Path: utzoo!mnetor!uunet!husc6!rutgers!sdcsvax!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga
Subject: Re: one last word on my simple device problem
Message-ID: <8712241144.AA26621@cory.Berkeley.EDU>
Date: 24 Dec 87 11:44:46 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 23

>	 Essentially, this is what DoIO does: 
>		Set IOF_QUICK bit. 
>		Do a BeginIO 
>		check to see if quick bit still set, if so, return.
>		else do a SendIO, then a WaitIO, then return.

	'Essentially' is right!  But you left out one important fact:

	DoIO() not only sets the IOF_QUICK bit, but clears all the other
	bits in the Flags field!

	Realizing that you are putting it into terms anybody can understand,
	but still a stickler for accuracy (even if my spelling is a bit odd
	this early in the morning), DoIO() doesn't actually start up a
	SendIO()... the Begin() did that when the device driver found it
	could not do the request syncronously.  The reply port is actually
	supplied by the device driver (I think.. at least it is NOT supplied
	by the DoIO() function, and NOT by the user, so that leaves the 
	device driver!)

				-MaWTT  er, -Matt