WinHLLAPISetBlockingHook

This function sets an application-defined procedure to be executed while waiting for the completion of a blocking call. A blocking call is any synchronous function that takes a long time to execute and does not return until complete. There are five blocking calls in this implementation of WinHLLAPI. The blocking calls are: Get Key (51), Wait (4), Pause (18), Send File (90), and Receive File (91).