systemd.xml 24 KB

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