If this_player() is set, send a message "str" to all players in the same object (room) else to all players in the same object (room) as this_object(). This function is also used by the "say" command. If second argument "obj" is specified, messages is sent to all except "obj".

FRIENDLY ADVICE Say uses a lot of magic, only use it if you don't know what you're doing or know exactly what you're doing, tell_room is often preferable.