WALL(1) General Commands Manual WALL(1)

wall — write a message to users

wall [-g group] [file]

The wall utility displays the contents of file or, by default, its standard input, on the terminals of all currently logged in users.

Only the super-user can write on the terminals of users who have chosen to deny messages or are using a program which automatically denies messages.

Send messages to users in this group. This option may be specified multiple times, and any user in any of the specified groups will receive the message.

mesg(1), talk(1), write(1), shutdown(8)

A wall command appeared in PWB UNIX.

The sender's LC_CTYPE setting is used to determine which characters are safe to write to a terminal, not the receiver's (which wall has no way of knowing).

February 24, 2012 macOS 15.2