Your situation is not about where the error device is outputting to, but it's exactly about whether your code has an intention to write to it. Whatever the device really is, if you don't need to...
I would dare to disagree. :) It highly depends on the way how you design data types and interfaces. Please consider the plain C sample (monolithic, not a LIB or DLL) attached.
Man, it seems you don't listen. Not any code can be unit tested. If you can't mock the type you have to mock, you either change your code or switch to a smarter unit test framework.
Good questions, and I believe all of them should be directed to MS. :) What I said is just my in-mind how-it-would-be construct based on my many years of programming Windows, and I never saw this...
I don't get what you talk about. You test only what you test, you mock everything else. The framework you use ideally helps you to generate mocked interfaces. If it does not, you either find another...
The PSN_SETACTIVE is sent by Property Sheet control. It seems the control re-sends the message in case it considers the previous message lost due to some reason. The lengthy operation (or Sleep) you...
To be sure the program is running as instructed you have to analyze your requirements and make a plan how you make sure not only about normal cases but error cases/input as well. Please don't get me...
Edit Control Notifications do not include double click event. To catch one you have to subclass the control and provide your custom handler for WM_LBUTTONDBLCLK message.
CFileDialog is just a thin wrapper over GetOpenFileName. What's the problem to write a function that suits your needs? You do this every single day, don't you? :confused: