prasad_som wrote: I'll use CWnd::PostMessage, if I've CWnd object(no need to wrap window handle, specially to use this version), and ::PostMessage, if I've window handle. So you'll use both at the same time when you have a CWnd object... :rolleyes: Pardon the silly humour... If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile. This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke [My articles]

Many thanks for help given, I now have a basic 'thread' the compiles and does roughly what I expect :)

Easy one first: GC104 wrote: Sprintf(BasicString, "ABCDDEF") : Bad because I haven't initialised it as soon as I declared it? or the fact that I'm using sprintf to load the string? Bad because it wasn't char BasicString[100]; when I answered the question - it was (IIRC) char* BasicString :-) Also - sprintf is less than optimal for assigning a string to another string - strcpy is better, I guess. GC104 wrote: Any suggestions for an alternative to CW2A macro? CW2A isn't a macro. It's a class. There are a few alternatives: Make sure that pOutputString has storage associated with it and strcpy the CW2A into it: char pOutputString\[1024\]; strcpy(pOutputString, CW2A(TxString)); Declare pOutputString to be of type CW2A and assign TXString to it. THat way the storage is associated with the lifetime of pOutputString, which is what you want: CW2A pOutputString = TxString; Declare pOutputString to be of some other ASCII string type and assign CW2A(TXString) to it. That way there is storage associated with the lifetime of pOutputString, which is what you want: std::string pOutputString = CW2A(TxString); I'd go for option 2, personally. Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Hi all, Thanks for responses. It looks like CPallini nailed it - the compiler doing its job! I have since added more data members to capture the results of the various functions I used on the original code. However this time, the debugger runs through eacdh line and loads each variable with the value I was expected many thanks Geoff :)

Sorry, I made a typo whilst trying 'attempt 1'. Yolu're right it does compile, the problem is that pActualBytesRead gets loaded with 0xbaadf00d prior to the 'ReadFile' call. Thanks for help :)