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From: gvrod@CCVAX.IASTATE.EDU (R Eldridge, VAX Systems)
Newsgroups: comp.sys.apple2
Subject: Re: Identify a ProDOS disk?
Message-ID: <0094360D.2E76F600@VAXF.IASTATE.EDU>
Date: 28 Jan 91 14:44:39 GMT
References: <25235@fs1.NISC.SRI.COM>,<48546@apple.Apple.COM>
Sender: news@news.iastate.edu (USENET News System)
Reply-To: gvrod@CCVAX.IASTATE.EDU (R Eldridge, VAX Systems)
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Organization: Iowa State University, Ames, IA.
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In article <25235@fs1.NISC.SRI.COM> cwilson@NISC.SRI.COM (Chan Wilson [Animal]) writes:
>How is it possible to identify a ProDOS disk?  I'm looking for a magic
>number of some sorts, someplace, anywhere. 
>
>Ideally, it'd be a magic number someplace near the front.  I'm into dealing
>with disks as data streams at the moment...
>
>Hep Me!
>
>--Chan
>
>Chan Wilson                                  Chief Hard-Question Answer Person
SRI Intl. Network Information Systems Center
>333 Ravenswood Ave., EJ287			Internet: cwilson@nisc.sri.com
>Menlo Park, CA., 94025				Phone: (415)859-4492
>    "If I want to be a surfer this month, I bloody well will be."

how about just calling the ON_LINE function for the device. according to
the prodos-8 technical reference manual, ON_LINE can return error number
$52 (not a prodos disk)
============ 
rod eldridge                     gvrod@isuvax.bitnet
vax systems                      gvrod@isuvax.iastate.edu
iowa state university
bus: (515) 294-7498              postmaster@isuvax.bitnet
fax: (515) 294-1717              postmaster@isuvax.iastate.edu