Path: utzoo!attcan!uunet!decwrl!sdd.hp.com!ucsd!tut.cis.ohio-state.edu!pt.cs.cmu.edu!b.gp.cs.cmu.edu!Ralf.Brown@B.GP.CS.CMU.EDU
From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.os.msdos.programmer
Subject: Re: Boot sector parameter table tricks
Message-ID: <26ada268@ralf>
Date: 25 Jul 90 13:45:12 GMT
Sender: ralf@b.gp.cs.cmu.edu
Organization: Carnegie Mellon University School of Computer Science
Lines: 13
In-Reply-To: <1990Jul25.103239.8778@canterbury.ac.nz>

}P.S. Does anyone know what the "NON-IBM" bit actually does in the attributes of
}a block device? Does anything use it?

If clear, DOS passes the driver a pointer to the first sector of the FAT
for the "Build BPB" call.  If set, it passes a pointer to a scratch
buffer with which the driver may do anything it pleases.  The upshot is
that drivers without the "NON-IBM" bit can not support multiple media
whose first FATs start at different locations on the disk.
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