Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!boulder!tramp!savage
From: savage@tramp.Colorado.EDU (SAVAGE CHARLES L)
Newsgroups: comp.lang.c
Subject: Re: pointer & struct
Message-ID: <6427@boulder.Colorado.EDU>
Date: 7 Feb 89 02:05:36 GMT
References: <7208@pyr.gatech.EDU>
Sender: news@boulder.Colorado.EDU
Reply-To: savage@tramp.Colorado.EDU (SAVAGE CHARLES L)
Distribution: usa
Organization: University of Colorado, Boulder
Lines: 37

In article <7208@pyr.gatech.EDU> dvu@pyr.gatech.EDU (Dinh Vu) writes:
>The small program below compiled fine, but
>it gave core dump when I run it.  Would someone give me 
>some light on this matter.
>
>	 #include <stdio.h>
>	
>	struct abc {
>		int x;
>		int y;
>	};
>
>	main()
>	{
>		struct abc *var;
--------------->var = (abc *) malloc ((unsigned) sizeof(struct abc));
>		var->x = 5;
>		var->y = 10;
>	}
>
Sombody has probably already fixed this error, but you must alocate
memory for the pointer to point too.  If not, all the pointer has is a 
random address, and when you assign a value to the pointer it overwrites
some memory in storage that may be used by your source code or may not be
yours at all.

Savage.





	
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