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.\"	@(#)lock.1	8.1 (Berkeley) 6/6/93
.\"
.Dd December 11, 2020
.Dt LOCK 1
.Os
.Sh NAME
.Nm lock
.Nd reserve a terminal
.Sh SYNOPSIS
.Nm
.Op Fl npv
.Op Fl t Ar timeout
.Sh DESCRIPTION
The
.Nm
utility requests a password from the user, reads it again for verification
and then will normally not relinquish the terminal until the password is
repeated.
There are two other conditions under which it will terminate: it
will timeout after some interval of time and it may be killed by someone
with the appropriate permission.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl n
Do not use a timeout value.
Terminal will be locked forever.
.It Fl p
A password is not requested, instead the user's current login password
is used.
.It Fl t Ar timeout
The time limit (default 15 minutes) is changed to
.Ar timeout
minutes.
.It Fl v
Disable switching virtual terminals while this terminal is locked.
This option is implemented in a way similar to the
.Fl S
option of
.Xr vidcontrol 1 ,
and thus has the same restrictions.
It is only available if the terminal in question is a
.Xr syscons 4
or
.Xr vt 4
virtual terminal.
.El
.Sh EXAMPLES
Lock the terminal for 5 minutes, disable switching virtual terminals and
require the user's login password to unlock:
.Pp
.Dl $ lock -p -t 5 -v
.Sh SEE ALSO
.Xr vidcontrol 1 ,
.Xr syscons 4 ,
.Xr vt 4
.Sh HISTORY
The
.Nm
command appeared in
.Bx 3.0 .