xref: /freebsd/usr.bin/mesg/mesg.1 (revision fd45b686f9d92f583366c75b22c04c7ee49709c0)
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28.Dd May 5, 2002
29.Dt MESG 1
30.Os
31.Sh NAME
32.Nm mesg
33.Nd display (do not display) messages from other users
34.Sh SYNOPSIS
35.Nm
36.Op Cm n | Cm y
37.Sh DESCRIPTION
38The
39.Nm
40utility is invoked by a user to control write access others
41have to a terminal device.
42Write access is allowed by default, and programs such as
43.Xr talk 1
44and
45.Xr write 1
46may display messages on the terminal.
47.Pp
48The first terminal device in the sequence of devices associated with standard
49input, standard output and standard error is affected.
50.Pp
51The following options are available:
52.Bl -tag -width indent
53.It Cm n
54Disallow messages.
55.It Cm y
56Permit messages to be displayed.
57.El
58.Pp
59If no arguments are given,
60.Nm
61displays the present message status to the standard output.
62.Sh EXIT STATUS
63The
64.Nm
65utility exits with one of the following values:
66.Pp
67.Bl -tag -width flag -compact -offset indent
68.It Li "\ 0"
69Messages are allowed.
70.It Li "\ 1"
71Messages are not allowed.
72.It Li ">1"
73An error has occurred.
74.El
75.Sh EXAMPLES
76Disallow messages from other users to the current terminal:
77.Pp
78.Dl "mesg n"
79.Pp
80Allow messages from other users to
81.Pa ttyp1
82(assuming you are also logged in on that terminal):
83.Pp
84.Dl "mesg y </dev/ttyp1"
85.Sh COMPATIBILITY
86Previous versions of the
87.Nm
88utility wrote the message status to the standard error output and
89affected the terminal attached to standard error without first trying the
90standard input or output devices.
91.Sh SEE ALSO
92.Xr biff 1 ,
93.Xr talk 1 ,
94.Xr wall 1 ,
95.Xr write 1
96.Sh STANDARDS
97The
98.Nm
99utility conforms to
100.St -p1003.1-2001 .
101.Sh HISTORY
102A
103.Nm
104command appeared in
105.At v1 .
106