Coridon Henshaw wrote in a message to Peter Fitzsimmons:

 PF> Yes -- particularly if the drives are on separate disk
 PF> controllers; OS/2 can get all the non-pio ones busy at the same time.

 CH> Would there be any advantage in a mixed PIO IDE and
 CH> DMA/busmaster SCSI system? 

In my opinion, there is never an advantage to having a PIO IDE device.

 PF> or let the user tell you some how (this might be desirable, since a
 PF> remote drive can't be inspected with an ioctl).

 CH> As I recall, the category 9 IOCTLs require that the drive be
 CH> locked, which is something I can't do because the program
 CH> will be running from the same drive that it is checking.  It
 CH> will also need to check the boot drive. 

You need to have the lock asserted in order to do certain things, and the
official recommendation is that you assert a lock for any IOCtl.  However,
if you can risk the small possibility of inconsistent results and are only
reading information, then you can get away without asserting a lock.

 CH> Not to mention that I've already lost a bunch of data and
 CH> one hard drive this week, so I don't think I'll mess around
 CH> with the category 9 IOCTLs just yet. :-) 

If you are playing with this sort of thing, you need a disposable machine.

 CH> I'll guess take the easy way out and just ask the user which
 CH> logical drives can be scanned at the same time.

I really don't think it is worth the effort to worry about it at all.
 
-- Mike


---