.\"	$OpenBSD: mesg.1,v 1.12 2007/05/31 19:20:13 jmc Exp $
.\"	$NetBSD: mesg.1,v 1.3 1994/12/23 07:16:31 jtc Exp $
.\"
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.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
.\"
.Dd $Mdocdate: May 31 2007 $
.Dt MESG 1
.Os
.Sh NAME
.Nm mesg
.Nd display (do not display) messages from other users
.Sh SYNOPSIS
.Nm mesg
.Op Cm n | Cm y
.Sh DESCRIPTION
The
.Nm mesg
utility is invoked by a user to control write access others
have to the terminal device associated with the standard error
output.
Write access is allowed by default, and programs such as
.Xr talk 1
and
.Xr write 1
may display messages on the terminal.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Cm n
Disallows messages.
.It Cm y
Permits messages to be displayed.
.El
.Pp
If no arguments are given,
.Nm mesg
displays the present message status to the standard error output.
.Pp
The
.Nm mesg
utility exits with one of the following values:
.Bl -tag -width flag -compact -offset indent
.Pp
.It Li "\ 0"
Messages are allowed.
.It Li "\ 1"
Messages are not allowed.
.It Li >1
An error has occurred.
.El
.Sh FILES
.Bl -tag -width /dev/[pt]ty[pq]? -compact
.It Pa /dev/[pt]ty[pq]?
.El
.Sh SEE ALSO
.Xr biff 1 ,
.Xr talk 1 ,
.Xr write 1
.Sh STANDARDS
The
.Nm
utility is compliant with the
.St -p1003.1-2004
specification.
.Sh HISTORY
A
.Nm mesg
command appeared in
.At v2 .