systemd/man/systemd.scope.xml

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<refentry id="systemd.scope">
  <refentryinfo>
    <title>systemd.scope</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.scope</refentrytitle>
    <manvolnum>5</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd.scope</refname>
    <refpurpose>Scope unit configuration</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <para><filename><replaceable>scope</replaceable>.scope</filename></para>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para>Scope units are not configured via unit configuration files,
    but are only created programmatically using the bus interfaces of
    systemd. They are named similar to filenames. A unit whose name
    ends in <literal>.scope</literal> refers to a scope unit. Scopes
    units manage a set of system processes. Unlike service units, scope
    units manage externally created processes, and do not fork off
    processes on its own.</para>

    <para>The main purpose of scope units is grouping worker processes
    of a system service for organization and for managing resources.</para>

    <para><command>systemd-run <option>--scope</option></command> may
    be used to easily launch a command in a new scope unit from the
    command line.</para>

    <para>See the <ulink
    url="https://www.freedesktop.org/wiki/Software/systemd/ControlGroupInterface/">New
    Control Group Interfaces</ulink> for an introduction on how to make
    use of scope units from programs.</para>
  </refsect1>

  <refsect1>
    <title>Automatic Dependencies</title>

    <refsect2>
      <title>Implicit Dependencies</title>

      <para>Implicit dependencies may be added as result of
      resource control parameters as documented in
      <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
    </refsect2>

    <refsect2>
      <title>Default Dependencies</title>

      <para>The following dependencies are added unless
      <varname>DefaultDependencies=no</varname> is set:</para>

      <itemizedlist>
        <listitem><para>Scope units will automatically have dependencies of
        type <varname>Conflicts=</varname> and
        <varname>Before=</varname> on
        <filename>shutdown.target</filename>. These ensure
        that scope units are removed prior to system
        shutdown. Only scope units involved with early boot or
        late system shutdown should disable
        <varname>DefaultDependencies=</varname> option.</para></listitem>
      </itemizedlist>
    </refsect2>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
    </para>
  </refsect1>

</refentry>