message loop for --gui-exe compiled code?

[Jong-Kyou Kim <jkkim@chollian.net>]

I wrote and compiled the following code using `mzc --gui-exe'. The
program, however, didn't wait any input. It terminated immediately.

<<<<
(define frame (make-object frame% "example"))
(send frame show #t)
(define msg (make-object message% "No event" frame))
(make-object button% "btn" frame
      (lambda (button event)
        (send msg set-label "btn click")))
(make-object button% "exit" frame
      (lambda (button event)
        (exit)))
>>>>

So I added the following code:

<<<<
(thread (let loop () (sleep 0.03) (yield) (loop)))
>>>>

Though it worked for my small project, I think there must be better way
to do this. If anybody know how to do it, please let me know it.

Thanks in advance

Jong-kyou