xref: /freebsd/usr.bin/mesg/mesg.1 (revision 10b9d77bf1ccf2f3affafa6261692cb92cf7e992)
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28.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
29.\" $FreeBSD$
30.\"
31.Dd May 5, 2002
32.Dt MESG 1
33.Os
34.Sh NAME
35.Nm mesg
36.Nd display (do not display) messages from other users
37.Sh SYNOPSIS
38.Nm
39.Op Cm n | Cm y
40.Sh DESCRIPTION
41The
42.Nm
43utility is invoked by a user to control write access others
44have to a terminal device.
45Write access is allowed by default, and programs such as
46.Xr talk 1
47and
48.Xr write 1
49may display messages on the terminal.
50.Pp
51The first terminal device in the sequence of devices associated with standard
52input, standard output and standard error is affected.
53.Pp
54The following options are available:
55.Bl -tag -width indent
56.It Cm n
57Disallow messages.
58.It Cm y
59Permit messages to be displayed.
60.El
61.Pp
62If no arguments are given,
63.Nm
64displays the present message status to the standard output.
65.Sh EXIT STATUS
66The
67.Nm
68utility exits with one of the following values:
69.Pp
70.Bl -tag -width flag -compact -offset indent
71.It Li "\ 0"
72Messages are allowed.
73.It Li "\ 1"
74Messages are not allowed.
75.It Li ">1"
76An error has occurred.
77.El
78.Sh EXAMPLES
79Disallow messages from other users to the current terminal:
80.Pp
81.Dl "mesg n"
82.Pp
83Allow messages from other users to
84.Pa ttyp1
85(assuming you are also logged in on that terminal):
86.Pp
87.Dl "mesg y </dev/ttyp1"
88.Sh COMPATIBILITY
89Previous versions of the
90.Nm
91utility wrote the message status to the standard error output and
92affected the terminal attached to standard error without first trying the
93standard input or output devices.
94.Sh SEE ALSO
95.Xr biff 1 ,
96.Xr talk 1 ,
97.Xr wall 1 ,
98.Xr write 1
99.Sh STANDARDS
100The
101.Nm
102utility conforms to
103.St -p1003.1-2001 .
104.Sh HISTORY
105A
106.Nm
107command appeared in
108.At v1 .
109