Команда mesg
Lets you control if people can use the write command, to send text to you over the screen.
mesg [n|y]
| n | Prevents the messages from others popping up on your screen. |
| y | Allows messages to appear on your screen. |
mesg
Typing this command by itself will display whether or not the mesg service is enabled. For example, it may display: "is y", indicating that it is enabled. Typing n or why after the command would enable or disable this command.
When this command is disabled non-root users will be unable to to send messages to you using message commands such as talk or write.