1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
|
<?xml version="1.0" encoding="UTF-8"?>
<!--
Copyright (c) 1989 - 1992, 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.
-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
<!ENTITY ENV_HZ SYSTEM "login.defs.d/ENV_HZ.xml">
<!ENTITY ENV_TZ SYSTEM "login.defs.d/ENV_TZ.xml">
<!-- SHADOW-CONFIG-HERE -->
]>
<refentry id='sulogin.8'>
<!-- $Id$ -->
<refentryinfo>
<author>
<firstname>Julianne Frances</firstname>
<surname>Haugh</surname>
<contrib>Creation, 1989</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>sulogin</refentrytitle>
<manvolnum>8</manvolnum>
<refmiscinfo class="sectdesc">System Management Commands</refmiscinfo>
<refmiscinfo class="source">shadow-utils</refmiscinfo>
<refmiscinfo class="version">&SHADOW_UTILS_VERSION;</refmiscinfo>
</refmeta>
<refnamediv id='name'>
<refname>sulogin</refname>
<refpurpose>Single-user login</refpurpose>
</refnamediv>
<refsect1 id='syntax'>
<title>SYNTAX</title>
<para><command>sulogin</command> [<emphasis remap='I'>tty-device</emphasis>]
</para>
</refsect1>
<refsect1 id='description'>
<title>DESCRIPTION</title>
<para>
The <command>sulogin</command> command is invoked by <command>init</command>
prior to allowing the user access to the system when in single user mode.
This feature may only be available on certain systems where
<command>init</command> has been modified accordingly, or where the
<filename>/etc/inittab</filename> has an entry for a single user
login.
</para>
<para>The user is prompted</para>
<para>Type control-d to proceed with normal startup,
<!-- .br -->
(or give root password for system maintenance):
</para>
<para>
Input and output will be performed with the standard file descriptors
unless the optional device name argument is provided.
</para>
<para>
If the user enters the correct root password, a login session is
initiated. When <emphasis>EOF</emphasis> is pressed instead, the
system enters multi-user mode.
</para>
<para>
After the user exits the single-user shell, or presses
<emphasis>EOF</emphasis>, the system begins the initialization process
required to enter multi-user mode.
</para>
</refsect1>
<refsect1 id='caveats'>
<title>CAVEATS</title>
<para>
This command can only be used if <command>init</command> has been
modified to call <command>sulogin</command> instead of
<filename>/bin/sh</filename>, or if the user has set the <emphasis
remap='I'>inittab</emphasis> to support a single user login. For
example, the line:
</para>
<para>co:s:respawn:/etc/sulogin /dev/console</para>
<para>should execute the sulogin command in single user mode.</para>
<para>
As complete an environment as possible is created. However, various
devices may be unmounted or uninitialized and many of the user
commands may be unavailable or nonfunctional as a result.
</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>
&ENV_HZ;
&ENV_TZ;
</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>
</variablelist>
</refsect1>
<refsect1 id='see_also'>
<title>SEE ALSO</title>
<para>
<citerefentry>
<refentrytitle>login</refentrytitle><manvolnum>1</manvolnum>
</citerefentry>,
<citerefentry>
<refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum>
</citerefentry>,
<citerefentry>
<refentrytitle>init</refentrytitle><manvolnum>8</manvolnum>
</citerefentry>.
</para>
</refsect1>
</refentry>
|
