Accessing structure elements using pointers

Posted by Arun Nadesh on Stack Overflow See other posts from Stack Overflow or by Arun Nadesh
Published on 2011-01-06T08:26:06Z Indexed on 2011/01/06 8:53 UTC
Read the original article Hit count: 362

Filed under:

c

|

pointers

|

structure

Hi Everybody,

Greetings!

I got surprised when the following program did not crash.

typedef struct _x{
int a;
char b;
int c;
}x;
main()
{
x *ptr=0;
char *d=&ptr->b;
}

As per my understanding the -> operator has higher precedence over & operator. So I expected the program to crash at the below statement when we try to dereference the NULL pointer tr.

char *d=&ptr->b;

But the statement &ptr->b evaluates to a valid address. Could somebody please explain where I'm wrong?

Thanks & Regards, Arun

Related posts about pointers

C++ smart pointers: sharing pointers vs. sharing data

as seen on Stack Overflow - Search for 'Stack Overflow'
In this insightful article, one of the Qt programmers tries to explain the different kinds of smart pointers Qt implements. In the beginning, he makes a distinction between sharing data and sharing the pointers themselves: First, let’s get one thing straight: there’s a difference between sharing … >>> More
handling refrence to pointers/double pointers using SWIG [C++ to Java]

as seen on Stack Overflow - Search for 'Stack Overflow'
My code has an interface like class IExample { ~IExample(); //pure virtual methods ...}; a class inheriting the interface like class CExample : public IExample { protected: CExample(); //implementation of pure virtual methods ... }; and a global function to create object of this class - createExample(… >>> More
char pointers & integer pointers (++)

as seen on Stack Overflow - Search for 'Stack Overflow'
i have two pointers, char *str1; int *str2; if i look at the size of both the pointers lets assume str1=4 bytes str2=4 bytes str1++ will increment by 1 byte but if str2++ will increment 4 byte could anybody tell e the concept behind this? >>> More
Smart pointers - cases where they cannot replace raw pointers

as seen on Stack Overflow - Search for 'Stack Overflow'
HI, I have this query about smart pointers. I heard from one of my friends that smart pointers can almost always replace raw pointers. but when i asked him what are the other cases where smart pointers cannot replace the raw pointers,i did not get the answer from him. could anybody please tell… >>> More
C++ Pointers: Number of levels of Indirection

as seen on Programmers - Search for 'Programmers'
In a C++ program that doesn't contain legacy C code, is there a guideline regarding the maximum number of levels of indirection that should be used in the source code? I know that in C (as opposed to C++), some programmers have used pointers to pointers for a multiple dimension array, but for the… >>> More

Developer IT

Accessing structure elements using pointers - Developer IT

Accessing structure elements using pointers

c

pointers

structure

Related posts about c

Related posts about pointers

C++ smart pointers: sharing pointers vs. sharing data

handling refrence to pointers/double pointers using SWIG [C++ to Java]

char pointers & integer pointers (++)

Smart pointers - cases where they cannot replace raw pointers

C++ Pointers: Number of levels of Indirection

Categories cloud