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From: kocks@jessica.stanford.edu (Peter Kocks)
Newsgroups: comp.sys.mac.programmer
Subject: Re: NULL pointer problem in THINK_C? Solution...
Keywords: THINK_C,bug
Message-ID: <1990Aug16.171844.17125@portia.Stanford.EDU>
Date: 16 Aug 90 17:18:44 GMT
References: <1990Aug14.164700.146@portia.Stanford.EDU>
Sender: news@portia.Stanford.EDU (USENET News System)
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Thanks to all those who replied...

This was an interesting bug (for me anyway).
I was using a linked list with nodes of the following form:

	char string[100];
        node_ptr  next;

I accidently changed the 101 element of string in the program.  This
changed next a little bit, but not enough to show up in the debugger
(that is, the debugger showed next == NULL).  So, when I transversed
the list, I went right off the end.  

Thanks again for help.

-- Peter Kocks
   kocks@jessica.stanford.edu