<?xml version="1.0" encoding="UTF-8"?>
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   Copyright (c) 1991       , Julianne Frances Haugh
   Copyright (c) 2007 - 2008, Nicolas François
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
<!ENTITY SYSLOG_SG_ENAB        SYSTEM "login.defs.d/SYSLOG_SG_ENAB.xml">
<!-- SHADOW-CONFIG-HERE -->
]>
<refentry id='sg.1'>
  <!-- $Id$ -->
  <refentryinfo>
    <author>
      <firstname>Julianne Frances</firstname>
      <surname>Haugh</surname>
      <contrib>Creation, 1991</contrib>
    </author>
    <author>
      <firstname>Thomas</firstname>
      <surname>Kłoczko</surname>
      <email>kloczek@pld.org.pl</email>
      <contrib>shadow-utils maintainer, 2000 - 2007</contrib>
    </author>
    <author>
      <firstname>Nicolas</firstname>
      <surname>François</surname>
      <email>nicolas.francois@centraliens.net</email>
      <contrib>shadow-utils maintainer, 2007 - now</contrib>
    </author>
  </refentryinfo>
  <refmeta>
    <refentrytitle>sg</refentrytitle>
    <manvolnum>1</manvolnum>
    <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
    <refmiscinfo class="source">shadow-utils</refmiscinfo>
    <refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo>
  </refmeta>
  <refnamediv id='name'>
    <refname>sg</refname>
    <refpurpose>execute command as different group ID</refpurpose>
  </refnamediv>
  <!-- body begins here -->
  <refsynopsisdiv id='synopsis'>
    <cmdsynopsis>
      <command>sg</command>
      <arg choice='opt'>- </arg>
      <arg choice='opt'>group
	<arg choice='opt'>-c </arg>
	command
      </arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id='description'>
  <title>DESCRIPTION</title>
    <para>
      The <command>sg</command> command works similar to
      <command>newgrp</command> but accepts a command. The command will be
      executed with the <filename>/bin/sh</filename> shell. With most shells
      you may run <command>sg</command> from, you need to enclose multi-word
      commands in quotes. Another difference between
      <command>newgrp</command> and <command>sg</command> is that some
      shells treat <command>newgrp</command> specially, replacing themselves
      with a new instance of a shell that <command>newgrp</command> creates.
      This doesn't happen with <command>sg</command>, so upon exit from a
      <command>sg</command> command you are returned to your previous group
      ID.
    </para>
  </refsect1>

  <refsect1 id='configuration'>
    <title>CONFIGURATION</title>
    <para>
      The following configuration variables in
      <filename>/etc/login.defs</filename> change the behavior of this
      tool:
    </para>
    <variablelist>
      &SYSLOG_SG_ENAB;
    </variablelist>
  </refsect1>

  <refsect1 id='files'>
    <title>FILES</title>
    <variablelist>
      <varlistentry>
	<term><filename>/etc/passwd</filename></term>
	<listitem>
	  <para>User account information.</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><filename>/etc/shadow</filename></term>
	<listitem>
	  <para>Secure user account information.</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><filename>/etc/group</filename></term>
	<listitem>
	  <para>Group account information.</para>
	 </listitem>
      </varlistentry>
      <varlistentry condition="gshadow">
	<term><filename>/etc/gshadow</filename></term>
	<listitem>
	  <para>Secure group account information.</para>
	</listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='see_also'>
    <title>SEE ALSO</title>
    <para>
      <citerefentry>
	<refentrytitle>id</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>login</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>newgrp</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>su</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>gpasswd</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>group</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry><phrase condition="gshadow">,
	<citerefentry>
	  <refentrytitle>gshadow</refentrytitle><manvolnum>5</manvolnum>
	</citerefentry>
      </phrase>.
    </para>
  </refsect1>
</refentry>