man: document that start limiting of GC'ed units doesn't work (#7337)

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

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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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<refentry id="systemd-logind.service" conditional='ENABLE_LOGIND'>

  <refentryinfo>
    <title>systemd-logind.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-logind.service</refentrytitle>
    <manvolnum>8</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-logind.service</refname>
    <refname>systemd-logind</refname>
    <refpurpose>Login manager</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <para><filename>systemd-logind.service</filename></para>
    <para><filename>/usr/lib/systemd/systemd-logind</filename></para>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>systemd-logind</command> is a system service that
    manages user logins. It is responsible for:</para>

    <itemizedlist>
      <listitem><para>Keeping track of users and sessions, their processes and their idle state. This is implemented by
      allocating a systemd slice unit for each user below <filename>user.slice</filename>, and a scope unit below it
      for each concurrent session of a user. Also, a per-user service manager is started as system service instance of
      <filename>user@.service</filename> for each logged in user.</para></listitem>

      <listitem><para>Generating and managing session IDs. If auditing is available and an audit session ID is already set for
      a session, then this ID is reused as the session ID. Otherwise, an independent session counter is
      used.</para></listitem>

      <listitem><para>Providing PolicyKit-based access for users for
      operations such as system shutdown or sleep</para></listitem>

      <listitem><para>Implementing a shutdown/sleep inhibition logic
      for applications</para></listitem>

      <listitem><para>Handling of power/sleep hardware
      keys</para></listitem>

      <listitem><para>Multi-seat management</para></listitem>

      <listitem><para>Session switch management</para></listitem>

      <listitem><para>Device access management for
      users</para></listitem>

      <listitem><para>Automatic spawning of text logins (gettys) on
      virtual console activation and user runtime directory
      management</para></listitem>
    </itemizedlist>

    <para>User sessions are registered with logind via the
    <citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    PAM module.</para>

    <para>See
    <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
    for information about the configuration of this service.</para>

    <para>See <ulink
    url="https://www.freedesktop.org/wiki/Software/systemd/multiseat">Multi-Seat
    on Linux</ulink> for an introduction into basic concepts of logind
    such as users, sessions and seats.</para>

    <para>See the <ulink
    url="https://www.freedesktop.org/wiki/Software/systemd/logind">
    logind D-Bus API Documentation</ulink> for information about the
    APIs <filename>systemd-logind</filename> provides.</para>

    <para>For more information on the inhibition logic see the <ulink
    url="https://www.freedesktop.org/wiki/Software/systemd/inhibit">Inhibitor
    Lock Developer Documentation</ulink>.</para>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-user-sessions.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>pam_systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    </para>
  </refsect1>

</refentry>