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