udev: kmod, hwdb - do not fail if databases are not available

[thirdparty/systemd.git] / man / systemd-suspend.service.xml

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<refentry id="systemd-suspend.service">

        <refentryinfo>
                <title>systemd-suspend.service</title>
                <productname>systemd</productname>

                <authorgroup>
                        <author>
                                <contrib>Developer</contrib>
                                <firstname>Lennart</firstname>
                                <surname>Poettering</surname>
                                <email>lennart@poettering.net</email>
                        </author>
                </authorgroup>
        </refentryinfo>

        <refmeta>
                <refentrytitle>systemd-suspend.service</refentrytitle>
                <manvolnum>8</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>systemd-suspend.service</refname>
                <refname>systemd-hibernate.service</refname>
                <refname>systemd-sleep</refname>
                <refpurpose>System sleep state logic</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <para><filename>systemd-suspend.service</filename></para>
                <para><filename>systemd-hibernate.service</filename></para>
                <para><filename>/usr/lib/systemd/systemd-sleep</filename></para>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para><filename>systemd-suspend.service</filename> is
                a system service that is pulled in by
                <filename>suspend.target</filename> and is responsible
                for the actual system suspend. Similar,
                <filename>systemd-hibernate.service</filename> is
                pulled in by <filename>hibernate.target</filename> to
                executed the actual hibernation.</para>

                <para>Immediately before entering system suspend and
                hibernation
                <filename>systemd-suspend.service</filename> will run
                all executables in
                <filename>/usr/lib/systemd/system-sleep/</filename>
                and pass two arguments to them. The first argument
                will be "<literal>pre</literal>", the second either
                "<literal>suspend</literal>" or
                "<literal>hibernate</literal>", depending on the
                chosen action. Immediately after leaving system
                suspend and hibernation the same executables are run,
                but the first argument is now
                "<literal>post</literal>". All executables in this
                directory are executed in parallel, and execution of
                the action is not continued before all executables
                finished.</para>

                <para>Note that scripts or binaries dropped in
                <filename>/usr/lib/systemd/system-sleep/</filename>
                are intended for local use only and should be
                considered hacks. If applications want to be notified
                of system suspend and resume there are much nicer
                interfaces available.</para>

                <para>Note that
                <filename>systemd-suspend.service</filename> and
                <filename>systemd-hibernate.service</filename> should
                never be executed directly. Instead, trigger system
                sleep states with a command such as "<literal>systemctl
                suspend</literal>" or suchlike.</para>
        </refsect1>

        <refsect1>
                <title>See Also</title>
                <para>
                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>systemd-halt.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                </para>
        </refsect1>

</refentry>