[WPI] interj. 1. An indication of confusion, usually spoken
with a quizzical tone "Wall??" 2. A request for further
explication. Compare octal forty
. 3. [UNIX] v. To send a message
to everyone currently logged in, esp. with the wall(8) utility.
It is said that sense 1 came from the idiom `like talking to a
blank wall'. It was originally used in situations where, after you
had carefully answered a question, the questioner stared at you
blankly, clearly having understood nothing that was explained. You
would then throw out a "Hello, wall?" to elicit some sort of
response from the questioner. Later, confused questioners began
voicing "Wall?" themselves.