the firmware and boot manager settings</para>
 278           <indexterm zone="ch-system-systemd bootctl">
 279             <primary sortas="b-bootctl">bootctl</primary>
 280           </indexterm>
 281         </listitem>
 282       </varlistentry>
 283
 284       <varlistentry id="busctl">
 285         <term><command>busctl</command></term>
 286         <listitem>
 287           <para>Used to introspect and monitor the D-Bus bus</para>
 288           <indexterm zone="ch-system-systemd busctl">
 289             <primary sortas="b-busctl">busctl</primary>
 290           </indexterm>
 291         </listitem>
 292       </varlistentry>
 293
 294       <varlistentry id="coredumpctl">
 295         <term><command>coredumpctl</command></term>
 296         <listitem>
 297           <para>Used to retrieve coredumps from the systemd Journal</para>
 298           <indexterm zone="ch-system-systemd coredumpctl">
 299             <primary sortas="b-coredumpctl">coredumpctl</primary>
 300           </indexterm>
 301         </listitem>
 302       </varlistentry>
 303
 304       <varlistentry id="halt">
 305         <term><command>halt</command></term>
 306         <listitem>
 307           <para>Normally invokes <command>shutdown</command> with the
 308           <parameter>-h</parameter> option, except when already in run-level 0,
 309           then it tells the kernel to halt the system; it notes in the
 310           file <filename>/var/log/wtmp</filename> that the system is being
 311           brought down</para>
 312           <indexterm zone="ch-system-systemd halt">
 313             <primary sortas="b-halt">halt</primary>
 314           </indexterm>
 315         </listitem>
 316       </varlistentry>
 317
 318       <varlistentry id="hostnamectl">
 319         <term><command>hostnamectl</command></term>
 320         <listitem>
 321           <para>Used to query and change the system hostname and related
 322           settings</para>
 323           <indexterm zone="ch-system-systemd hostnamectl">
 324             <primary sortas="b-hostnamectl">hostnamectl</primary>
 325           </indexterm>
 326         </listitem>
 327       </varlistentry>
 328
 329       <varlistentry id="init">
 330         <term><command>init</command></term>
 331         <listitem>
 332           <para>The first process to be started when the kernel has initialized
 333           the hardware which takes over the boot process and starts all the
 334           proceses it is instructed to</para>
 335           <indexterm zone="ch-system-systemd init">
 336             <primary sortas="b-init">init</primary>
 337           </indexterm>
 338         </listitem>
 339       </varlistentry>
 340
 341       <varlistentry id="journalctl">
 342         <term><command>journalctl</command></term>
 343         <listitem>
 344           <para>Used to query the contents of the systemd Journal</para>
 345           <indexterm zone="ch-system-systemd journalctl">
 346             <primary sortas="b-journalctl">journalctl</primary>
 347           </indexterm>
 348         </listitem>
 349       </varlistentry>
 350
 351       <varlistentry id="kernel-install">
 352         <term><command>kernel-install</command></term>
 353         <listitem>
 354           <para>Used to add and remove kernel and initramfs images to and
 355           from /boot</para>
 356           <indexterm zone="ch-system-systemd kernel-install">
 357             <primary sortas="b-kernel-install">kernel-install</primary>
 358           </indexterm>
 359         </listitem>
 360       </varlistentry>
 361
 362       <varlistentry id="localectl">
 363         <term><command>localectl</command></term>
 364         <listitem>
 365           <para>Used to query and change the system locale and keyboard layout
 366           settings</para>
 367           <indexterm zone="ch-system-systemd localectl">
 368             <primary sortas="b-localectl">localectl</primary>
 369           </indexterm>
 370         </listitem>
 371       </varlistentry>
 372
 373       <varlistentry id="loginctl">
 374         <term><command>loginctl</command></term>
 375         <listitem>
 376           <para>Used to introspect and control the state of the systemd Login
 377           Manager</para>
 378           <indexterm zone="ch-system-systemd loginctl">
 379             <primary sortas="b-loginctl">loginctl</primary>
 380           </indexterm>
 381         </listitem>
 382       </varlistentry>
 383
 384       <varlistentry id="machinectl">
 385         <term><command>machinectl</command></term>
 386         <listitem>
 387           <para>Used to introspect and control the state of the systemd Virtual
 388           Machine and Container Registration Manager</para>
 389           <indexterm zone="ch-system-systemd machinectl">
 390             <primary sortas="b-machinectl">machinectl</primary>
