Megatest

	 (handler  (tt-handler ttdat)) ;; the handler comes from our client setting a handler function
	 (handler-proc (lambda ()
			 (let* ((indat         (deserialize))
				(result        #f)
				(exn-result    #f)
				(stdout-result (with-output-to-string
						 (lambda ()
						   (let ((res (handle-exceptions
								  exn
								(let* ((errdat (condition->list exn)))
								  (set! exn-result errdat)
								  (debug:print 0 *default-log-port* "ERROR: handler exception, these are bad, will exit in five seconds.")
								  (pp errdat *default-log-port*)
								  ;; these are always bad, set up an exit thread
								  (thread-start! (make-thread (lambda ()
												(thread-sleep! 5)
												(exit))))
								  #f)
						   (let ((res ;; ndle-exceptions
							      ;;  exn
							      ;; let* ((errdat (condition->list exn)))
							      ;;  (set! exn-result errdat)
							      ;;  (debug:print 0 *default-log-port* "ERROR: handler exception, these are bad, will exit in five seconds.")
							      ;;  (pp errdat *default-log-port*)
							      ;;  ;; these are always bad, set up an exit thread
							      ;;  (thread-start! (make-thread (lambda ()
							      ;; 				(thread-sleep! 5)
							      ;; 				(exit))))
							      ;;  #f)
								(handler indat) ;; this is the proc being called by the remote client
								)))
								)) ;; )
						     (set! result res)))))
				(full-result (list result exn-result (if (equal? stdout-result "") #f stdout-result))))
			   (handle-exceptions
			       exn
			     (begin
			       (debug:print 0 *default-log-port* "Serialization failure. full-result="full-result)
			       ;; (serialize '(#f #f #f)) ;; doesn't work - the first call to serialize caused failure
			   ;; (handle-exceptions
			   ;;     exn
			   ;;   (begin
			   ;;     (debug:print 0 *default-log-port* "Serialization failure. full-result="full-result)
			   ;;     ;; (serialize '(#f #f #f)) ;; doesn't work - the first call to serialize caused failure
			       )
			     (serialize full-result))))))
			   ;;     
			   ;;     )
			     (serialize full-result))))) ;; )
    ((make-tcp-server socket handler-proc)
     #f ;; yes, send error messages to std-err
     )))

;; create a tcp listener and return a populated udat struct with
;; my port, address, hostname, pid etc.
;; return #f if fail to find a port to allocate.