Re: Asynchronous (overlapping) file access

So there should be a difference, when timer_2 is stopping immediately after
the call to WriteFile, and timer_1 is stopping after the while loop with
HasOverlappedIoCompleted? Am I right? But the difference I measure is only 2
ms... So I thought I might still be using synchronous file access...

I tried 2 WriteFile calls back-to-back:
------------8<-------------------------------------8<-----------
    result = WriteFile( h_file[0], buffer_address[0],
(DWORD)bytes_to_write_aligned, &bytes_written[0], &overlapped[0] );
    result = WriteFile( h_file[1], buffer_address[1],
(DWORD)bytes_to_write_aligned, &bytes_written[1], &overlapped[1] );

    timer_2.Exit();

    // Wait till write is completed.
    while (!HasOverlappedIoCompleted( &overlapped[0] ));
    while (!HasOverlappedIoCompleted( &overlapped[1] ));

    result = CloseHandle( h_file[0] );
    result = CloseHandle( h_file[1] );

    timer_1.Exit();

------------8<-------------------------------------8<-----------

timer_2 takes the time immediately after the WriteFile calls, and timer_1
takes the time after waiting for the file access to be finished. Here they
are also only 2 ms (or even less) apart.

As you said, I hoped to use asynch. IO, so that I could do other things
while the disk is busy, but somehow I can't get it to work...

Regards,
Claus