Wait for credit before closing the connection.

os2-tcp-test-date-service.rkt

@@ -10,11 +10,13 @@
 (define ((connection-handler local-addr remote-addr) self-pid)
   (transition 'no-state
     (role 'date-sender (topic-publisher (tcp-channel local-addr remote-addr (wild)))
-      #:state state)
+      #:state state
+      [(tcp-channel _ _ (tcp-credit _))
+       (transition state
+	 (kill))])
     (send-message (tcp-channel local-addr remote-addr
 			       (string->bytes/utf-8
-				(format "~a\n" (current-inexact-milliseconds)))))
-    (kill)))
+				(format "~a\n" (current-inexact-milliseconds)))))))
 
 (define (listener local-addr)
   (transition 'no-state