Message from discussion Expert-Q: (a!=b) != memcmp(&a,&b,sizeof a) ?

From: Alex_K...@scitex.com
Subject: Re: Expert-Q: (a!=b) != memcmp(&a,&b,sizeof a) ?
Date: 1999/06/28
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In article <377738B4.97C7...@hls.via.at>,
  Helmut Leitner <leit...@hls.via.at> wrote:
> Let's assume that a and b have the same basic data type
> (e.g. int, long, float, double ...).
>
> On many platforms it is possible to replace the
> comparisions
>    a==b
>    a!=b
> by
>    memcmp(&a,&b,sizeof(a))==0
>    memcmp(&a,&b,sizeof(a))
>
> What are the conditions that this will not yield the
> desired results?

   I can think of two:
  a) holes in data type representation
  b) +0 and -0 for one's complement platforms


--
        Regards,
                Alex Krol
Disclaimer: I'm not speaking for Scitex Corporation Ltd


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