WALL(1M)WALL(1M)NAMEwall - write to all users
SYNOPSIS
/etc/wall
DESCRIPTION
Wall reads its standard input until an end-of-file. It then sends this
message, preceded by `Broadcast Message ...', to all logged in users.
The sender should be super-user to override any protections the users
may have invoked.
FILES
/dev/tty?
/etc/utmp
SEE ALSOmesg(1), write(1)DIAGNOSTICS
`Cannot send to ...' when the open on a user's tty file fails.
WALL(1M)