NULL pointer dereference in C

Posted by user554125 on Stack Overflow See other posts from Stack Overflow or by user554125
Published on 2010-12-26T04:48:59Z Indexed on 2010/12/26 4:54 UTC
Read the original article Hit count: 202

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c

|

pointers

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null

hey ive got this piece of code. It dereferences a null pointer here. But then there is an and with unsigned int. I really dont understand the whole part. Can someone explain the output.??

struct hi  
{
   long a;  
   int b;  
   long c;  
};  

int main()  
{  
    struct hi ob={3,4,5};  
    struct hi *ptr=&ob;  
    int num= (unsigned int) & (((struct hi *)0)->b);  

   printf("%d",num);  
   printf("%d",*(int *)((char *)ptr + (unsigned int) & (((struct hi *)0)->b)));  
}

The o/p i get is 44 .But how does it work?

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NULL pointer dereference in C - Developer IT

NULL pointer dereference in C

c

pointers

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Related posts about c

Related posts about pointers

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