Date: Tue, 4 Nov 1997 13:26:07 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: "Sam." <sam AT greenaum DOT demon DOT co DOT uk>
cc: djgpp AT delorie DOT com
Subject: Re: Taking over the keyboard interrupt
In-Reply-To: <345e4bb9.2352163@news.demon.co.uk>
Message-ID: <Pine.SUN.3.91.971104132528.19533F-100000@is>
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On Mon, 3 Nov 1997, Sam. wrote:

> Is there a tutorial anywhere, explaining step by step what to do, in
> fairly plain C? It doesn't have to be efficient or useful, just a
> minimum to illustrate the point of how to install and deinstall an
> interrupt and how to lock the right memory.

If you write hardware interrupts in C, you will need to lock all of
the memory (with a crt0 flag, see the FAQ).  Otherwise, you will risk
crashing, or will need to use tricks which are not guaranteed to work
with all compiler versions.

The DJGPP FAQ list has a step-by-step explanation in section 18.9,
which should get you off the ground.  If you have questions about some
of the details, I suggest posting specific questions about specific
issues.