terminal-raw mode

[dxs@evolving.com (Dan Stanger)]

has anybody used terminal-raw mode in clisp using the rs6000?
my program is the following
(defun get-field ( stream y-position x-position field-length)
(let ((s (make-string field-length)))
   (screen:set-window-cursor-position stream y-position x-position)
   (system::terminal-raw *keyboard-input* t)
   (do ((i 0)) ((> i field-length))
     (setf (char s i) (read-char *keyboard-input*))
     (break)
     (setf i (+ i 1)))
   (system::terminal-raw *keyboard-input* nil)
   s))
(setf s (screen:make-window))

when i execute (get-field s 10 10 3) the read-char does not terminate
until a carriage return is pressed.  i would like to be able to read
all the keystrokes entered.
thanks,
dan stanger
dxs@evolving.com