1.\" Copyright (c) 1987, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd December 11, 2020 29.Dt LOCK 1 30.Os 31.Sh NAME 32.Nm lock 33.Nd reserve a terminal 34.Sh SYNOPSIS 35.Nm 36.Op Fl npv 37.Op Fl t Ar timeout 38.Sh DESCRIPTION 39The 40.Nm 41utility requests a password from the user, reads it again for verification 42and then will normally not relinquish the terminal until the password is 43repeated. 44There are two other conditions under which it will terminate: it 45will timeout after some interval of time and it may be killed by someone 46with the appropriate permission. 47.Pp 48The following options are available: 49.Bl -tag -width indent 50.It Fl n 51Do not use a timeout value. 52Terminal will be locked forever. 53.It Fl p 54A password is not requested, instead the user's current login password 55is used. 56.It Fl t Ar timeout 57The time limit (default 15 minutes) is changed to 58.Ar timeout 59minutes. 60.It Fl v 61Disable switching virtual terminals while this terminal is locked. 62This option is implemented in a way similar to the 63.Fl S 64option of 65.Xr vidcontrol 1 , 66and thus has the same restrictions. 67It is only available if the terminal in question is a 68.Xr syscons 4 69or 70.Xr vt 4 71virtual terminal. 72.El 73.Sh EXAMPLES 74Lock the terminal for 5 minutes, disable switching virtual terminals and 75require the user's login password to unlock: 76.Pp 77.Dl $ lock -p -t 5 -v 78.Sh SEE ALSO 79.Xr vidcontrol 1 , 80.Xr syscons 4 , 81.Xr vt 4 82.Sh HISTORY 83The 84.Nm 85command appeared in 86.Bx 3.0 . 87