shadow/man/chsh.1.xml

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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 CHSH_AUTH             SYSTEM "login.defs.d/CHSH_AUTH.xml">
<!ENTITY LOGIN_STRING          SYSTEM "login.defs.d/LOGIN_STRING.xml">
]>

<refentry id='chsh.1'>
  <!-- $Id$ -->
  <refmeta>
    <refentrytitle>chsh</refentrytitle>
    <manvolnum>1</manvolnum>
    <refmiscinfo class="sectdesc">User Commands</refmiscinfo>
  </refmeta>
  <refnamediv id='name'>
    <refname>chsh</refname>
    <refpurpose>change login shell</refpurpose>
  </refnamediv>

  <refsynopsisdiv id='synopsis'>
    <cmdsynopsis>
      <command>chsh</command>
      <arg choice='opt'>
	<replaceable>options</replaceable>
      </arg>
      <arg choice='opt'>
        <replaceable>LOGIN</replaceable>
      </arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id='description'>
    <title>DESCRIPTION</title>
    <para>
      The <command>chsh</command> command changes the user login shell.
      This determines the name of the user's initial login command. A normal
      user may only change the login shell for her own account; the
      superuser may change the login shell for any account.
    </para>

  </refsect1>

  <refsect1 id='options'>
    <title>OPTIONS</title>
    <para>
      The options which apply to the <command>chsh</command> command are:
    </para>
    <variablelist remap='IP'>
      <varlistentry>
	<term><option>-h</option>, <option>--help</option></term>
	<listitem>
	  <para>Display help message and exit.</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term>
	  <option>-s</option>, <option>--shell</option> <replaceable>SHELL</replaceable>
	</term>
        <listitem>                                                                                                                   
	  <para>
	    The name of the user's new login shell. Setting this field to
	    blank causes the system to select the default login shell.
	  </para>
	</listitem>
      </varlistentry>
    </variablelist>
    <para>
      If the <option>-s</option> option is not selected,
      <command>chsh</command> operates in an interactive fashion, prompting
      the user with the current login shell. Enter the new value to change
      the shell, or leave the line blank to use the current one. The current
      shell is displayed between a pair of <emphasis>[ ]</emphasis> marks.
    </para>
  </refsect1>

  <refsect1 id='note'>
    <title>NOTE</title>
    <para>
      The only restriction placed on the login shell is that the command
      name must be listed in <filename>/etc/shells</filename>, unless the
      invoker is the superuser, and then any value may be added. An
      account with a restricted login shell may not change her login shell.
      For this reason, placing <filename>/bin/rsh</filename> in
      <filename>/etc/shells</filename> is discouraged since accidentally
      changing to a restricted shell would prevent the user from ever
      changing her login shell back to its original value.
    </para>
  </refsect1>

  <refsect1 id='configuration' condition="no_pam">
    <title>CONFIGURATION</title>
    <para>
      The following configuration variables in
      <filename>/etc/login.defs</filename> change the behavior of this
      tool:
    </para>
    <variablelist>
      &CHSH_AUTH;
      &LOGIN_STRING;
    </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/shells</filename></term>
	<listitem>
	  <para>List of valid login shells.</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><filename>/etc/login.defs</filename></term>
	<listitem>
	  <para>Shadow password suite configuration.</para>
	</listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='see_also'>
    <title>SEE ALSO</title>
    <para>
      <citerefentry>
	<refentrytitle>chfn</refentrytitle><manvolnum>1</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>login.defs</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry>,
      <citerefentry>
	<refentrytitle>passwd</refentrytitle><manvolnum>5</manvolnum>
      </citerefentry>.
    </para>
  </refsect1>
</refentry>