chiark / gitweb /
doc: reword "shared per-thread" wording
[elogind.git] / man / systemd.xml
index ef95641..4abd890 100644 (file)
                                 definition files.</para></listitem>
                         </varlistentry>
                         <varlistentry>
-                                <term><option>--introspect=</option></term>
-
-                                <listitem><para>Extract D-Bus
-                                interface introspection data. This is
-                                mostly useful 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
-                                introspection data for all interfaces
-                                is dumped.</para></listitem>
-                        </varlistentry>
-                        <varlistentry>
                                 <term><option>--unit=</option></term>
 
                                 <listitem><para>Set default unit to
-                                activate on startup. If not specified
+                                activate on startup. If not specified,
                                 defaults to
                                 <filename>default.target</filename>.</para></listitem>
                         </varlistentry>
 
                                 <listitem><para>Highlight important
                                 log messages. Argument is a boolean
-                                value. If the argument is omitted it
+                                value. If the argument is omitted, it
                                 defaults to
                                 <option>true</option>.</para></listitem>
                         </varlistentry>
                 <title>Concepts</title>
 
                 <para>systemd provides a dependency system between
-                various entities called "units". Units encapsulate
-                various objects that are relevant for system boot-up
-                and maintenance. The majority of units are configured
-                in unit configuration files, whose syntax and basic
-                set of options is described in
+                various entities called "units" of 12 different
+                types. Units encapsulate various objects that are
+                relevant for system boot-up and maintenance. The
+                majority of units are configured in unit configuration
+                files, whose syntax and basic set of options is
+                described in
                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                 however some are created automatically from other
-                configuration or dynamically from system state. Units
-                may be 'active' (meaning started, bound, plugged in,
-                ...  depending on the unit type, see below), or
-                'inactive' (meaning stopped, unbound, unplugged, ...),
-                as well as in the process of being activated or
-                deactivated, i.e. between the two states (these states
-                are called 'activating', 'deactivating'). A special
-                'failed' state is available as well which is very
-                similar to 'inactive' and is entered when the service
-                failed in some way (process returned error code on
-                exit, or crashed, or an operation timed out). If this
-                state is entered the cause will be logged, for later
+                configuration, dynamically from system state or
+                programmatically at runtime. Units may be "active"
+                (meaning started, bound, plugged in, ..., depending on
+                the unit type, see below), or "inactive" (meaning
+                stopped, unbound, unplugged, ...), as well as in the
+                process of being activated or deactivated,
+                i.e. between the two states (these states are called
+                "activating", "deactivating"). A special "failed"
+                state is available as well, which is very similar to
+                "inactive" and is entered when the service failed in
+                some way (process returned error code on exit, or
+                crashed, or an operation timed out). If this state is
+                entered, the cause will be logged, for later
                 reference. Note that the various unit types may have a
                 number of additional substates, which are mapped to
                 the five generalized unit states described
                 <para>The following unit types are available:</para>
 
                 <orderedlist>
-                        <listitem><para>Service units, which control
+                        <listitem><para>Service units, which start and control
                         daemons and the processes they consist of. For
                         details see
                         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
                         objects change or are modified. See
                         <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
 
+                        <listitem><para>Slice units may be used to
+                        group units which manage system processes
+                        (such as service and scope units) in a
+                        hierarchical tree for resource management
+                        purposes. See
+                        <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
+
+                        <listitem><para>Scope units are similar to
+                        service units, but manage foreign processes
+                        instead of starting them as well. See
+                        <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem>
+
                 </orderedlist>
 
                 <para>Units are named as their configuration
                 and ordering dependencies are placed between two
                 units. Also note that the majority of dependencies are
                 implicitly created and maintained by systemd. In most
-                cases it should be unnecessary to declare additional
+                cases, it should be unnecessary to declare additional
                 dependencies manually, however it is possible to do
                 this.</para>
 
