code: def main(port=4118, parentpid=None):
      
      if "LDTP_DEBUG" in os.environ:
          _ldtp_debug = True
      else:
          _ldtp_debug = False
      _ldtp_debug_file = os.environ.get('LDTP_DEBUG_FILE', None)
      if _ldtp_debug:
          print("Parent PID: {}".format(int(parentpid)))
      if _ldtp_debug_file:
          with open(unicode(_ldtp_debug_file), "a") as fp:
              fp.write("Parent PID: {}".format(int(parentpid)))
      server = LDTPServer(('', port), allow_none=True, logRequests=_ldtp_debug,
                          requestHandler=RequestHandler)
      server.register_introspection_functions()
      server.register_multicall_functions()
      ldtp_inst = core.Core()
      server.register_instance(ldtp_inst)
      if parentpid:
          thread.start_new_thread(notifyclient, (parentpid,))
      try:
          server.serve_forever()
      except KeyboardInterrupt:
          pass
      except:
          if _ldtp_debug:
              print(traceback.format_exc())
          if _ldtp_debug_file:
              with open(_ldtp_debug_file, "a") as fp:
                  fp.write(traceback.format_exc())
docs: Main entry point. Parse command line options and start up a server.