shadow/man/newgrp.1.xml

<?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='newgrp.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>newgrp</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>newgrp</refname>
    <refpurpose>log in to a new group</refpurpose>
  </refnamediv>
  <!-- body begins here -->
  <refsynopsisdiv id='synopsis'>
    <cmdsynopsis>
      <command>newgrp</command>    <arg choice='opt'>- </arg>
      <arg choice='opt'><replaceable>group</replaceable></arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id='description'>
  <title>DESCRIPTION</title>
    <para>
      The <command>newgrp</command> command is used to change the current
      group ID during a login session. If the optional <option>-</option>
      flag is given, the user's environment will be reinitialized as though
      the user had logged in, otherwise the current environment, including
      current working directory, remains unchanged.
    </para>

    <para>
      <command>newgrp</command> changes the current real group ID to the
      named group, or to the default group listed in
      <filename>/etc/passwd</filename> if no group name is given. 
      <command>newgrp</command> also tries to add the group to the user
      groupset. If not root, the user will be prompted for a password if she
      does not have a password (in <filename>/etc/shadow</filename> if this
      user has an entry in the shadowed password file, or in
      <filename>/etc/passwd</filename> otherwise) and the group does, or if
      the user is not listed as a member and the group has a password. The
      user will be denied access if the group password is empty and the user
      is not listed as a member.
    </para>

    <para condition="gshadow">
      If there is an entry for this group in
      <filename>/etc/gshadow</filename>, then the list of members and the
      password of this group will be taken from this file, otherwise, the
      entry in <filename>/etc/group</filename> is considered.
    </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>su</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>sg</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 condition="gshadow">
	  <refentrytitle>gshadow</refentrytitle><manvolnum>5</manvolnum>
	</citerefentry>
      </phrase>.
    </para>
  </refsect1>
</refentry>