                 <filename>multi-user.target</filename> (for limited
                 console-only boots for use in embedded or server
                 environments, or similar; a subset of
-                graphical.target). However it is at the discretion of
+                graphical.target). However, it is at the discretion of
                 the administrator to configure it as an alias to any
                 other target unit. See
                 <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                 individual Linux control groups named after the unit
                 which they belong to in the private systemd
                 hierarchy. (see <ulink
-                url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>
+                url="https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink>
                 for more information about control groups, or short
                 "cgroups"). systemd uses this to effectively keep
                 track of processes. Control group information is
 
                 <para>Systemd contains native implementations of
                 various tasks that need to be executed as part of the
-                boot process. For example, it sets the host name or
+                boot process. For example, it sets the hostname or
                 configures the loopback network device. It also sets
                 up and mounts various API file systems, such as
                 <filename>/sys</filename> or
                 <filename>/proc</filename>.</para>
 
                 <para>For more information about the concepts and
-                ideas behind systemd please refer to the <ulink
+                ideas behind systemd, please refer to the <ulink
                 url="http://0pointer.de/blog/projects/systemd.html">Original
                 Design Document</ulink>.</para>
 
 
                                 <para>systemd user managers
                                 treat this signal the same way as
-                                SIGTERM.</para></listitem>
+                                <constant>SIGTERM</constant>.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 option prefixed with
                                 <literal>rd.</literal> is honored
                                 only in the initial RAM disk (initrd),
-                                while the one that isn't prefixed only
+                                while the one that is not prefixed only
                                 in the main system.</para></listitem>
                         </varlistentry>
 
                                 <term><varname>systemd.dump_core=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If <option>true</option>
+                                argument. If <option>true</option>,
                                 systemd dumps core when it
-                                crashes. Otherwise no core dump is
+                                crashes. Otherwise, no core dump is
                                 created. Defaults to
                                 <option>true</option>.</para></listitem>
                         </varlistentry>
                                 <term><varname>systemd.crash_shell=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If <option>true</option>
+                                argument. If <option>true</option>,
                                 systemd spawns a shell when it
-                                crashes. Otherwise no shell is
+                                crashes. Otherwise, no shell is
                                 spawned. Defaults to
                                 <option>false</option>, for security
                                 reasons, as the shell is not protected
                                 <term><varname>systemd.confirm_spawn=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If <option>true</option>
+                                argument. If <option>true</option>,
                                 asks for confirmation when spawning
                                 processes. Defaults to
                                 <option>false</option>.</para></listitem>
                                 <term><varname>systemd.show_status=</varname></term>
 
                                 <listitem><para>Takes a boolean
-                                argument. If <option>true</option>
-                                shows terse service status updates on
-                                the console during bootup. Defaults to
+                                argument or the constant
+                                <constant>auto</constant>. If
+                                <option>true</option>, shows terse
+                                service status updates on the console
+                                during bootup.
+                                <constant>auto</constant> behaves like
+                                <option>false</option> until a service
+                                fails or there is a significant delay
+                                in boot. Defaults to
                                 <option>true</option>, unless
                                 <option>quiet</option> is passed as
                                 kernel command line option in which
                                 case it defaults to
-                                <option>false</option>.</para></listitem>
+                                <constant>auto</constant>.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><varname>systemd.setenv=</varname></term>
 
                                 <listitem><para>Takes a string
-                                argument in the form
-                                VARIABLE=VALUE. May be used to set
-                                environment variables for the init
-                                process and all its children at boot
-                                time. May be used more than once to
-                                set multiple variables. If the equal
-                                sign and variable are missing it unsets
-                                an environment variable which might be
-                                passed in from the initial ram
-                                disk.</para></listitem>
+                                argument in the form VARIABLE=VALUE.
+                                May be used to set default environment
+                                variables to add to forked child processes.
+                                May be used more than once to set multiple
+                                variables.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                         </varlistentry>
 
                         <varlistentry>
+                                <term><varname>-b</varname></term>
                                 <term><varname>emergency</varname></term>
 
                                 <listitem><para>Boot into emergency
         <refsect1>
                 <title>See Also</title>
                 <para>
+                        The <ulink url="http://www.freedesktop.org/wiki/Software/systemd/">systemd Homepage</ulink>,
                         <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,