Megatest

(define (send-via-mailbox uconn host-port cmd data)
  (let* ((cmbox     (get-cmbox uconn)) ;; would it be better to keep a stack of mboxes to reuse?
	 (qrykey    (car cmbox))
	 (mbox      (cdr cmbox))
	 (mbox-time (current-milliseconds))
	 (sres      (send uconn host-port qrykey cmd data))) ;; short res
    (if (eq? sres 'ack) ;; BUG: change to be less than server:expiration-timeout?
	(let* ((mbox-timeout-secs    120 #;(if (eq? 'primordial (thread-name (current-thread)))
				     #f
				     120)) ;; timeout)
	       (mbox-timeout-result 'MBOX_TIMEOUT)
	       (res                  (mailbox-receive! mbox mbox-timeout-secs mbox-timeout-result))
	       (mbox-receive-time    (current-milliseconds)))
	  ;; (put-cmbox uconn cmbox) ;; reuse mbox and cookie. is it worth it?

	      (run-time (- end-time start-time)))
	 (case (work-method)
	   ((direct) result)
	   (else
	    (print "ULEX: work "cmd", "params" done in "run-time" ms")
	    ;; send 'response as cmd and result as params
	    (send uconn rem-host-port qrykey 'response result) ;; could check for ack
	    (print "ULEX: response sent back to "rem-host-port" for "qrykey" in "(- (current-milliseconds) end-time)"ms")))))
      (MBOX_TIMEOUT 'do-work-timeout)
      (else
       (print "ERROR: rdat "rdat", did not match rem-host-port qrykey cmd params")))))

;; NEW APPROACH:
;;   
(define (process-work-queue uconn)