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.
-g
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.
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).
History
FreeBSD 16.0-CURRENT (2026-10-27) to FreeBSD 15.0-RELEASE: the text shown here
