Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!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.sys.ibm.pc
Subject: Re: System boot
Message-ID: <25ab3ab5@ralf>
Date: 10 Jan 90 12:37:57 GMT
Sender: ralf@b.gp.cs.cmu.edu
Organization: Carnegie Mellon University School of Computer Science
Lines: 24
In-Reply-To: <9312@leadsv.UUCP>

In article <9312@leadsv.UUCP>, zech@leadsv.UUCP (Bill Zech) wrote:
}INT 19
}        This is a DOS boot ONLY.  The BIOS interrupts are *NOT*
}        reset.  Note that INT 19 is a DOS interrupt, not a BIOS int.

It is *not* a DOS interrupt.  INT 19h is a BIOS interrupt, but points right at
the code with loads and then executes the boot sector.	DOS does not know or
care about INT 19h (except insofar as VDISK.SYS uses a stub INT 19 handler to
locate the data from previous invocations).

}Any TSR or driver which chains onto an interrupt vector must
}intercept int 19, and reload the interrupt vectors with their
}original values, before allowing DOS to handle the int 19.
}Not all TSRs and drivers are friendly enough to do this, and that

Essentially none, in fact.

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"How to Prove It" by Dana Angluin              Disclaimer? I claimed something?
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