MESG(1) MESG(1) mesg - ( ) mesg [] [n|y] mesg , ' . , , talk(1) write(1), . , . , , ' , ' , . 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. mesg 2, . mesg . --verbose mesg . 2.33. n . y . , mesg . -v, --verbose . -h, --help . -V, --version . mesg : 0 . 1 . >1 . /dev/[pt]ty*, /dev/pts/[0-9]* 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. login(1), talk(1), write(1), wall(1), xterm(1) mesg util-linux, Linux . util-linux 2.41 2025-03-29 MESG(1)