 391           </indexterm>
 392         </listitem>
 393       </varlistentry>
 394
 395       <varlistentry id="networkctl">
 396         <term><command>networkctl</command></term>
 397         <listitem>
 398           <para>Used to introspect the state of the network links as seen by
 399           systemd-networkd</para>
 400           <indexterm zone="ch-system-systemd networkctl">
 401             <primary sortas="b-networkctl">networkctl</primary>
 402           </indexterm>
 403         </listitem>
 404       </varlistentry>
 405
 406       <varlistentry id="poweroff">
 407         <term><command>poweroff</command></term>
 408         <listitem>
 409           <para>Tells the kernel to halt the system and switch off the computer
 410           (see <command>halt</command>)</para>
 411           <indexterm zone="ch-system-systemd poweroff">
 412             <primary sortas="b-poweroff">poweroff</primary>
 413           </indexterm>
 414         </listitem>
 415       </varlistentry>
 416
 417       <varlistentry id="reboot">
 418         <term><command>reboot</command></term>
 419         <listitem>
 420           <para>Tells the kernel to reboot the system (see
 421           <command>halt</command>)</para>
 422           <indexterm zone="ch-system-systemd reboot">
 423             <primary sortas="b-reboot">reboot</primary>
 424           </indexterm>
 425         </listitem>
 426       </varlistentry>
 427
 428       <varlistentry id="runlevel">
 429         <term><command>runlevel</command></term>
 430         <listitem>
 431           <para>Reports the previous and the current run-level, as noted in the
 432           last run-level record in <filename>/var/run/utmp</filename></para>
 433           <indexterm zone="ch-system-systemd runlevel">
 434             <primary sortas="b-runlevel">runlevel</primary>
 435           </indexterm>
 436         </listitem>
 437       </varlistentry>
 438
 439       <varlistentry id="shutdown">
 440         <term><command>shutdown</command></term>
 441         <listitem>
 442           <para>Brings the system down in a secure way, signaling all processes
 443           and notifying all logged-in users</para>
 444           <indexterm zone="ch-system-systemd shutdown">
 445             <primary sortas="b-shutdown">shutdown</primary>
 446           </indexterm>
 447         </listitem>
 448       </varlistentry>
 449
 450       <varlistentry id="systemctl">
 451         <term><command>systemctl</command></term>
 452         <listitem>
 453           <para>Used to introspect and control the state of the systemd system
 454           and service manager</para>
 455           <indexterm zone="ch-system-systemd systemctl">
 456             <primary sortas="b-systemctl">systemctl</primary>
 457           </indexterm>
 458         </listitem>
 459       </varlistentry>
 460
 461       <varlistentry id="systemd-analyze">
 462         <term><command>systemd-analyze</command></term>
 463         <listitem>
 464           <para>Used to determine system boot-up performance of the current
 465           boot</para>
 466           <indexterm zone="ch-system-systemd systemd-analyze">
 467             <primary sortas="b-systemd-analyze">systemd-analyze</primary>
 468           </indexterm>
 469         </listitem>
 470       </varlistentry>
 471
 472       <varlistentry id="systemd-ask-password">
 473         <term><command>systemd-ask-password</command></term>
 474         <listitem>
 475           <para>Used to query a system password or passphrase from the user,
 476           using a question message specified on the command line</para>
 477           <indexterm zone="ch-system-systemd systemd-ask-password">
 478             <primary sortas="b-systemd-ask-password">systemd-ask-password</primary>
 479           </indexterm>
 480         </listitem>
 481       </varlistentry>
 482
 483       <varlistentry id="systemd-cat">
 484         <term><command>systemd-cat</command></term>
 485         <listitem>
 486           <para>Used to connect STDOUT and STDERR of a process with the Journal
 487           </para>
 488           <indexterm zone="ch-system-systemd systemd-cat">
 489             <primary sortas="b-systemd-cat">systemd-cat</primary>
 490           </indexterm>
 491         </listitem>
 492       </varlistentry>
 493
 494       <varlistentry id="systemd-cgls">
 495         <term><command>systemd-cgls</command></term>
 496         <listitem>
 497           <para>Recursively shows the contents of the selected Linux control
 498           group hierarchy in a tree</para>
 499           <indexterm zone="ch-system-systemd systemd-cgls">
 500             <primary sortas="b-systemd-cgls">systemd-cgls</primary>
 501           </indexterm>
 502         </listitem>
 503       </varlistentry>
 504
 505       <varlistentry id="systemd-cgtop">
 506         <term><command>systemd-cgtop</command></term>
