<refmeta>
<refentrytitle>systemd</refentrytitle>
- <manvolnum>8</manvolnum>
+ <manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd</refname>
+ <refname>init</refname>
<refpurpose>systemd System and Session Manager</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
- <command>systemd <arg choice="opt" rep="repeat">options</arg></command>
+ <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command>
</cmdsynopsis>
<cmdsynopsis>
- <command>init <arg choice="opt" rep="repeat">options</arg></command>
+ <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
</cmdsynopsis>
</refsynopsisdiv>
<para>systemd is a system and session manager for
Linux operating systems. When run as first process on
- boot (as PID 1) it may act as init system that brings
- up and maintains userspace.</para>
+ boot (as PID 1), it acts as init system that brings
+ up and maintains userspace services.</para>
- <para>For compatibility with SysV if systemd is called
+ <para>For compatibility with SysV, if systemd is called
as <command>init</command> and a PID that is not
- 1 it will execute <command>telinit</command> and pass
+ 1, it will execute <command>telinit</command> and pass
all command line arguments unmodified. That means
<command>init</command> and <command>telinit</command>
are mostly equivalent when invoked from normal login sessions. See
<variablelist>
<varlistentry>
- <term><option>-h</option> | <option>--help</option></term>
+ <term><option>-h</option></term>
+ <term><option>--help</option></term>
<listitem><para>Prints a short help
text and exits.</para></listitem>
<listitem><para>Dump understood unit
configuration items. This outputs a
- terse list of configuration items
- understood in unit definition
- files.</para></listitem>
+ terse but complete list of
+ configuration items understood in unit
+ definition files.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--confirm-spawn</option></term>
<listitem><para>Extract D-Bus
interface introspection data. This is
- mostly useful at build ot install time
+ mostly useful at build at install time
to generate data suitable for the
D-Bus interfaces
repository. Optionally the interface
name for the introspection data may be
- specified. If omitted the
+ specified. If omitted, the
introspection data for all interfaces
is dumped.</para></listitem>
</varlistentry>
it defaults to
<option>true</option>.</para></listitem>
</varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Directories</title>
+
+ <variablelist>
+ <varlistentry>
+ <term>System unit directories</term>
+
+ <listitem><para>The systemd system
+ manager reads unit configuration from
+ various directories. Packages that
+ want to install unit files shall place
+ them in the directory returned by
+ <command>pkg-config systemd
+ --variable=systemdsystemunitdir</command>. Other
+ directories checked are
+ <filename>/usr/local/share/systemd/system</filename>
+ and
+ <filename>/usr/share/systemd/system</filename>. User
+ configuration always takes
+ precedence. <command>pkg-config
+ systemd
+ --variable=systemdsystemconfdir</command>
+ returns the path of the system
+ configuration directory. Packages
+ should alter the content of these directories
+ only with the
+ <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ tool.</para></listitem>
+ </varlistentry>
+ </variablelist>
+
+ <variablelist>
+ <varlistentry>
+ <term>Session unit directories</term>
+
+ <listitem><para>Similar rules apply
+ for the session unit
+ directories. However, here the <ulink
+ url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
+ Base Directory specification</ulink>
+ is followed to find
+ units. Applications should place their
+ unit files in the directory returned
+ by <command>pkg-config systemd
+ --variable=systemdsessionunitdir</command>. Global
+ configuration is done in the
+ directory reported by
+ <command>pkg-config systemd
+ --variable=systemdsessionconfdir</command>. The
+ <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ tool can handle both global (i.e. for
+ all users) and private (for one user)
+ enabling/disabling of
+ units.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ <variablelist>
+ <varlistentry>
+ <term>SysV init scripts directory</term>
+
+ <listitem><para>The location of the
+ SysV init script directory varies
+ between distributions. If systemd
+ cannot find a native unit file for a
+ requested service, it will look for a
+ SysV init script of the same name
+ (with the
+ <filename>.service</filename> suffix
+ removed).</para></listitem>
+ </varlistentry>
+ </variablelist>
+ <variablelist>
+ <varlistentry>
+ <term>SysV runlevel link farm directory</term>
+
+ <listitem><para>The location of the
+ SysV runlevel link farm directory
+ varies between distributions. systemd
+ will take the link farm into account
+ when figuring out whether a service
+ shall be enabled. Note that a service
+ unit with a native unit configuration
+ file can be started by activating it
+ in the SysV runlevel link
+ farm.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Signals</title>
+
+ <variablelist>
+ <varlistentry>
+ <term>SIGTERM</term>
+
+ <listitem><para>Upon receiving this
+ signal the systemd system manager
+ serializes its state, reexecutes
+ itself and deserializes the saved
+ state again. This is mostly equivalent
+ to <command>systemctl
+ daemon-reexec</command>.</para>
+
+ <para>systemd session managers will
+ start the
+ <filename>exit.target</filename> unit
+ when this signal is received. This is
+ mostly equivalent to
+ <command>systemctl --session start
