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diff --git a/Demo/sgi/video/vtime.py b/Demo/sgi/video/vtime.py
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+#
+# Module vtime - Keep virtual time between two nodes.
+#
+# We try for synchronised clocks by sending a packet of the for
+# (1,mytime,0) to the other side, and waiting (at most) a second for
+# a reply. This reply has the form (2,mytime,histime), and we can
+# estimate the time difference by defining histime to be exactly half-way
+# between the time we sent our message and got our reply. We send a
+# final (3,mynewtime,histime) message to allow the other side to do the
+# same computations.
+#
+# Note that the protocol suffers heavily from the 2-army problem.
+# It'll have to do until I can read up on time-sync protocols, though.
+#
+from socket import *
+import time
+
+MSGSIZE = 100
+MSGTIMEOUT = 1000
+
+recv_timeout = 'receive timeout'
+bad_connect = 'Bad connection'
+
+def timeavg(a,b):
+    return int((long(a)+b)/2L)
+def tryrecv(s):
+    cnt = 0
+    while 1:
+	if s.avail():
+	    return s.recvfrom(MSGSIZE)
+	time.millisleep(100)
+	cnt = cnt + 100
+	if cnt > MSGTIMEOUT:
+	    raise recv_timeout
+
+class VTime():
+    def init(self,(client,host,port)):
+	s = socket(AF_INET, SOCK_DGRAM)
+	host = gethostbyname(host)
+	localhost = gethostbyname(gethostname())
+	raddr = (host,port)
+	s.bind((localhost,port))
+	if client:
+	    #
+	    # We loop here because we want the *second* measurement
+	    # for accuracy
+	    for loopct in (0,2):
+		curtijd = time.millitimer()
+		check = `(loopct,curtijd,0)`
+		s.sendto(check,raddr)
+		while 1:
+		    try:
+			if loopct:
+			    data, other = s.recvfrom(MSGSIZE)
+			else:
+			    data, other = tryrecv(s)
+			newtijd = time.millitimer()
+			if other <> raddr:
+			    print 'Someone else syncing to us: ', other
+			    raise bad_connect
+			data = eval(data)
+			if data[:2] = (loopct+1,curtijd):
+			    break
+			if data[0] <> 2:
+			    print 'Illegal sync reply: ', data
+			    raise bad_connect
+		    except recv_timeout:
+			curtijd = time.millitimer()
+			check = `(loopct,curtijd,0)`
+			s.sendto(check,raddr)
+	    histime = data[2]
+	    s.sendto(`(4,newtijd,histime)`,raddr)
+	    mytime = timeavg(curtijd,newtijd)
+	    #mytime = curtijd
+	    self.timediff = histime - mytime
+	else:
+	    while 1:
+		data,other = s.recvfrom(MSGSIZE)
+		if other <> raddr:
+		    print 'Someone else syncing to us: ', other, ' Wanted ', raddr
+		    raise bad_connect
+		data = eval(data)
+		if data[0] in (0,2):
+		    curtijd = time.millitimer()
+		    s.sendto(`(data[0]+1,data[1],curtijd)`,raddr)
+		elif data[0] = 4:
+		    newtijd = time.millitimer()
+		    histime = data[1]
+		    mytime = timeavg(curtijd,newtijd)
+		    #mytime = curtijd
+		    self.timediff = histime-mytime
+		    break
+		else:
+		    print 'Funny data: ', data
+		    raise bad_connect
+	return self
+	#
+    def his2mine(self,tijd):
+	return tijd - self.timediff
+    #
+    def mine2his(self, tijd):
+	return tijd + self.timediff
+
+def test(clt, host, port):
+    xx = VTime().init(clt,host,port)
+    print 'Time diff: ', xx.his2mine(0)