Fourth,you have to be particularly careful with the INVALID_HANDLE_VALUE value: By coincidence,the value INVALID_HANDLE_VALUE happens to be numerically equal to the pseudohandle returned by GetCurrentProcess(). Many kernel functions accept pseudohandles,so if if you mess up and accidentally call,say,WaitForSingleObject on a Failed INVALID_HANDLE_VALUE handle,you will actually end up waiting on your own process. This wait will,of course,never complete,because a process is signalled when it exits,so you ended up waiting for yourself.