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.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
.\"
.TH MESG 1 "July 2014" "util-linux" "User Commands"
.SH NAME
mesg \- display (or do not display) messages from other users
.SH SYNOPSIS
.B mesg
[option]
.RB [ n | y ]
.SH DESCRIPTION
The
.B mesg
utility is invoked by a user to control write access others have to the
terminal device associated with 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
The
.B mesg
utility silently exits with error status 2 if not executed on terminal.  In this
case execute
.B mesg
is pointless.  The command line option \fB\-\-verbose\fR forces
mesg to print a warning in this situation.  This behaviour has been introduced
in version 2.33.
.SH ARGUMENTS
.TP
.B n
Disallow messages.
.TP
.B y
Allow messages to be displayed.
.PP
If no arguments are given,
.B mesg
shows the current message status on standard error output.
.SH OPTIONS
.TP
.BR \-v , " \-\-verbose"
Explain what is being done.
.TP
.BR \-V , " \-\-version"
Display version information and exit.
.TP
.BR \-h , " \-\-help"
Display help text and exit.
.SH EXIT STATUS
The
.B mesg
utility exits with one of the following values:
.RS 4
.TP
.B "\ 0"
Messages are allowed.
.TP
.B "\ 1"
Messages are not allowed.
.TP
.B ">1"
An error has occurred.
.RE
.SH FILES
.I /dev/[pt]ty[pq]?
.SH "SEE ALSO"
.BR login (1),
.BR talk (1),
.BR write (1),
.BR wall (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 package and is available from
https://www.kernel.org/pub/linux/utils/util-linux/.
