xref: /freebsd/usr.bin/mesg/mesg.1 (revision 4f8f43b06ed07e96a250855488cc531799d5b78f)
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28.\"	@(#)mesg.1	8.1 (Berkeley) 6/6/93
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30.Dd May 5, 2002
31.Dt MESG 1
32.Os
33.Sh NAME
34.Nm mesg
35.Nd display (do not display) messages from other users
36.Sh SYNOPSIS
37.Nm
38.Op Cm n | Cm y
39.Sh DESCRIPTION
40The
41.Nm
42utility is invoked by a user to control write access others
43have to a terminal device.
44Write access is allowed by default, and programs such as
45.Xr talk 1
46and
47.Xr write 1
48may display messages on the terminal.
49.Pp
50The first terminal device in the sequence of devices associated with standard
51input, standard output and standard error is affected.
52.Pp
53The following options are available:
54.Bl -tag -width indent
55.It Cm n
56Disallow messages.
57.It Cm y
58Permit messages to be displayed.
59.El
60.Pp
61If no arguments are given,
62.Nm
63displays the present message status to the standard output.
64.Sh EXIT STATUS
65The
66.Nm
67utility exits with one of the following values:
68.Pp
69.Bl -tag -width flag -compact -offset indent
70.It Li "\ 0"
71Messages are allowed.
72.It Li "\ 1"
73Messages are not allowed.
74.It Li ">1"
75An error has occurred.
76.El
77.Sh EXAMPLES
78Disallow messages from other users to the current terminal:
79.Pp
80.Dl "mesg n"
81.Pp
82Allow messages from other users to
83.Pa ttyp1
84(assuming you are also logged in on that terminal):
85.Pp
86.Dl "mesg y </dev/ttyp1"
87.Sh COMPATIBILITY
88Previous versions of the
89.Nm
90utility wrote the message status to the standard error output and
91affected the terminal attached to standard error without first trying the
92standard input or output devices.
93.Sh SEE ALSO
94.Xr biff 1 ,
95.Xr talk 1 ,
96.Xr wall 1 ,
97.Xr write 1
98.Sh STANDARDS
99The
100.Nm
101utility conforms to
102.St -p1003.1-2001 .
103.Sh HISTORY
104A
105.Nm
106command appeared in
107.At v1 .
108