breck@aimt.UUCP (Robert Breckinridge Beatie) (08/25/87)
I'm trying to take advantage of the wondrous ability to perform i/o operations asynchronously from program execution. I've been able to write the file that I want to write, but have been having trouble with the ioCompletion routine. I haven't been able to find anything that would indicate how the operating system calls the specified routine. Does the toolbox pass any parameters to the completion routine? Does the toolbox make application globals available to the routine? If anyone could point me to a reference, either a pointer into Inside Macintosh or some other source, I'd be very grateful. Also, I've heard a nasty rumour to the effect that the floppy controller takes so much of the cpu's attention that there is absolutely no benefit in doing floppy i/o asynchronously. What little I've been able to get working tends to support this. Does anyone have any hard data on this? Does the scsi controller on Mac+'s suffer from the same problem? (I would call it brain- damage but I'm just getting over a bad sunburn and I don't need the heat) Thanks in advance for any help. -- Breck Beatie uunet!aimt!breck