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 May 5, 2002 29.Dt MESG 1 30.Os 31.Sh NAME 32.Nm mesg 33.Nd display (do not display) messages from other users 34.Sh SYNOPSIS 35.Nm 36.Op Cm n | Cm y 37.Sh DESCRIPTION 38The 39.Nm 40utility is invoked by a user to control write access others 41have to a terminal device. 42Write access is allowed by default, and programs such as 43.Xr talk 1 44and 45.Xr write 1 46may display messages on the terminal. 47.Pp 48The first terminal device in the sequence of devices associated with standard 49input, standard output and standard error is affected. 50.Pp 51The following options are available: 52.Bl -tag -width indent 53.It Cm n 54Disallow messages. 55.It Cm y 56Permit messages to be displayed. 57.El 58.Pp 59If no arguments are given, 60.Nm 61displays the present message status to the standard output. 62.Sh EXIT STATUS 63The 64.Nm 65utility exits with one of the following values: 66.Pp 67.Bl -tag -width flag -compact -offset indent 68.It Li "\ 0" 69Messages are allowed. 70.It Li "\ 1" 71Messages are not allowed. 72.It Li ">1" 73An error has occurred. 74.El 75.Sh EXAMPLES 76Disallow messages from other users to the current terminal: 77.Pp 78.Dl "mesg n" 79.Pp 80Allow messages from other users to 81.Pa ttyp1 82(assuming you are also logged in on that terminal): 83.Pp 84.Dl "mesg y </dev/ttyp1" 85.Sh COMPATIBILITY 86Previous versions of the 87.Nm 88utility wrote the message status to the standard error output and 89affected the terminal attached to standard error without first trying the 90standard input or output devices. 91.Sh SEE ALSO 92.Xr biff 1 , 93.Xr talk 1 , 94.Xr wall 1 , 95.Xr write 1 96.Sh STANDARDS 97The 98.Nm 99utility conforms to 100.St -p1003.1-2001 . 101.Sh HISTORY 102A 103.Nm 104command appeared in 105.At v1 . 106