Francois PIETTE schrieb: > As expressed in the source code, ReadLine is deprecated. Anyway, it doesn't > fit correctly with UDP protocol which is datagram oriented. Using "lines" > with such protocol is strange. > > >>Now I have the problem that at one place in the program I need >>synchronus communication. I send out one byte and if I receive the same >>byte within some short timeout, I assume that the device I'm talking to >>has a echo mode. > > > Send your byte then program a loop waiting for the evnt OnDataAvailable to > occur before a given time. Not the best practice, but that's how you can > implement synchronous operation if you really need this (you can ALWAYS > avoid synchronous operation). > > When you are in your wait loop, you must process events or your application > will be locked. You must do something like that (not checked, out of my > head) : > > FReceiveFlag := FALSE; > WSocket1.Send(...your one byte data ....); > while not FReceiveFlag do begin > DummyHandle := INVALID_HANDLE_VALUE; > MsgWaitForMultipleObjects(0, DummyHandle, FALSE, 1000, > QS_ALLINPUT + QS_ALLEVENTS + > QS_KEY + QS_MOUSE); > Application.ProcessMessages; > if Application.Terminated then > break; > end; > > OnDataAvailable handler will set the FReceiveFlag variable to TRUE. > You can also use a TTimer to check for timeout. > Thanks for the reply, I will consider that tomorrow. Normally I do asynchronos communication, but for the first test wether my communication partner has echo or not I don't want this, I simply want this one synchronous.
The thing is that the code is in a dll, so application.processmessages might not work here. Or does it? The timeout will be rather short anyhow (ca. 50 ms) and I think i do it with GetTickCount, which should be sufficient here and more easy to use than a at this place timer. Or is there anything bad with these ideas? Greetings Markus Humm -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