+ exit.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGINT</term>
+
+ <listitem><para>Upon receiving this
+ signal the systemd system manager will
+ start the
+ <filename>ctrl-alt-del.target</filename> unit. This
+ is mostly equivalent to
+ <command>systemctl start
+ ctl-alt-del.target</command>.</para>
+
+ <para>systemd session managers
+ treat this signal the same way as
+ SIGTERM.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGWINCH</term>
+
+ <listitem><para>When this signal is
+ received the systemd system manager
+ will start the
+ <filename>kbrequest.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ kbrequest.target</command>.</para>
+
+ <para>This signal is ignored by
+ systemd session
+ managers.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGPWR</term>
+
+ <listitem><para>When this signal is
+ received the systemd manager
+ will start the
+ <filename>sigpwr.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ sigpwr.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGUSR1</term>
+
+ <listitem><para>When this signal is
+ received the systemd manager will try
+ to reconnect to the D-Bus
+ bus.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGUSR2</term>
+
+ <listitem><para>When this signal is
+ received the systemd manager will log
+ its complete state in human readable
+ form. The data logged is the same as
+ printed by <command>systemctl
+ dump</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGHUP</term>
+
+ <listitem><para>Reloads the complete
+ daemon configuration. This is mostly
+ equivalent to <command>systemctl
+ daemon-reload</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+0</term>
+
+ <listitem><para>Enters default mode, starts the
+ <filename>default.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ default.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+1</term>
+
+ <listitem><para>Enters rescue mode,
+ starts the
+ <filename>rescue.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl isolate
+ rescue.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+2</term>
+
+ <listitem><para>Enters emergency mode,
+ starts the
+ <filename>emergency.service</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl isolate
+ emergency.service</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+3</term>
+
+ <listitem><para>Halts the machine,
+ starts the
+ <filename>halt.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ halt.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+4</term>
+
+ <listitem><para>Powers off the machine,
+ starts the
+ <filename>poweroff.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ poweroff.target</command>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>SIGRTMIN+5</term>
+
+ <listitem><para>Reboots the machine,
+ starts the
+ <filename>reboot.target</filename>
+ unit. This is mostly equivalent to
+ <command>systemctl start
+ reboot.target</command>.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Environment</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><varname>$SYSTEMD_LOG_LEVEL</varname></term>
+ <listitem><para>systemd reads the
+ log level from this environment
+ variable. This can be overridden with
+ <option>--log-level=</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_LOG_TARGET</varname></term>
+ <listitem><para>systemd reads the
+ log target from this environment
+ variable. This can be overridden with
+ <option>--log-target=</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_LOG_COLOR</varname></term>
+ <listitem><para>Controls whether
+ systemd highlights important log
+ messages. This can be overridden with
+ <option>--log-color=</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_LOG_LOCATION</varname></term>
+ <listitem><para>Controls whether
+ systemd prints the code location along
+ with log messages. This can be
+ overridden with
+ <option>--log-location=</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$XDG_CONFIG_HOME</varname></term>
+ <term><varname>$XDG_CONFIG_DIRS</varname></term>
+ <term><varname>$XDG_DATA_HOME</varname></term>
+ <term><varname>$XDG_DATA_DIRS</varname></term>
+
+ <listitem><para>The systemd session
+ manager uses these variables in
+ accordance to the <ulink
+ url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG
+ Base Directory specification</ulink>
+ to find its configuration.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_UNIT_PATH</varname></term>
+
+ <listitem><para>Controls where systemd
+ looks for unit
+ files.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term>
+
+ <listitem><para>Controls where systemd
+ looks for SysV init scripts.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term>
+
+ <listitem><para>Controls where systemd
+ looks for SysV init script runlevel link
+ farms.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$LISTEN_PID</varname></term>
+ <term><varname>$LISTEN_FDS</varname></term>
+
+ <listitem><para>Set by systemd for
+ supervised processes during
+ socket-based activation. See
+ <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for more information.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>$NOTIFY_SOCKET</varname></term>
+
+ <listitem><para>Set by systemd for
+ supervised processes for status and
+ start-up completion notification. See
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for more information.
+ </para></listitem>
+ </varlistentry>
</variablelist>
</refsect1>
</variablelist>
</refsect1>
-
<refsect1>
<title>See Also</title>
<para>
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-install</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff