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From: roemer@cs.vu.nl (Roemer Lievaart)
Newsgroups: comp.lang.c
Subject: Re: Addition of pointers
Message-ID: <2459@solo12.cs.vu.nl>
Date: 8 May 89 17:03:29 GMT
References: <2765@buengc.BU.EDU> <563@lzaz.ATT.COM> <4093@ficc.uu.net> <2299@mit-caf.MIT.EDU>
Organization: V.U. Informatica, Amsterdam, the Netherlands
Lines: 20

vlcek@mit-caf.MIT.EDU (Jim Vlcek) writes:

>In article <4093@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>>In article <563@lzaz.ATT.COM>, hutch@lzaz.ATT.COM (R.HUTCHISON) writes:
>>> 	midpoint_pointer = (start_pointer + end_pointer) / 2;
>>
>>You're right. It's a valid operation.

It is not. It is a wrong way to write:
	midpoint_pointer = start_pointer + (end_pointer - start_pointer) / 2;

>In what sense?  It's invalid C, that's for sure.

It's invalid anyway: addition of pointers is in general nonsense.
It may make sense to take the average of two pointers, but not by defining
it in ways of two senseless operations (on pointers): addition and division.
____________________________________________________________________________
Roemer B. Lievaart | "Wa:a:na:a: das Soogo! Schnell!" "GRONF!" "Ich krich die
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