<?xml version="1.0" encoding="UTF-8"?> <!-- Copyright (c) 1989 - 1990, Julianne Frances Haugh Copyright (c) 2007 - 2008, Nicolas François All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The name of the copyright holders or contributors may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. --> <refentry id='passwd.5'> <!-- $Id$ --> <refmeta> <refentrytitle>passwd</refentrytitle> <manvolnum>5</manvolnum> <refmiscinfo class="sectdesc">File Formats and Conversions</refmiscinfo> </refmeta> <refnamediv id='name'> <refname>passwd</refname> <refpurpose>the password file</refpurpose> </refnamediv> <refsect1 id='description'> <title>DESCRIPTION</title> <para> <filename>/etc/passwd</filename> contains one line for each user account, with seven fields delimited by colons (<quote>:</quote>). These fields are: </para> <itemizedlist mark='bullet'> <listitem> <para>login name</para> </listitem> <listitem> <para>optional encrypted password</para> </listitem> <listitem> <para>numerical user ID</para> </listitem> <listitem> <para>numerical group ID</para> </listitem> <listitem> <para>user name or comment field</para> </listitem> <listitem> <para>user home directory</para> </listitem> <listitem> <para>optional user command interpreter</para> </listitem> </itemizedlist> <para> The encrypted password field may be blank, in which case no password is required to authenticate as the specified login name. However, some applications which read the <filename>/etc/passwd</filename> file may decide not to permit <emphasis>any</emphasis> access at all if the <emphasis>password</emphasis> field is blank. If the <emphasis>password</emphasis> field is a lower-case <quote>x</quote>, then the encrypted password is actually stored in the <citerefentry><refentrytitle>shadow</refentrytitle> <manvolnum>5</manvolnum></citerefentry> file instead; there <emphasis>must</emphasis> be a corresponding line in the <filename>/etc/shadow</filename> file, or else the user account is invalid. If the <emphasis>password</emphasis> field is any other string, then it will be treated as an encrypted password, as specified by <citerefentry><refentrytitle>crypt</refentrytitle> <manvolnum>3</manvolnum></citerefentry>. </para> <para> The comment field is used by various system utilities, such as <citerefentry><refentrytitle>finger</refentrytitle> <manvolnum>1</manvolnum></citerefentry>. </para> <para> The home directory field provides the name of the initial working directory. The <command>login</command> program uses this information to set the value of the <envar>$HOME</envar> environmental variable. </para> <para> The command interpreter field provides the name of the user's command language interpreter, or the name of the initial program to execute. The <command>login</command> program uses this information to set the value of the <envar>$SHELL</envar> environmental variable. If this field is empty, it defaults to the value <filename>/bin/sh</filename>. </para> </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>optional encrypted password file</para> </listitem> </varlistentry> </variablelist> </refsect1> <refsect1 id='see_also'> <title>SEE ALSO</title> <para> <citerefentry> <refentrytitle>crypt</refentrytitle><manvolnum>3</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>getent</refentrytitle><manvolnum>1</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>getpwnam</refentrytitle><manvolnum>3</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>login</refentrytitle><manvolnum>1</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>passwd</refentrytitle><manvolnum>1</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>pwck</refentrytitle><manvolnum>8</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>pwconv</refentrytitle><manvolnum>8</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>pwunconv</refentrytitle><manvolnum>8</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>shadow</refentrytitle><manvolnum>5</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>su</refentrytitle><manvolnum>1</manvolnum> </citerefentry>, <citerefentry> <refentrytitle>sulogin</refentrytitle><manvolnum>8</manvolnum> </citerefentry>. </para> </refsect1> </refentry>