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From: xwang@gmuvax2.gmu.edu (Xiang-Min Wang)
Newsgroups: comp.lang.c
Subject: Re: Array question
Message-ID: <3675@gmuvax2.gmu.edu>
Date: 2 Mar 91 04:49:51 GMT
References: <EbhAAgG00WBNM2PIt_@andrew.cmu.edu> <9304@hub.ucsb.edu>
Reply-To: xwang@gmuvax2.UUCP (Xiang-Min Wang)
Organization: George Mason Univ. Fairfax, Va.
Lines: 26
email: xwang@gmuvax2.gmu.edu

In article <9304@hub.ucsb.edu> tomkwong@banana.UUCP (Thomas K. Kwong) writes:
>In article <EbhAAgG00WBNM2PIt_@andrew.cmu.edu> rg2c+@andrew.cmu.edu (Robert Nelson Gasch) writes:
>>
>>    int *this_ptr;
>>    this_ptr [0] = 1;
>>    this_ptr [1] = 2;
>>    . . . 
>>    this_ptr [9] = 10;
>>
>>This works fine, but I really don't know why?? It seems you're using
>>memory to store an array which was never really allocated. 

Please notice that althouhg the pointer 'this_ptr', after declared, is 
not initialized by YOU (I am not sure the C compiler will initialize 
it to zero or not), it bears some value (as an address) ANYWAY. 
Therefore, you can do the "normal" things to it like the assignment:

	this_ptr[i] = i (or *(this_ptr+i) = i )

Simply speaking, your program is SYNTACTICALLY correct, but FUNCTIONALLY
wrong.

xwang

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