term-utils/mesg.1

   1 .\" Copyright (c) 1987, 1990, 1993
   2 .\"     The Regents of the University of California.  All rights reserved.
   3 .\"
   4 .\" Redistribution and use in source and binary forms, with or without
   5 .\" modification, are permitted provided that the following conditions
   6 .\" are met:
   7 .\" 1. Redistributions of source code must retain the above copyright
   8 .\"    notice, this list of conditions and the following disclaimer.
   9 .\" 2. Redistributions in binary form must reproduce the above copyright
  10 .\"    notice, this list of conditions and the following disclaimer in the
  11 .\"    documentation and/or other materials provided with the distribution.
  12 .\" 3. All advertising materials mentioning features or use of this software
  13 .\"    must display the following acknowledgement:
  14 .\"     This product includes software developed by the University of
  15 .\"     California, Berkeley and its contributors.
  16 .\" 4. Neither the name of the University nor the names of its contributors
  17 .\"    may be used to endorse or promote products derived from this software
  18 .\"    without specific prior written permission.
  19 .\"
  20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30 .\" SUCH DAMAGE.
  31 .\"
  32 .\"     @(#)mesg.1      8.1 (Berkeley) 6/6/93
  33 .\"
  34 .TH MESG 1 "July 2014" "util-linux" "User Commands"
  35 .SH NAME
  36 mesg \- display (or do not display) messages from other users
  37 .SH SYNOPSIS
  38 .B mesg
  39 [option]
  40 .RB [ n | y ]
  41 .SH DESCRIPTION
  42 The
  43 .B mesg
  44 utility is invoked by a user to control write access others have to the
  45 terminal device associated with standard error output.  If write access
  46 is allowed, then programs such as
  47 .BR talk (1)
  48 and
  49 .BR write (1)
  50 may display messages on the terminal.
  51 .PP
  52 Traditionally, write access is allowed by default.  However, as users
  53 become more conscious of various security risks, there is a trend to remove
  54 write access by default, at least for the primary login shell.  To make
  55 sure your ttys are set the way you want them to be set,
  56 .B mesg
  57 should be executed in your login scripts.
  58 .SH ARGUMENTS
  59 .TP
  60 .B n
  61 Disallow messages.
  62 .TP
  63 .B y
  64 Allow messages to be displayed.
  65 .PP
  66 If no arguments are given,
  67 .B mesg
  68 shows the current message status on standard error output.
  69 .SH OPTIONS
  70 .TP
  71 .BR \-v , " \-\-verbose"
  72 Explain what is being done.
  73 .TP
  74 .BR \-V , " \-\-version"
  75 Display version information and exit.
  76 .TP
  77 .BR \-h , " \-\-help"
  78 Display help text and exit.
  79 .SH EXIT STATUS
  80 The
  81 .B mesg
  82 utility exits with one of the following values:
  83 .RS 4
  84 .TP
  85 .B "\ 0"
  86 Messages are allowed.
  87 .TP
  88 .B "\ 1"
  89 Messages are not allowed.
  90 .TP
  91 .B ">1"
  92 An error has occurred.
  93 .RE
  94 .SH FILES
  95 .I /dev/[pt]ty[pq]?
  96 .SH "SEE ALSO"
  97 .BR talk (1),
  98 .BR write (1),
  99 .BR wall (1),
 100 .BR login (1),
 101 .BR xterm (1)
 102 .SH HISTORY
 103 A
 104 .B mesg
 105 command appeared in Version 6 AT&T UNIX.
 106
 107 .SH AVAILABILITY
 108 The mesg command is part of the util-linux package and is available from
 109 ftp://ftp.kernel.org/pub/linux/utils/util-linux/.