Path: utzoo!utgpu!attcan!uunet!mcvax!hp4nl!botter!star.cs.vu.nl!maart
From: maart@cs.vu.nl (Maarten Litmaath)
Newsgroups: comp.lang.c
Subject: Re: Unions
Keywords: What can they be used for?
Message-ID: <1559@solo8.cs.vu.nl>
Date: 21 Oct 88 16:32:19 GMT
References: <322@hrc.UUCP> <1532@valhalla.ee.rochester.edu>
Reply-To: maart@cs.vu.nl (Maarten Litmaath)
Organization: VU Informatica, Amsterdam
Lines: 17

\In article <322@hrc.UUCP>, dan@hrc.UUCP (Dan Troxel VP) writes:
\
\ Except for the memory savings, what are Unions suited for?

Beside reasons mentioned so-far, there's alignment:

	union	_u {
			int	i;
			char	buf[17];
		} u;

This construct will let you safely read an integer starting at &u.buf[0],
i.e. no bus error will occur.
K&R: a union can be thought of as a struct, all whose fields begin at offset 0.
-- 
Hippic sport:                         |Maarten Litmaath @ Free U Amsterdam:
             a contradiction in terms.|maart@cs.vu.nl, mcvax!botter!maart