NAME

wall  −  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 superuser to override any protections the users may have invoked. 

FILES

/dev/tty? 
/etc/utmp

SEE ALSO

mesg(1), write(1)

DIAGNOSTICS

´Cannot send to ...’ when the open on a user’s tty file fails.