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Date: Tue, 5 Mar 2002 12:28:49 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: IeperNaum <zandro_arceo AT support DOT trendmicro DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: Hooking INT 2F
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On 5 Mar 2002, IeperNaum wrote:

> i tried to build the sample tsr, and it worked. then i changed the
> interrupt from int 8 to 2f, modified the int2f handler to make the
> program beep.
> 
> but it did not work.

Int 2Fh is a software interrupt, not a hardware interrupt.  Software 
interrupts are not reflected to protected-mode handlers (says the DPMI 
spec), so you need either to hook them in real mode or to use real-mode 
callbacks, as explained in section 18.9 of the DJGPP FAQ list.