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[thirdparty/systemd.git] / man / systemd-sysusers.xml

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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!-- SPDX-License-Identifier: LGPL-2.1+ -->

<refentry id="systemd-sysusers"
    xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-sysusers</title>
    <productname>systemd</productname>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-sysusers</refentrytitle>
    <manvolnum>8</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-sysusers</refname>
    <refname>systemd-sysusers.service</refname>
    <refpurpose>Allocate system users and groups</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>systemd-sysusers</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="opt" rep="repeat"><replaceable>CONFIGFILE</replaceable></arg>
    </cmdsynopsis>

    <para><filename>systemd-sysusers.service</filename></para>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>systemd-sysusers</command> creates system users and
    groups, based on the file format and location specified in
    <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
    </para>

    <para>If invoked with no arguments, it applies all directives from all files
    found in the directories specified by
    <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
    When invoked with positional arguments, if option
    <option>--replace=<replaceable>PATH</replaceable></option> is specified, arguments
    specified on the command line are used instead of the configuration file
    <replaceable>PATH</replaceable>. Otherwise, just the configuration specified by
    the command line arguments is executed. The string <literal>-</literal> may be
    specified instead of a filename to instruct <command>systemd-sysusers</command>
    to read the configuration from standard input. If only the basename of a file is
    specified, all configuration directories are searched for a matching file and
    the file found that has the highest priority is executed.</para>
  </refsect1>

  <refsect1>
    <title>Options</title>

    <para>The following options are understood:</para>

    <variablelist>
      <varlistentry>
        <term><option>--root=<replaceable>root</replaceable></option></term>
        <listitem><para>Takes a directory path as an argument. All
        paths will be prefixed with the given alternate
        <replaceable>root</replaceable> path, including config search
        paths. </para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--replace=<replaceable>PATH</replaceable></option></term>
        <listitem><para>When this option is given, one ore more positional arguments
        must be specified. All configuration files found in the directories listed in
        <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
        will be read, and the configuration given on the command line will be
        handled instead of and with the same priority as the configuration file
        <replaceable>PATH</replaceable>.</para>

        <para>This option is intended to be used when package installation scripts
        are running and files belonging to that package are not yet available on
        disk, so their contents must be given on the command line, but the admin
        configuration might already exist and should be given higher priority.
        </para>

        <example>
          <title>RPM installation script for radvd</title>

          <programlisting>echo 'u radvd - "radvd daemon"' | \
          systemd-sysusers --replace=/usr/lib/sysusers.d/radvd.conf -</programlisting>

          <para>This will create the radvd user as if
          <filename>/usr/lib/sysusers.d/radvd.conf</filename> was already on disk.
          An admin might override the configuration specified on the command line by
          placing <filename>/etc/sysusers.d/radvd.conf</filename> or even
          <filename>/etc/sysusers.d/00-overrides.conf</filename>.</para>

          <para>Note that this is the expanded form, and when used in a package, this
          would be written using a macro with "radvd" and a file containing the
          configuration line as arguments.</para>
        </example>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--inline</option></term>
        <listitem><para>Treat each positional argument as a separate configuration
        line instead of a file name.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="cat-config" />
      <xi:include href="standard-options.xml" xpointer="no-pager" />
      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
    </variablelist>

  </refsect1>

  <refsect1>
    <title>Exit status</title>

    <para>On success, 0 is returned, a non-zero failure code
    otherwise.</para>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>sysusers.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <ulink url="https://systemd.io/UIDS-GIDS">Users, Groups, UIDs and GIDs on systemd systems</ulink>
    </para>
  </refsect1>

</refentry>