(an abbreviation of write to all) is a Unix command-line utility that displays the contents of a computer file or standard input to all logged-in users. It is typically used by root to send out shutting down message to all users just before poweroff.
reads the message from standard input by default when the filename is omitted. This is done by piping the output of the command:
The message may also be typed in much the same way is used: invoking by typing and pressing followed by a message, pressing and +:
Using a here-string:
Reading from a file is also supported:
All the commands above should display the following output on terminals that users allow write access to (see [[mesg]](1)
):
Remember to brush your teeth!