Provides a high performance test operation that can be used to poll for the completion of an outstanding I/O operation.
A pointer to an OVERLAPPED structure that was specified when the overlapped I/O operation was started.
Returns TRUE if the I/O operation has completed, and FALSE otherwise.
Do not call this macro unless the call to GetLastError returns ERROR_IO_PENDING, indicating that the overlapped I/O has started.
To cancel all pending asynchronous I/O operations, use the CancelIo function. The CancelIo function only cancels operations issued by the calling thread for the specified file handle. I/O operations that are canceled complete with the error ERROR_OPERATION_ABORTED.
Minimum supported client
|Windows XP [desktop apps only]|
Minimum supported server
|Windows Server 2003 [desktop apps only]|