add example using select/asyncore from http://etutorials.org/Programming/Python+tutorial/Part+IV+Network+and+Web+Programming/Chapter+19.+Sockets+and+Server-Side+Network+Protocol+Modules/19.3+Event-Driven+Socket+Programs/

select/TcpServer.py

@@ -0,0 +1,58 @@
+import socket
+import select
+sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+sock.bind(('', 8881))
+sock.listen(5)
+
+# lists of sockets to watch for input and output events
+ins = [sock]
+ous = []
+# mapping socket -> data to send on that socket when feasible
+data = {}
+# mapping socket -> (host, port) on which the client is running
+adrs = {}
+
+try:
+    while True:
+        i, o, e = select.select(ins, ous, [])  # no excepts nor timeout
+        for x in i:
+            if x is sock:
+                # input event on sock means client trying to connect
+                newSocket, address = sock.accept(  )
+                print "Connected from", address
+                ins.append(newSocket)
+                adrs[newSocket] = address
+            else:
+                # other input events mean data arrived, or disconnections
+                newdata = x.recv(8192)
+                if newdata:
+                    # data arrived, prepare and queue the response to it
+                    print "%d bytes from %s" % (len(newdata), adrs[x])
+                    data[x] = data.get(x, '') + newdata
+                    if x not in ous: ous.append(x)
+                else:
+                    # a disconnect, give a message and clean up
+                    print "disconnected from", adrs[x]
+                    del adrs[x]
+                    try: ous.remove(x)
+                    except ValueError: pass
+                    x.close(  )
+        for x in o:
+            # output events always mean we can send some data
+            tosend = data.get(x)
+            if tosend:
+                nsent = x.send(tosend)
+                print "%d bytes to %s" % (nsent, adrs[x])
+                # remember data still to be sent, if any
+                tosend = tosend[nsent:]
+            if tosend: 
+                print "%d bytes remain for %s" % (len(tosend), adrs[x])
+                data[x] = tosend
+            else:
+                try: del data[x]
+                except KeyError: pass
+                ous.remove(x)
+                print "No data currently remain for", adrs[x]
+finally:
+    sock.close(  )
+