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From: xwang@gmuvax2.gmu.edu (Xiang-Min Wang)
Newsgroups: comp.lang.c
Subject: Re: Global and Extern Pointers, Arrays
Message-ID: <1991May30.210730.18222@gmuvax2.gmu.edu>
Date: 30 May 91 21:07:30 GMT
References: <AJ3U.91May22202642@agate.cs.virginia.edu>
Distribution: comp
Organization: George Mason University, Fairfax, Va.
Lines: 31

In article <AJ3U.91May22202642@agate.cs.virginia.edu> aj3u@agate.cs.virginia.edu (Asim Jalis) writes:
>I just figured out the following bug in my program.  I had a global
>array, with some initialized value that I was also declared an extern
>pointer in the other files that accessing it.  This turns out to be a
>no-no.  The bug went away when I changed the extern definition to an
>array also.  
>
>Here is the code:
>
>file.1
>	struct x px[1] = { ... };
>
>file.2
>	extern *px	/* boinks */
>	extern px[]	/* works */
>
>Any ideas as to why this is?
>
>Asim Jalis.

Hi, Asim. in your file 'file.2', you should declare px as  

         extern struct x px[1]

telling the compiter that px[1] is of type 'struct x' but do not need bother
allocating memory for it. 

as to why your second solution works, well, there are a lot of luck out there
in c programming. so good luck.

xwang