Date:	Tue, 15 Feb 2000 09:52:06 +0200 (IST)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender:	eliz AT is
To:	arcadepreserv AT hotmail DOT com
cc:	djgpp AT delorie DOT com
Subject:	Re: How Do I start another DOS program from DJGPP ?
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On Mon, 14 Feb 2000 arcadepreserv AT hotmail DOT com wrote:

> Does this mean that this approach is possible ? If set up with a proper
> timer interrupt ?

What approach?  I thought I just explained that neither of the two
approaches discussed here will work.  Reading a file from a hardware
interrupt handler is a no-no because DOS is non-reentrant, while doing
so with a signal handler will not work because all signals are
deferred until the child program exits.

> Can I in DOS compiled by DJGPP have a file open fron the child
> program, and read the same file from the interrupt handler ?

The only practical way is to hook Int 21h, monitor file I/O functions,
and steal the text written by the child when you see it.

However, hooking Int 21h from a DJGPP program is a mess: you need to
use the real-mode callback facility, which is non-reentrant in its
current implementation, and there are complications because virtual
memory also uses DOS calls.

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