Revert "socket.recv does not work how I though it did"

This reverts commit 5c03c29b.

TWS/twsproxy/__init__.py

@@ -206,16 +206,10 @@ class TWSProxy(threading.Thread):
                 if msglength > 0:
                     TWSProxy.reliablesend(dest,buff,msglength)
                 if msglength == 0:
-                    """
-                    see https://manpages.debian.org/buster/manpages-dev/recv.2.en.html
-                    in particular
-                    Datagram sockets in various domains (e.g., the UNIX and Internet domains) permit zero-length datagrams. When such a datagram is received, the return value is 0.
-                    """
-                    logger.debug('msglength 0, sending 0 {} {}'.format(src,dest))
-                    dest.send(buff)
-                    #dest.shutdown(shuttype)
-                    #initshutdown.set()
-                    #closed = True
+                    logger.debug('msglength 0, closing {} {}'.format(src,dest))
+                    dest.shutdown(shuttype)
+                    initshutdown.set()
+                    closed = True
 
         logger.debug('ending sock copy {} {}'.format(src,dest))
         dest.shutdown(shuttype)