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From: eric@snark.uu.net (Eric S. Raymond)
Newsgroups: comp.lang.c
Subject: Re: Structures
Message-ID: <1Vgw5j#17VOVh=eric@snark.uu.net>
Date: 6 Mar 90 15:06:17 GMT
References: <14302@reed.UUCP> <4390@daffy.cs.wisc.edu> <1990Mar5.183244.1013@utzoo.uucp>
Lines: 17

In <1990Mar5.183244.1013@utzoo.uucp> Henry Spencer wrote:
> The main motive for [structure-passing] is when you're essentially
> building your own data types (complex numbers in sci/eng number-crunching,
> two-dimensional coordinates in graphics, etc.) and want to treat them as
> if they were ordinary values.  Passing pointers gets troublesome very
> quickly in such situations.

As usual, Henry is correct. However, speaking as a partisan of ADT design
techniques who likes to build entire program systems as collections of live
data types, I avoid passing structs anyhow. Pointers are significantly faster
to hand around and cheaper to store.

Of course this is not a problem if your type is int size or less. A struct
consisting of two short ints (useful in graphics work, for example) is an
excellent candidate to be passed around by value rather than by address.
-- 
      Eric S. Raymond = eric@snark.uu.net    (mad mastermind of TMN-Netnews)