From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: how to implement a `hook'?
Date:	2 May 2000 14:15:09 GMT
Organization:	Aachen University of Technology (RWTH)
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Jeff Williams <jeffw AT darwin DOT sfbr DOT org> wrote:
> What does it mean to implement a `hook', e.g. to add a `hook' in
> foo.c?  Can someone point me to an instructive example from a
> DJGPP port of a GNU package?

A 'hook' is a general concept, rather than a single method, so without
knowing what you want to hook into, it's impossible to help you in
detail. 

Generally, a 'hook' is usually a sort of 'open end' provided by some
third-party code. If you consider the third-party code base as a big,
impenetrable block of machinery, 'hooks' are a method to add small
bits of extension code to that, which the machinery will recognize and
use, if present. The DJGPP File System Extension (FSEXT) feature is a
collection of such open ends that you can hook your own code into.
-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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