ADDED   ulex/Makefile
Index: ulex/Makefile
==================================================================
--- /dev/null
+++ ulex/Makefile
@@ -0,0 +1,9 @@
+all : ulex.pdf ulex.png
+
+ulex.pdf : ulex.dot
+	dot -Tpdf ulex.dot -o ulex.pdf
+
+ulex.png : ulex.dot
+	dot -Tpng ulex.dot -o ulex.png
+
+

ADDED   ulex/ulex.dot
Index: ulex/ulex.dot
==================================================================
--- /dev/null
+++ ulex/ulex.dot
@@ -0,0 +1,136 @@
+//  Copyright 2006-2017, Matthew Welland.
+// 
+// This file is part of Megatest.
+// 
+//     Megatest is free software: you can redistribute it and/or modify
+//     it under the terms of the GNU General Public License as published by
+//     the Free Software Foundation, either version 3 of the License, or
+//     (at your option) any later version.
+// 
+//     Megatest is distributed in the hope that it will be useful,
+//     but WITHOUT ANY WARRANTY; without even the implied warranty of
+//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//     GNU General Public License for more details.
+// 
+//     You should have received a copy of the GNU General Public License
+//     along with Megatest.  If not, see <http://www.gnu.org/licenses/>.
+
+digraph G {
+
+  // graph[center=true, margin=0.2, nodesep=0.1, ranksep=0.3]
+
+  layout=neato;
+  // layout=fdp;
+  // overlap=scalexy; //false, compress, ...
+  overlap=scalexy;
+  // sep="+1"; // 0.1, +1
+  sep="-0.1";
+ 
+  user_program [label="user program"];
+  
+  subgraph cluster_1 {
+    node [style=filled,shape=oval];
+    label = "caller";
+    color=brown;
+
+    send_receive [label="(send-receive uconn\n   host-port qrykey cmd data)"];
+    send [label="(send uconn host-port\n    qrykey cmd data)"];
+    ulex_cmd_loopcaller [label="(ulex-cmd-loop uconn)"];
+    ulex_handlercaller [label="(ulex-handler uconn rdat)"];
+    mailbox [label="mailbox\n\nrdat\n...",shape=box];
+    
+    send_receive -> send;
+    ulex_cmd_loopcaller -> ulex_handlercaller;
+    ulex_handlercaller -> mailbox;
+    mailbox -> send_receive;
+  }
+
+  subgraph cluster_2 {
+    node [shape=oval];
+    label = "listener";
+    color=green;
+
+    ulex_cmd_loop [label="(ulex-cmd-loop uconn)"];
+    ulex_handler [label="(ulex-handler \nuconn rdat)"];
+    add_to_work_queue [label="(add-to-work-queue\n  uconn rdat)"];
+    queue [label="queue\n\nrdat\n...",shape=box];
+    process_work_queue [label="(process-work-queue uconn)"];
+    do_work [label="(do-work uconn rdat)\nrdat: '(rem-host-port qrykey cmd params)"];
+    user_proc [label="(proc rem-host-port\n    qrykey cmd params)\n;; proc supplied by user"];
+    sendlis [label="(send uconn host-port\n    qrykey 'response result)"];
+    
+    ulex_cmd_loop -> ulex_handler [label="rdat"];
+    ulex_handler -> add_to_work_queue [label="rdat"];
+
+    add_to_work_queue -> queue [label="rdat"];
+
+    subgraph cluster_3 {
+      label = "remote work";
+      color=blue;
+      
+      queue -> process_work_queue [label="rdat"];
+      process_work_queue -> do_work [label="rdat"];
+      do_work -> user_proc; // [label="rdat: '(rem-host-port\n   qrykey cmd params)"];
+    }
+  }
+
+  user_proc -> sendlis;
+  user_program -> send_receive;
+  send_receive -> user_program;
+  
+  send -> ulex_cmd_loop [label="rdat: '(host-port\n  qrykey cmd data)"];
+  sendlis -> ulex_cmd_loopcaller [label="rdat: '(host-port qrykey\n  'response result)"];
+  ulex_handler -> send [label="'ack"];
+  ulex_handlercaller -> sendlis [label="'ack"];
+  
+}
+
+
+// 	check_available_queue       -> remove_entries_over_10s_old;
+// 	remove_entries_over_10s_old -> set_available [label="num_avail < 3"];
+// 	remove_entries_over_10s_old -> exit [label="num_avail > 2"];
+// 
+// 	set_available               -> delay_2s;
+// 	delay_2s          -> check_place_in_queue;
+// 
+// 	check_place_in_queue        -> "http:transport-launch" [label="at head"];
+// 	check_place_in_queue        -> exit [label="not at head"];
+// 
+// 	"client:login"              -> "server:shutdown" [label="login failed"];
+// 	"server:shutdown"           -> exit;	
+// 
+// 	subgraph cluster_2 {
+// 		"http:transport-launch"       -> "http:transport-run";
+// 		"http:transport-launch"       -> "http:transport-keep-running";
+// 
+// 		"http:transport-keep-running" -> "tests running?";
+// 		"tests running?"              -> "client:login" [label=yes];
+// 		"tests running?"              -> "server:shutdown" [label=no];
+// 		"client:login"                -> delay_5s [label="login ok"];
+// 		delay_5s                      -> "http:transport-keep-running";
+// 	}
+// 
+	// start_server -> "server_running?";
+	// "server_running?" -> set_available [label="no"];
+	// "server_running?" -> delay_2s [label="yes"];
+	// delay_2s -> "still_running?";
+	// "still_running?" -> ping_server [label=yes];
+	// "still_running?" -> set_available [label=no];
+	// ping_server -> exit [label=alive];
+	// ping_server -> remove_server_record [label=dead];
+	// remove_server_record -> set_available;
+	// set_available -> avail_delay [label="delay 3s"];
+	// avail_delay -> "first_in_queue?";
+	// 
+	// "first_in_queue?" -> set_running [label=yes];
+	// set_running -> get_next_port -> handle_requests;
+	// "first_in_queue?" -> "dead_entry_in_queue?" [label=no];
+	// "dead_entry_in_queue?" -> "server_running?" [label=no];
+	// "dead_entry_in_queue?" -> "remove_dead_entries" [label=yes];
+	// remove_dead_entries -> "server_running?";
+	// 
+	// handle_requests -> start_shutdown [label="no traffic\nno running tests"];
+	// handle_requests -> shutdown_request;
+	// start_shutdown -> shutdown_delay;
+	// shutdown_request -> shutdown_delay;
+	// shutdown_delay -> exit;

ADDED   ulex/ulex.pdf
Index: ulex/ulex.pdf
==================================================================
--- /dev/null
+++ ulex/ulex.pdf
cannot compute difference between binary files

ADDED   ulex/ulex.png
Index: ulex/ulex.png
==================================================================
--- /dev/null
+++ ulex/ulex.png
cannot compute difference between binary files

Index: ulex/ulex.scm
==================================================================
--- ulex/ulex.scm
+++ ulex/ulex.scm
@@ -230,28 +230,28 @@
 
 ;;======================================================================
 ;; responder side
 ;;======================================================================
 
-;; take a request, rdata, and if not immediate put it in the work queue
+;; take a request, rdat, and if not immediate put it in the work queue
 ;;
 ;; Reserved cmds; ack ping goodbye response
 ;;
-(define (ulex-handler uconn rdata)
-  (match rdata ;;  (string-split controldat)
+(define (ulex-handler uconn rdat)
+  (match rdat ;;  (string-split controldat)
     ((rem-host-port qrykey cmd params)
      ;; (print "ulex-handler got: "rem-host-port" qrykey: "qrykey" cmd: "cmd" params: "params)
      (let ((mbox (hash-table-ref/default (udat-mboxes uconn) qrykey #f)))
        (case cmd
 	 ;; ((ack )(print "Got ack! But why? Should NOT get here.") 'ack)
 	 ((ping)
 	  ;; (print "Got Ping!")
-	  (add-to-work-queue uconn rdata)
+	  (add-to-work-queue uconn rdat)
 	 'ack)
 	 ((goodbye)
 	  ;; just clear out references to the caller
-	  (add-to-work-queue uconn rdata)
+	  (add-to-work-queue uconn rdat)
 	  'ack)
 	 ((response) ;; this is a result from remote processing, send it as mail ...
 	  (if mbox
 	      (begin
 		(mailbox-send! mbox params) ;; params here is our result
@@ -259,24 +259,24 @@
 	      (begin
 		(print "ERROR: received result but no associated mbox for cookie "qrykey)
 		#f)))
 	 (else
 	  ;; (print "Got generic request: "cmd)
-	  (add-to-work-queue uconn rdata)
+	  (add-to-work-queue uconn rdat)
 	  'ack))))
     (else
-     (print "BAD DATA? controldat=" rdata)
+     (print "BAD DATA? controldat=" rdat)
      'ack) ;; send ack anyway?
     ))
 
 ;; given an already set up uconn start the cmd-loop
 ;;
 (define (ulex-cmd-loop uconn)
   (let* ((serv-listener (udat-socket uconn)))
     (let loop ((state 'start))
       (let-values (((inp oup)(tcp-accept serv-listener)))
-	(let* ((rdat  (read inp))
+	(let* ((rdat  (read inp)) ;; '(my-host-port qrykey cmd params)
 	       (resp  (ulex-handler uconn rdat)))
 	  (if resp (write resp oup))
 	  (close-input-port inp)
 	  (close-output-port oup))
 	(loop state)))))
@@ -289,35 +289,35 @@
 
 ;;======================================================================
 ;; work queues - this is all happening on the listener side
 ;;======================================================================
 
-;; rdata is (rem-host-port qrykey cmd params)
+;; rdat is (rem-host-port qrykey cmd params)
 					     
-(define (add-to-work-queue uconn rdata)
-  (queue-add! (udat-work-queue uconn) rdata))
+(define (add-to-work-queue uconn rdat)
+  (queue-add! (udat-work-queue uconn) rdat))
 
-(define (do-work uconn rdata)
+(define (do-work uconn rdat)
   (let* ((proc (udat-work-proc uconn))) ;; get it each time - conceivebly it could change
     ;; put this following into a do-work procedure
-    (match rdata
+    (match rdat
       ((rem-host-port qrykey cmd params)
        (let* ((result (proc rem-host-port qrykey cmd params)))
 	 ;; send 'response as cmd and result as params
 	 (send uconn rem-host-port qrykey 'response result))) ;; could check for ack
       (else
-       (print "ERROR: rdata "rdata", did not match rem-host-port qrykey cmd params")))))
+       (print "ERROR: rdat "rdat", did not match rem-host-port qrykey cmd params")))))
      
      
 (define (process-work-queue uconn) 
   (let ((wqueue (udat-work-queue uconn))
 	(proc   (udat-work-proc  uconn)))
     (let loop ()
       (if (queue-empty? wqueue)
 	  (thread-sleep! 0.1)
-	  (let ((rdata (queue-remove! wqueue)))
-	    (do-work uconn rdata)))
+	  (let ((rdat (queue-remove! wqueue)))
+	    (do-work uconn rdat)))
       (loop))))
 
 ;; below was to enable re-use of connections. This seems non-trivial so for
 ;; now lets open on each call
 ;;