Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!apple!REEKES@applelink.apple.com
From: REEKES@applelink.apple.com (Jim Reekes)
Newsgroups: comp.sys.mac.programmer
Subject: Re: read,ASYNC
Message-ID: <13826@goofy.Apple.COM>
Date: 2 Jun 91 01:08:43 GMT
References: <178@iitinc.UUCP>
Sender: usenet@Apple.COM
Organization: Apple Computer, Inc.
Lines: 20

In article <178@iitinc.UUCP>, hedley@iitinc (Hedley Rainnie) writes:
> 
> Hello. A coworker and I are trying read,ASYNC and find that it behaves
> like regular read. How we determine that is by reading a large block
> from a file and the call doesn't return until a lot of disk activity 
> completes. I can understand that on a cheap mac maybe the two could be
> the same but this in on a IIfx. I havn't found a reasonable def'n of
> what read,ASYNC will do for me, I had hoped to get a non-blocking file
> read. Has anyone found a way to get a non-blocking file read? 

HFS is asychronous, but the SCSI Manager is not.  So reading from a SCSI
disk will always be done synchronously.  Floppies and servers do read/write
asychronously.

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Jim Reekes, E.O.             |     Macintosh Toolbox Engineering
                             |          Sound Manger Expert
Apple Computer, Inc.         | "All opinions expressed are mine, and do
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