Path: utzoo!mnetor!uunet!husc6!bbn!rochester!cornell!batcomputer!itsgw!imagine!pawl23.pawl.rpi.edu!jesup
From: jesup@pawl23.pawl.rpi.edu (Randell E. Jesup)
Newsgroups: comp.sys.amiga
Subject: Re: one last word on my simple device problem
Message-ID: <181@imagine.PAWL.RPI.EDU>
Date: 24 Dec 87 08:35:41 GMT
References: <897@louie.udel.EDU>
Sender: news@imagine.PAWL.RPI.EDU
Reply-To: beowulf!lunge!jesup@steinmetz.UUCP
Distribution: na
Organization: RPI Public Access Workstation Lab - Troy, NY
Lines: 32

In article <897@louie.udel.EDU> rminnich@udel.EDU (Ron Minnich) writes:
>  Problem is that, for example, if i do a DoIO, internet.device
>eventually responds, when it is all done, with a ReplyMsg. Then
>the DoIO returns. All subsequent DoIOs return immediately, i.e.
>long before the ReplyMsg in the device. So, somehow a bit of state
>(pun intended- though it may be more than one bit) gets set and 
>is not getting properly cleared somewhere else. The DoIOs always
>return 0, so it is not as though there is an error occuring. Also, 
>internet.device registers the incoming io requests. But, the telnet 
>program performing the DoIO does not block until the ReplyMsg- DoIO
>returns immediately (i.e. incorrectly) on the second and succeeding 
>operations.

	Aha!  I'll assume you are just using DoIO, no WaitIO's (as in
the previous message - I'd assumed you were using SendIO or BeginIO).
Note that DoIO always tries Quick IO first, then normal IO if it fails.
SendIO never uses QUICK, and BeginIO allows you to play.  See the discussion
Quick io in the RKM under IO.  The device has certain responsibilites when
it comes to clearing/whatever the quick bit, depending on how it is
processed (quick or not).  Note many devices support quick for only a few
commands, the rest have to wait for completion.
	( 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.
	)

     //	Randell Jesup			Lunge Software Development
    //	Dedicated Amiga Programmer	13 Frear Ave, Troy, NY 12180
 \\//	lunge!jesup@beowulf.UUCP	(518) 272-2942
  \/    (uunet!steinmetz!beowulf!lunge!jesup)