Date: Sun, 30 Jan 2000 09:35:14 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: sam <samirw AT connection DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: How Do I catch a "printf interrupt" ?
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On Sat, 29 Jan 2000, sam wrote:

> Are you saying that if parent redirects int 21 to itself and calls another
> program, the startup code will redirect it back to dos?

No, the DJGPP startup code doesn't play any tricks with Int 21h.

For that matter, I don't recommend hooking Int 21h in a DJGPP program
at all.  It's tricky (requires real-mode callbacks, since Int 21h
isn't reflected to protected mode, and real-mode callbacks are
non-reentrant) and dangerous (since paging goes through Int 21h).