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TCP 4K Write Buffer

Folks,

I'm trying to use mac tcp to communicate between CL-HTTP and a Java
applet. The applet sends me characters OK but when I try to write them
back they seem to get buffered until 4K have been accumulated, then they
get sent. 

I am calling STREAM-FORCE-OUTPUT on the stream. When I inspect the strea
the WRITE-COUNT field goes to zero, but the characters do not get to Java. 

Below is the Lisp code I am using. If anyone can help solve this problem,
I would be grateful.

-Chris Eliot

;;;Tests the ability of Lisp to listen on a socket.
;;;Type (setup-echo-socket nil 123 3) and it will wait for some client to
;;;call up on the given port number, and then it will echo back forms.

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Echo Sockets for Testing ;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

(defvar *java-enable* t)

(defvar *java-communication-processes* nil)

(defvar *java-stream* nil)              ; Last one that talked to me.

(defun java-data-ready (socket)
  (or (listen socket)
      (null *java-enable*)))

(defun echo-socket (host port)
  (let ((socket (open-tcp-stream host port)))
    (unwind-protect
      (loop while (not (stream-eofp socket))
            do (process-wait "JAVA Needed" #'java-data-ready socket)
            do (setq *java-stream* socket)
            if (null *java-enable*) 
            return nil
            do (let ((chr (read-char socket nil :eof)))
                 (if (eq chr #\null)
                   (format t "$")
                   (format t "~c" chr))
                 (write-char chr socket))
            do (stream-force-output socket)
            )
      (stream-close socket))
    ))

(defun setup-echo-sockets (host port count)
  (setq *java-enable* t)
  (loop for i from 1 to count
        for process = (process-run-function
                       (format nil "JAVA SOCKET ~s" i)
                       #'echo-socket  host port)
        ;; Make a list of the processes, so that we can later check on
        ;; them to determine if they are still alive. Currently, I am
        ;; not sure what is the best way to do that check.
        do (push process *java-communication-processes*)))

(defun close-echo-sockets ()
  (setq *java-enable* nil))

(setup-echo-sockets nil 123 3)


Christopher R. Eliot, Senior Postdoctoral Research Associate
Center for Knowledge Communication, Department of Computer Science
University of Massachusetts, Amherst. (413) 545-4248 FAX: 545-1249
ELIOT@cs.umass.edu,   http://rastelli.cs.umass.edu/~ckc/people/eliot/