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.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
.\"
.\" Fri Mar 10 20:31:02 1995, modified for standard man macros,
.\" faith@cs.unc.edu
.\"
.\"
.\" "
.TH MESG 1 "10 March 1995" "Linux 1.2" "Linux Programmer's Manual"
.SH NAME
mesg \- display (do not display) messages from other users
.SH SYNOPSIS
.B mesg
.RB [ n | y ]
.SH DESCRIPTION
The
.B mesg
utility is invoked by a users to control write access others have to the
terminal device associated with the standard error output.  If write access
is allowed, then programs such as
.BR talk (1)
and
.BR write (1)
may display messages on the terminal.
.PP
Traditionally, write access is allowed by default.  However, as users
become more conscious of various security risks, there is a trend to remove
write access by default, at least for the primary login shell.  To make
sure your ttys are set the way you want them to be set,
.B mesg
should be executed in your login scripts.
.PP
Options available:
.TP
.B n
Disallows messages.
.TP
.B y
Permits messages to be displayed.
.PP
If no arguments are given,
.B mesg
displays the present message status to the standard error output.
.PP
The
.B mesg
utility exits with one of the following values:
.TP
.I "\ 0"
Messages are allowed.
.TP
.I "\ 1"
Messages are not allowed.
.TP
.I "\>1"
An error has occurred.
.SH FILES
.I /dev/[pt]ty[pq]?
.SH "SEE ALSO"
.BR biff (1),
.BR talk (1),
.BR write (1),
.BR wall (1),
.BR login (1),
.BR xterm (1)
.SH HISTORY
A
.B mesg
command appeared in Version 6 AT&T UNIX.

.SH AVAILABILITY
The mesg command is part of the util-linux-ng package and is available from
ftp://ftp.kernel.org/pub/linux/utils/util-linux-ng/.