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From:	Martin Ambuhl <mambuhl AT earthlink DOT net>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: pointers to structs
Date:	Wed, 14 Jul 2004 19:07:15 -0400
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John Hanley wrote:

> I am creating a linked list.  I have 2 structs:
> 
> struct data_record
> {
>     struct data_record * next;
> };
> 
> struct data_list
> {
>     struct data_record * head;
>     struct data_record * tail;
> };
> 
> int main()
> {
>     struct data_list * list;
> 
>     list->head = NULL;
>     list->tail = NULL;
> }
> 
> When I compile then run this, I get:  "Exiting due to Signal SIGSEGV.  Page
> Fault at ..."
> 
> Can I not assign NULL to these pointers? 

There are no pointers, except for 'list', which points nowhere.  'list' 
needs to have storage allocated for it to point to before there are any 
list->head or list->tail to use.

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