usr/src/usr.bin/mesg/mesg.1

.\" Copyright (c) 1987 Regents of the University of California.
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.\"     @(#)mesg.1      6.3 (Berkeley) %G%
.\"
.TH MESG 1 ""
.AT 3
.SH NAME
mesg \- permit or deny messages
.SH SYNOPSIS
.B mesg
[
.B n
] [
.B y
]
.SH DESCRIPTION
\fIMesg\fP with argument \fBn\fP forbids messages via \fIwrite\fP
and \fItalk\fP by revoking non-user write permission on the user's
terminal.  \fIMesg\fP with argument \fBy\fP reinstates permission.
\fIMesg\fP without arguments reports the current state without
changing it.
.SH FILES
/dev/tty*
.SH "SEE ALSO"
write(1), talk(1)
.SH DIAGNOSTICS
Exit status is 0 if messages are receivable, 1 if not, -1 on error.