Why Reading Memory Could be Detected

[BruceCopperField]

I've read some old posts about memory reading in WoW and the risk of being caught by Warden. I am not writing a bot for Wow. Actually, I dont play this game at all. But I am interested in learning windows system programming. From what I understand, the UDFs for reading memory just make a Win32 call to Windows to dump the memory of another process. However, would a process know its memory is being read? Afterall, Windows should (pls correct me if not) shield this action from the process itself. In that case, how could Warden knows a bot is doing memory reading?

[Richard Robertson]

Many anti-hack engines will watch calls to certain functions. It's possible by attaching to all open processes and modifying the stacks a bit. I don't know the technical details, but it's the same idea that gets applied to when a programmer gets the painting of a hidden window.