Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!uwvax!tank!mimsy!chris
From: chris@mimsy.UUCP (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Correction, a[33]
Message-ID: <17763@mimsy.UUCP>
Date: 26 May 89 11:21:00 GMT
References: <5819@microsoft.UUCP>
Distribution: usa
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 39

In article <5819@microsoft.UUCP> t-iaind@microsoft.UUCP (Iain Davidson) writes:
>char a[33]
>
>is not an array of 33*sizeof (int)

This much is true (it is size 33*sizeof(char), or 33) ...

>but really 34 slots !!!!!
>
>Remember C is start base 0 not 1.
>
>0..33 = 34 slots of int's.
>
>char a[9]  holds 10 characters !!!!

C is not BASIC.  `char a[9]' holds nine characters, numbered a[0]
through a[8] inclusive.  (Actually, BASICs tend not to be consistent
about allowing a[0].)

And people wonder why microsoft's compilers are buggy :-)

Actually, there is a grain of truth in all this.  Given an array
declaration

	type-name array-name '[' integral-constant-expression ']' ';'

or

	T a[N];

the address &a[N] must be computable.  This sometimes means that
array objects need an extra byte---so that

	int b[K];

actually sets aside K*sizeof(int)+1 bytes, rather than just K*sizeof(int).
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris