ADDED   testzmq/mockupclient.scm
Index: testzmq/mockupclient.scm
==================================================================
--- /dev/null
+++ testzmq/mockupclient.scm
@@ -0,0 +1,30 @@
+(use zmq)
+
+(define cname "Bob")
+(let ((args (argv)))
+  (if (< (length args) 3)
+      (begin
+	(print "Usage: mockupclient clientname")
+	(exit))
+      (set! cname (cadr args))))
+      
+(define sub  (make-socket 'sub))
+(define push (make-socket 'push))
+(socket-option-set! sub 'subscribe cname)
+(connect-socket sub "tcp://localhost:5563")
+(connect-socket push "tcp://localhost:5564")
+
+(define (dbaccess cmd var val)
+  (let ((msg (conc cname ":" cmd ":" (if val (conc var " " val) var))))
+    (print "Sending msg: " msg)
+    (send-message push msg)
+    (receive-message* sub)))
+
+(let loop ()
+  (case (random 5)
+    ((1)(dbaccess sync "" #f))
+    (else
+     (thread-sleep! 1)))
+  (loop))
+
+

ADDED   testzmq/mockupserver.scm
Index: testzmq/mockupserver.scm
==================================================================
--- /dev/null
+++ testzmq/mockupserver.scm
@@ -0,0 +1,93 @@
+;; pub/sub with envelope address
+;; Note that if you don't insert a sleep, the server will crash with SIGPIPE as soon
+;; as a client disconnects.  Also a remaining client may receive tons of
+;; messages afterward.
+
+(use zmq srfi-18 sqlite3)
+
+(define pub (make-socket 'pub))
+(define pull (make-socket 'pull))
+
+(bind-socket pub "tcp://*:5563")
+(bind-socket pull "tcp://*:5564")
+
+(define (open-db)
+  (let* ((dbpath    "mockupserver.db")
+	 (dbexists  (file-exists? dbpath))
+	 (db        (open-database dbpath)) ;; (never-give-up-open-db dbpath))
+	 (handler   (make-busy-timeout 10)))
+    (set-busy-handler! db handler)
+    (if (not dbexists)
+	(for-each
+	 (lambda (stmt)
+	   (execute db stmt))
+	 (list
+	  "CREATE TABLE clients (id INTEGER PRIMARY KEY,name TEXT,num_accesses INTEGER);"
+	  "CREATE TABLE vars    (var TEXT,val TEXT,CONSTRAINT vars_constraint UNIQUE (var));")))
+    db))
+
+(define db (open-db))
+;; (define queuelst '())
+;; (define mx1 (make-mutex))
+
+(define (process-queue queuelst)
+  (for-each
+   (lambda (item)
+     (let ((cname (vector-ref item 1))
+	   (clcmd (vector-ref item 2))
+	   (cdata (vector-ref item 3)))
+       (send-message pub cname send-more: #t)
+       (send-message pub (case clcmd
+			   ((setval)
+			    (apply execute db "INSERT OR REPLACE INTO vars (var,val) VALUES (?,?);" (string-split cdata))
+			    "ok")
+			   ((getval)
+			    (let ((res "noval"))
+			      (for-each-row
+			       (lambda (val)
+				 (set! res val))
+			       db 
+			       "SELECT val FROM vars WHERE var=?;" cdata)
+			      res))
+			   (else (conc "unk cmd: " clcmd))))))
+   queuelst))
+
+(define th1 (make-thread 
+	     (lambda ()
+	       (let ((last-run 0)) ;; current-seconds when run last
+		 (let loop ((queuelst '()))
+		   (let* ((indat (receive-message* pull))
+			  (parts (string-split indat ":"))
+			  (cname (car parts))                   ;; client name
+			  (clcmd (string->symbol (cadr parts))) ;; client cmd
+			  (cdata (caddr parts))                 ;; client data
+			  (svect (vector (current-seconds) cname clcmd cdata))) ;; record for the queue
+		     ;; (print "Got indat=" indat)
+		     (case clcmd
+		       ((sync) ;; just process the queue
+			(print "Got sync from " cname)
+			(process-queue queuelst)
+			(loop '()))
+		       ((imediate)
+			(process-queue (cons svect queuelst))
+			(loop '()))
+		       (else
+			(loop (cons svect queuelst))))))))
+	     "server thread"))
+
+(define push (make-socket 'push))
+(connect-socket push "tcp://localhost:5564")
+
+;; send a sync to the pull port
+(define th2 (make-thread
+	     (lambda ()
+	       (let loop ()
+		 (thread-sleep! 3)
+		 ;; (print "Sending sync from server")
+		 (send-message push "server:sync:nodat")
+		 (loop)))
+	     "sync thread"))
+
+(thread-start! th1)
+(thread-start! th2)
+(thread-join! th1)

ADDED   testzmq/testmockup.sh
Index: testzmq/testmockup.sh
==================================================================
--- /dev/null
+++ testzmq/testmockup.sh
@@ -0,0 +1,10 @@
+#!/bin/bash
+
+csc mockupserver.scm
+csc mockupclient.scm
+
+./mockupserver &
+
+for i in a b;do
+  ./mockupclient $i &
+done