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Mail Archives: djgpp/2004/07/17/08:44:54

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Message-ID: <40F92C1B.7090706@012.net.il>
Date: Sat, 17 Jul 2004 15:39:39 +0200
From: alexbodn <alexbodn AT 012 DOT net DOT il>
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To: djgpp AT delorie DOT com
Subject: Re: pointers to structs
References: <1089842517 DOT 34974 AT proxy2 DOT srv DOT ualberta DOT ca>
In-Reply-To: <1089842517.34974@proxy2.srv.ualberta.ca>
Reply-To: djgpp AT delorie DOT com

hi john,

the problem in your program is, that you are trying to initialize the 
struct list pointed at by a random pointer. the pointer list should 
point to a valid structure, obtained through malloc or normal struct 
list variable instantiation.

for example, struct list *plist = malloc(sizeof(struct list)), or 
{struct list list; struct list *plist = &list}

best regards,

alex

φιθεθ John Hanley:

>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?  If I take the 2 assignments out,
>it runs ok.
>
>Any suggestions as to why I can't initialize my head and tail to NULL?
>
>Thanks!
>
>John
>
>
>
>
>  
>

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