 507         <listitem>
 508           <para>Shows the top control groups of the local Linux control group
 509           hierarchy, ordered by their CPU, memory and disk I/O load</para>
 510           <indexterm zone="ch-system-systemd systemd-cgtop">
 511             <primary sortas="b-systemd-cgtop">systemd-cgtop</primary>
 512           </indexterm>
 513         </listitem>
 514       </varlistentry>
 515
 516       <varlistentry id="systemd-delta">
 517         <term><command>systemd-delta</command></term>
 518         <listitem>
 519           <para>Used to identify and compare configuration files in
 520           <filename class="directory">/etc</filename> that override default
 521           counterparts in <filename class="directory">/usr</filename></para>
 522           <indexterm zone="ch-system-systemd systemd-delta">
 523             <primary sortas="b-systemd-delta">systemd-delta</primary>
 524           </indexterm>
 525         </listitem>
 526       </varlistentry>
 527
 528       <varlistentry id="systemd-detect-virt">
 529         <term><command>systemd-detect-virt</command></term>
 530         <listitem>
 531           <para>Detects execution in a virtualized environment</para>
 532           <indexterm zone="ch-system-systemd systemd-detect-virt">
 533             <primary sortas="b-systemd-detect-virt">systemd-detect-virt</primary>
 534           </indexterm>
 535         </listitem>
 536       </varlistentry>
 537
 538       <varlistentry id="systemd-escape">
 539         <term><command>systemd-escape</command></term>
 540         <listitem>
 541           <para>Used to escape strings for inclusion in systemd unit
 542           names</para>
 543           <indexterm zone="ch-system-systemd systemd-escape">
 544             <primary sortas="b-systemd-escape">systemd-escape</primary>
 545           </indexterm>
 546         </listitem>
 547       </varlistentry>
 548
 549       <varlistentry id="systemd-hwdb">
 550         <term><command>systemd-hwdb</command></term>
 551         <listitem>
 552           <para>Used to manage hardware database (hwdb)</para>
 553           <indexterm zone="ch-system-systemd systemd-hwdb">
 554             <primary sortas="b-systemd-hwdb">systemd-hwdb</primary>
 555           </indexterm>
 556         </listitem>
 557       </varlistentry>
 558
 559       <varlistentry id="systemd-inhibit">
 560         <term><command>systemd-inhibit</command></term>
 561         <listitem>
 562           <para>Used to execute a program with a shutdown, sleep or idle
 563           inhibitor lock taken</para>
 564           <indexterm zone="ch-system-systemd systemd-inhibit">
 565             <primary sortas="b-systemd-inhibit">systemd-inhibit</primary>
 566           </indexterm>
 567         </listitem>
 568       </varlistentry>
 569
 570       <varlistentry id="systemd-machine-id-setup">
 571         <term><command>systemd-machine-id-setup</command></term>
 572         <listitem>
 573           <para>Used by system installer tools to initialize the machine ID
 574           stored in <filename>/etc/machine-id</filename> at install time with a
 575           randomly generated ID</para>
 576           <indexterm zone="ch-system-systemd systemd-machine-id-setup">
 577             <primary sortas="b-systemd-machine-id-setup">systemd-machine-id-setup</primary>
 578           </indexterm>
 579         </listitem>
 580       </varlistentry>
 581
 582       <varlistentry id="systemd-notify">
 583         <term><command>systemd-notify</command></term>
 584         <listitem>
 585           <para>Used by daemon scripts to notify the init system about status
 586           changes</para>
 587           <indexterm zone="ch-system-systemd systemd-notify">
 588             <primary sortas="b-systemd-notify">systemd-notify</primary>
 589           </indexterm>
 590         </listitem>
 591       </varlistentry>
 592
 593       <varlistentry id="systemd-nspawn">
 594         <term><command>systemd-nspawn</command></term>
 595         <listitem>
 596           <para>Used to run a command or OS in a light-weight namespace
 597           container</para>
 598           <indexterm zone="ch-system-systemd systemd-nspawn">
 599             <primary sortas="b-systemd-nspawn">systemd-nspawn</primary>
 600           </indexterm>
 601         </listitem>
 602       </varlistentry>
 603
 604       <varlistentry id="systemd-path">
 605         <term><command>systemd-path</command></term>
 606         <listitem>
 607           <para>Used to query system and user paths</para>
 608           <indexterm zone="ch-system-systemd systemd-path">
 609             <primary sortas="b-systemd-path">systemd-path</primary>
 610           </indexterm>
 611         </listitem>
 612       </varlistentry>
 613
 614       <varlistentry id="systemd-resolve">
