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From: mandel@vax.anes.tulane.edu (Jeff E Mandel MD MS)
Newsgroups: comp.sys.mac.programmer
Subject: Re: trapping for floppy disk
Message-ID: <6761@rex.cs.tulane.edu>
Date: 25 Mar 91 01:48:35 GMT
References: <1991Mar19.164204.8847@hubcap.clemson.edu>
Sender: news@rex.cs.tulane.edu
Reply-To: mandel@vax.anes.tulane.edu
Organization: Tulane University School of Medicine
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In article <1991Mar19.164204.8847@hubcap.clemson.edu>, mcmac@hubcap.clemson.edu (Scott McAlister) writes:
>I am working on an init that traps on MountVol.  What I want to do
>is to distinguish between floppies and hard disks.  Can anybody help 
>me out?  Sample code would be appreciated.  Thanks in advance.
>
I had to figure this out once, and I seem to recall deciphering it from the
Volume Control Block's vcbDrvNum field. I believe (but it may ONLY be a belief)
that this was always 1 or 2 for floppies. In any event, if you have to be
absolutely safe, you can walk the Drive Queue and check the flag bytes of the
Drive Queue Element for that drive number; byte 1 will tell you if the volume
is ejectable. See Inside Mac Vol IV pp 176-182 for confusion in greater depth.


Jeff E Mandel MD MS
Asst. Professor of Anesthesiology
Tulane University School of Medicine
New Orleans, LA
mandel@vax.anes.tulane.edu