shadow/man/sulogin.8

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.\" Copyright 1989 - 1992, Julianne Frances Haugh
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.\" $Id: sulogin.8,v 1.5 2000/08/26 18:27:17 marekm Exp $
.\"
.TH SULOGIN 8
.SH NAME
sulogin \- Single-user login
.SH SYNTAX
\fBsulogin\fR [\fItty-device\fR]
.SH DESCRIPTION
.B sulogin
is invoked by \fBinit\fR prior to allowing the user
access to the system when in single user mode.
This feature may only be available on certain systems where
\fBinit\fR has been modified accordingly, or where the
\fB/etc/inittab\fR has an entry for a single user login.
.PP
The user is prompted
.IP "" .5i
Type control-d to proceed with normal startup,
.br
(or give root password for system maintenance):
.PP
Input and output will be performed with the standard file
descriptors unless the optional device name argument is provided.
.PP
If the user enters the correct root password, a login session
is initiated.
When \fBEOF\fR is pressed instead, the system enters multi-user
mode.
.PP
After the user exits the single-user shell, or presses \fBEOF\fR,
the system begins the initialization process required to enter
multi-user mode.
.SH CAVEATS
.PP
This command can only be used if \fBinit\fR has been modified to call
\fBsulogin\fR instead of \fB/bin/sh\fR,
or if the user has set the \fIinittab\fR to support a single user
login.
For example, the line
.br
.sp 1
co:s:respawn:/etc/sulogin /dev/console
.br
.sp 1
should execute the sulogin command in single user mode.
.PP
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.
.SH FILES
/etc/passwd \- user account information
.br
/etc/shadow \- encrypted passwords and age information
.br
/.profile \- initialization script for single user shell
.SH SEE ALSO
.BR login (1),
.BR init (8),
.BR sh (1)
.SH AUTHOR
Julianne Frances Haugh (jfh@austin.ibm.com)