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.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
.\" $FreeBSD$
.\"
.Dd May 5, 2002
.Dt MESG 1
.Os
.Sh NAME
.Nm mesg
.Nd display (do not display) messages from other users
.Sh SYNOPSIS
.Nm
.Op Cm n | Cm y
.Sh DESCRIPTION
The
.Nm
utility is invoked by a user to control write access others
have to a terminal device.
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 first terminal device in the sequence of devices associated with standard
input, standard output and standard error is affected.
.Pp
The following options are available:
.Bl -tag -width indent
.It Cm n
Disallow messages.
.It Cm y
Permit messages to be displayed.
.El
.Pp
If no arguments are given,
.Nm
displays the present message status to the standard output.
.Sh EXIT STATUS
The
.Nm
utility exits with one of the following values:
.Pp
.Bl -tag -width flag -compact -offset indent
.It Li "\ 0"
Messages are allowed.
.It Li "\ 1"
Messages are not allowed.
.It Li ">1"
An error has occurred.
.El
.Sh EXAMPLES
Disallow messages from other users to the current terminal:
.Pp
.Dl "mesg n"
.Pp
Allow messages from other users to
.Pa ttyp1
(assuming you are also logged in on that terminal):
.Pp
.Dl "mesg y </dev/ttyp1"
.Sh COMPATIBILITY
Previous versions of the
.Nm
utility wrote the message status to the standard error output and
affected the terminal attached to standard error without first trying the
standard input or output devices.
.Sh SEE ALSO
.Xr biff 1 ,
.Xr talk 1 ,
.Xr wall 1 ,
.Xr write 1
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.1-2001 .
.Sh HISTORY
A
.Nm
command appeared in
.At v1 .