xref: /freebsd/usr.bin/mesg/mesg.1 (revision a866e170777b42fd7921eadd6e7e664f3a031d60)
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32.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
33.\" $FreeBSD$
34.\"
35.Dd May 5, 2002
36.Dt MESG 1
37.Os
38.Sh NAME
39.Nm mesg
40.Nd display (do not display) messages from other users
41.Sh SYNOPSIS
42.Nm
43.Op Cm n | Cm y
44.Sh DESCRIPTION
45The
46.Nm
47utility is invoked by a user to control write access others
48have to a terminal device.
49Write access is allowed by default, and programs such as
50.Xr talk 1
51and
52.Xr write 1
53may display messages on the terminal.
54.Pp
55The first terminal device in the sequence of devices associated with standard
56input, standard output and standard error is affected.
57.Pp
58The following options are available:
59.Bl -tag -width indent
60.It Cm n
61Disallow messages.
62.It Cm y
63Permit messages to be displayed.
64.El
65.Pp
66If no arguments are given,
67.Nm
68displays the present message status to the standard output.
69.Sh EXAMPLES
70Disallow messages from other users to the current terminal:
71.Pp
72.Dl "mesg n"
73.Pp
74Allow messages from other users to
75.Pa ttyp1
76(assuming you are also logged in on that terminal):
77.Pp
78.Dl "mesg y </dev/ttyp1"
79.Sh EXIT STATUS
80The
81.Nm
82utility exits with one of the following values:
83.Bl -tag -width flag -compact -offset indent
84.Pp
85.It Li "\ 0"
86Messages are allowed.
87.It Li "\ 1"
88Messages are not allowed.
89.It Li ">1"
90An error has occurred.
91.El
92.Sh COMPATIBILITY
93Previous versions of the
94.Nm
95utility wrote the message status to the standard error output and
96affected the terminal attached to standard error without first trying the
97standard input or output devices.
98.Sh SEE ALSO
99.Xr biff 1 ,
100.Xr talk 1 ,
101.Xr wall 1 ,
102.Xr write 1
103.Sh STANDARDS
104The
105.Nm
106utility conforms to
107.St -p1003.1-2001 .
108.Sh HISTORY
109A
110.Nm
111command appeared in
112.At v1 .
113