'\" t
.\"     Title: sulogin
.\"    Author: [see the "AUTHOR(S)" section]
.\" Generator: Asciidoctor 2.0.15
.\"      Date: 2022-02-17
.\"    Manual: System Administration
.\"    Source: util-linux 2.38
.\"  Language: English
.\"
.TH "SULOGIN" "8" "2022-02-17" "util\-linux 2.38" "System Administration"
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.SH "NAME"
sulogin \- single\-user login
.SH "SYNOPSIS"
.sp
\fBsulogin\fP [options] [\fItty\fP]
.SH "DESCRIPTION"
.sp
\fBsulogin\fP is invoked by \fBinit\fP when the system goes into single\-user mode.
.sp
The user is prompted:
.sp
Give root password for system maintenance (or type Control\-D for normal startup):
.sp
If the root account is locked and \fB\-\-force\fP is specified, no password is required.
.sp
\fBsulogin\fP will be connected to the current terminal, or to the optional \fItty\fP device that can be specified on the command line (typically \fI/dev/console\fP).
.sp
When the user exits from the single\-user shell, or presses control\-D at the prompt, the system will continue to boot.
.SH "OPTIONS"
.sp
\fB\-e\fP, \fB\-\-force\fP
.RS 4
If the default method of obtaining the root password from the system via \fBgetpwnam\fP(3) fails, then examine \fI/etc/passwd\fP and \fI/etc/shadow\fP to get the password. If these files are damaged or nonexistent, or when root account is locked by \(aq!\(aq or \(aq*\(aq at the begin of the password then \fBsulogin\fP will \fBstart a root shell without asking for a password\fP.
.sp
Only use the \fB\-e\fP option if you are sure the console is physically protected against unauthorized access.
.RE
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\fB\-p\fP, \fB\-\-login\-shell\fP
.RS 4
Specifying this option causes \fBsulogin\fP to start the shell process as a login shell.
.RE
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\fB\-t\fP, \fB\-\-timeout\fP \fIseconds\fP
.RS 4
Specify the maximum amount of time to wait for user input. By default, \fBsulogin\fP will wait forever.
.RE
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\fB\-h\fP, \fB\-\-help\fP
.RS 4
Display help text and exit.
.RE
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\fB\-V\fP, \fB\-\-version\fP
.RS 4
Print version and exit.
.RE
.SH "ENVIRONMENT"
.sp
\fBsulogin\fP looks for the environment variable \fBSUSHELL\fP or \fBsushell\fP to determine what shell to start. If the environment variable is not set, it will try to execute root\(cqs shell from \fI/etc/passwd\fP. If that fails, it will fall back to \fI/bin/sh\fP.
.SH "AUTHORS"
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\fBsulogin\fP was written by Miquel van Smoorenburg for sysvinit and later ported to util\-linux by Dave Reisner and Karel Zak.
.SH "REPORTING BUGS"
.sp
For bug reports, use the issue tracker at \c
.URL "https://github.com/util\-linux/util\-linux/issues" "" "."
.SH "AVAILABILITY"
.sp
The \fBsulogin\fP command is part of the util\-linux package which can be downloaded from \c
.URL "https://www.kernel.org/pub/linux/utils/util\-linux/" "Linux Kernel Archive" "."