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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)mesg.1 8.1 (Berkeley) 6/6/93 33.\" $FreeBSD$ 34.\" 35.Dd May 5, 2002 36.Dt MESG 1 37.Os 38.Sh NAME 39.Nm mesg 40.Nd display (do not display) messages from other users 41.Sh SYNOPSIS 42.Nm 43.Op Cm n | Cm y 44.Sh DESCRIPTION 45The 46.Nm 47utility is invoked by a user to control write access others 48have to a terminal device. 49Write access is allowed by default, and programs such as 50.Xr talk 1 51and 52.Xr write 1 53may display messages on the terminal. 54.Pp 55The first terminal device in the sequence of devices associated with standard 56input, standard output and standard error is affected. 57.Pp 58The following options are available: 59.Bl -tag -width indent 60.It Cm n 61Disallow messages. 62.It Cm y 63Permit messages to be displayed. 64.El 65.Pp 66If no arguments are given, 67.Nm 68displays the present message status to the standard output. 69.Sh EXAMPLES 70Disallow messages from other users to the current terminal: 71.Pp 72.Dl "mesg n" 73.Pp 74Allow messages from other users to 75.Pa ttyp1 76(assuming you are also logged in on that terminal): 77.Pp 78.Dl "mesg y </dev/ttyp1" 79.Sh DIAGNOSTICS 80The 81.Nm 82utility exits with one of the following values: 83.Bl -tag -width flag -compact -offset indent 84.Pp 85.It Li "\ 0" 86Messages are allowed. 87.It Li "\ 1" 88Messages are not allowed. 89.It Li ">1" 90An error has occurred. 91.El 92.Sh COMPATIBILITY 93Previous versions of the 94.Nm 95utility wrote the message status to the standard error output and 96affected the terminal attached to standard error without first trying the 97standard input or output devices. 98.Sh SEE ALSO 99.Xr biff 1 , 100.Xr talk 1 , 101.Xr wall 1 , 102.Xr write 1 103.Sh STANDARDS 104The 105.Nm 106utility conforms to 107.St -p1003.1-2001 . 108.Sh HISTORY 109A 110.Nm 111command appeared in 112.At v1 . 113