 615         <term><command>systemd-resolve</command></term>
 616         <listitem>
 617           <para>Used to resolve domain names, IPV4 and IPv6 addresses, DNS
 618           resource records, and services</para>
 619           <indexterm zone="ch-system-systemd systemd-resolve">
 620             <primary sortas="b-systemd-resolve">systemd-resolve</primary>
 621           </indexterm>
 622         </listitem>
 623       </varlistentry>
 624
 625       <varlistentry id="systemd-run">
 626         <term><command>systemd-run</command></term>
 627         <listitem>
 628           <para>Used to create and start a transient .service or a .scope unit
 629           and run the specified command in it</para>
 630           <indexterm zone="ch-system-systemd systemd-run">
 631             <primary sortas="b-systemd-run">systemd-run</primary>
 632           </indexterm>
 633         </listitem>
 634       </varlistentry>
 635
 636       <!-- <varlistentry id="systemd-stdio-bridge">
 637         <term><command>systemd-stdio-bridge</command></term>
 638         <listitem>
 639           <para>To be completed</para>
 640           <indexterm zone="ch-system-systemd systemd-stdio-bridge">
 641             <primary sortas="b-systemd-stdio-bridge">systemd-stdio-bridge</primary>
 642           </indexterm>
 643         </listitem>
 644       </varlistentry> -->
 645
 646       <varlistentry id="systemd-tmpfiles">
 647         <term><command>systemd-tmpfiles</command></term>
 648         <listitem>
 649           <para>Creates, deletes and cleans up volatile and temporary files and
 650           directories, based on the configuration file format and location
 651           specified in
 652           <filename class="directory">tmpfiles.d</filename> directories</para>
 653           <indexterm zone="ch-system-systemd systemd-tmpfiles">
 654             <primary sortas="b-systemd-tmpfiles">systemd-tmpfiles</primary>
 655           </indexterm>
 656         </listitem>
 657       </varlistentry>
 658
 659       <varlistentry id="systemd-tty-ask-password-agent">
 660         <term><command>systemd-tty-ask-password-agent</command></term>
 661         <listitem>
 662           <para>Used to list or process pending systemd password requests</para>
 663           <indexterm zone="ch-system-systemd systemd-tty-ask-password-agent">
 664             <primary sortas="b-systemd-tty-ask-password-agent">systemd-tty-ask-password-agent</primary>
 665           </indexterm>
 666         </listitem>
 667       </varlistentry>
 668
 669       <varlistentry id="telinit">
 670         <term><command>telinit</command></term>
 671         <listitem>
 672           <para>Tells <command>init</command> which run-level to change
 673           to</para>
 674           <indexterm zone="ch-system-systemd telinit">
 675             <primary sortas="b-telinit">telinit</primary>
 676           </indexterm>
 677         </listitem>
 678       </varlistentry>
 679
 680       <varlistentry id="timedatectl">
 681         <term><command>timedatectl</command></term>
 682         <listitem>
 683           <para>Used to query and change the system clock and its settings
 684           </para>
 685           <indexterm zone="ch-system-systemd timedatectl">
 686             <primary sortas="b-timedatectl">timedatectl</primary>
 687           </indexterm>
 688         </listitem>
 689       </varlistentry>
 690
 691       <varlistentry id="udevadm">
 692         <term><command>udevadm</command></term>
 693         <listitem>
 694           <para>Generic Udev administration tool: controls the udevd daemon,
 695           provides info from the Udev database, monitors uevents, waits for
 696           uevents to finish, tests Udev configuration, and triggers uevents
 697           for a given device</para>
 698           <indexterm zone="ch-system-systemd udevadm">
 699             <primary sortas="b-udevadm">udevadm</primary>
 700           </indexterm>
 701         </listitem>
 702       </varlistentry>
 703
 704       <varlistentry id="libsystemd">
 705         <term><filename class="libraryfile">libsystemd</filename></term>
 706         <listitem>
 707           <para>systemd utility library</para>
 708           <indexterm zone="ch-system-systemd libsystemd">
 709             <primary sortas="c-libsystemd">libsystemd</primary>
 710           </indexterm>
 711         </listitem>
 712       </varlistentry>
 713
 714       <varlistentry id="libudev">
 715         <term><filename class="libraryfile">libudev</filename></term>
 716         <listitem>
 717           <para>A library to access Udev device information</para>
 718           <indexterm zone="ch-system-systemd libudev">
 719             <primary sortas="c-libudev">libudev</primary>
 720           </indexterm>
 721         </listitem>
 722       </varlistentry>
 723
 724     </variablelist>
 725
 726   </sect2>
 727
 728 </sect1>