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From: drw@cullvax.UUCP (Dale Worley)
Newsgroups: comp.lang.c
Subject: How big is a (??? *)
Message-ID: <1217@cullvax.UUCP>
Date: Wed, 27-May-87 10:40:09 EDT
Article-I.D.: cullvax.1217
Posted: Wed May 27 10:40:09 1987
Date-Received: Fri, 29-May-87 06:11:25 EDT
Organization: Cullinet Software, Westwood, MA, USA
Lines: 24

doug@edge.UUCP (Doug Pardee) writes:
> I want to do what is sometimes called "object-oriented" programming.
> Each source module consists of a bunch of routines which operate on a
> particular kind of object.  Each instance of an object is described in
> detail by a struct which is malloc'ed by the object's "create" routine.
> [...]
> Unfortunately, as we've seen, that means that the outside world doesn't
> even know how big the pointer is.  So, it seems that I can't use the
> straightforward approach of having the handle be the pointer to the
> structure.

My taste is that the cleanest method is to say:

typedef char *handle;

Now, cast everything to and from 'handle' -- by ANSI C, casting a
pointer to char * and back is guaranteed to not screw up.

Dale
-- 
Dale Worley		Cullinet Software
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