Date: Tue, 12 Jun 2001 11:10:14 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Pierre Muller <muller AT cerbere DOT u-strasbg DOT fr>
cc: djgpp-workers AT delorie DOT com, Charles Sandmann <sandmann AT clio DOT rice DOT edu>
Subject: Re: Interrupt 0x24 problem ?
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On Mon, 11 Jun 2001, Pierre Muller wrote:

> Interrupt 0x24 (and possibly 0x23)
> are not disabled when exiting from a DJGPP
> program.

Correct.

>    But the exit code disables the 32 code selector
> that is used for this interrupt, which means that this interrupt
> will point to an invalid location
> until the OS restores the previous values...
> 
>    Isn't this a potential source of crashes ?

Where do you see the selector of __djgpp_i24 being invalidated in the
exit code?  AFAIK, that selector is CS, and it is valid until the
program exits, at which time it is released by the DPMI host.  The
DPMI host handles Int 24h (and 23h) specially, so it should clean them
up before releasing the selector.

In any case, the DPMI host normally automatically fails any Int 24h
calls, without letting them get to the client.  The only exception I
know of is QDPMI.