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MESG(1)				 User Commands			       MESG(1)

NAME
       mesg - display (or do not display) messages from	other users

SYNOPSIS
       mesg [option] [n|y]

DESCRIPTION
       The mesg	utility	is invoked by a	user to	control	write access others
       have to the terminal device associated with standard error output. If
       write access is allowed,	then programs such as talk(1) and write(1) may
       display messages	on the terminal.

       Traditionally, write access is allowed by default. However, as users
       become more conscious of	various	security risks,	there is a trend to
       remove write access by default, at least	for the	primary	login shell.

       The initial permissions for the terminal	are set	by login(1) according
       to TTYPERM and TTYGROUP from /etc/login.defs. The default is mode 0620
       if a tty	group is used, and 0600	without	the group. The default tty
       group name is "tty".

       To ensure that your ttys	are set	in a portable and independent manner
       from system settings, mesg should be executed in	your login scripts.

       mesg modifies the write permissions for a group on the current terminal
       device. Since version 2.41, mesg	can no longer be compiled to make the
       terminal	writable for others and	strictly modifies only group
       permissions. The	usual setup is to use a	"tty" group and	add relevant
       users to	this group. Alternatively, a less secure solution is to	set
       utilities like write(1) or wall(1) to setgid for	the "tty" group.

       The mesg	utility	silently exits with error status 2 if not executed on
       a terminal. In this case	executing mesg is pointless. The command line
       option --verbose	forces mesg to print a warning in this situation. This
       behaviour has been introduced in	version	2.33.

ARGUMENTS
       n
	   Disallow messages.

       y
	   Allow messages to be	displayed.

       If no arguments are given, mesg shows the current message status	on
       standard	error output.

OPTIONS
       -v, --verbose
	   Explain what	is being done.

       -h, --help
	   Display help	text and exit.

       -V, --version
	   Display version and exit.

EXIT STATUS
       The mesg	utility	exits with one of the following	values:

       0
	   Messages are	allowed.

       1
	   Messages are	not allowed.

       >1
	   An error has	occurred.

FILES
       /dev/[pt]ty*, /dev/pts/[0-9]*

HISTORY
       mesg (I)	appears	in the UNIX Programmer's Manual. It used to invert the
       current state with no argument before Version 7 AT&T UNIX.

SEE ALSO
       login(1), talk(1), write(1), wall(1), xterm(1)

REPORTING BUGS
       For bug reports,	use the	issue tracker
       <https://github.com/util-linux/util-linux/issues>.

AVAILABILITY
       The mesg	command	is part	of the util-linux package which	can be
       downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>.

util-linux 2.41.2		  2025-09-22			       MESG(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=mesg&sektion=1&manpath=FreeBSD+Ports+15.0>

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