Date: Mon, 20 Dec 93 13:46:58 EST
From: peprbv AT cfa0 DOT harvard DOT edu (Bob Babcock)
To: jakobs AT ldv01 DOT Uni-Trier DOT DE
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Testing for a disk in Drive A: / B:

> I need a routine to check for the existence of a readable floppy
> in either drive A: or B:, without getting the DOS message "Abort/Fail/Retry"

I just got something like this working a few days ago.  What I did was to
install a real-mode critical error handler which tells DOS to fail the disk
operation and sets a flag which I can test from protected mode.  Or,
rri!potter AT vtserf DOT cc DOT vt DOT edu (Mark Allen Potter) sent me some sample code which
works by a real mode callback.  I can send you a copy of my code tonight or
post it if it is of general interest.