[640] inline comment

src/bin/cmdctl/cmdctl.py.in

@@ -310,6 +310,10 @@ class CommandControl():
     def command_handler(self, command, args):
         answer = ccsession.create_answer(0)
         if command == ccsession.COMMAND_MODULE_SPECIFICATION_UPDATE:
+            # The 'value' of a specification update can be either
+            # a specification, or None. In the first case, simply
+            # set it. If it is None, delete the module if it is
+            # known (and ignore otherwise).
             with self._lock:
                 if args[1] is None and args[0] in self.modules_spec:
                     del self.modules_spec[args[0]]