bug in DOS 2.00 -- divide by zero causes crash

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1 total messages Started by bet Sat, 18 Feb 1984 00:45

Author: bet
Date: Sat, 18 Feb 1984 00:45

19 lines
1153 bytes

I seem to have discovered a bug in DOS 2.00. Zero-divide interrupts aren't
correctly trapped, so dividing by zero causes a crash. DOS 1.00 and 1.10
caught the interrupt, reported "Divide Overflow", and returned to DOS.
Make the following a .com file: (it's easy with the 2.00 debugger)

	xor	dx,dx
	mov	ax,10
	xor	cx,cx
	div	cx
	int	20

Now run it under DOS 1.00 or 1.10. Divide Overflow. DOS 2.00: space shot.
If anyone has an interrupt handler written (preferably as an end-and-remain-
resident .com file) please let me know. I am trying to write one, but keep
getting "memory allocation error, cannot load COMMAND.COM. System halted".
when I try it out with the above test file.
					{decvax,akgua}!mcnc!ecsvax!bet
					Bennett Todd

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