Go4Expert - Pointer confusion! URGENT!!

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Pointer confusion! URGENT!!

Hi I have got stuck bcos of this unexpected result .. Can someone Aid???

Program:

Code:

#include <stdio.h>



typedef struct tStruct

{

    int a;

    int b;

    int c;

}tStruct;



tStruct *temp1;



void func1(tStruct *node)

{



    temp1 = (tStruct*)malloc(sizeof(tStruct));

    printf("\n Address of the node : %u",temp1);



    node = temp1; // I doubt this part.

    node->a = 1;

    node->b = 2;

    node->c = 3;

    printf("\n Value of a : %u",temp1->a);

    printf("\n Value of b : %u",temp1->b);

    printf("\n Value of c : %u",temp1->c);

}



main()

{

    tStruct *temp=0;

    func1(temp);

    printf("\n Address of the node : %u",temp);

    printf("\n Value of a : %u",temp->a);

    printf("\n Value of b : %u",temp->b);

    printf("\n Value of c : %u",temp->c);

}

Result:

Address of the node : 2500
Value of a : 1
Value of b : 2
Value of c : 3
Address of the node : 0
Value of a : 0
Value of b : 0
Value of c : 30036

I need to view the values of the the node in the main() function. But am unsuccessful.

Thanks in Advance.

Cheers,
Kart.

Re: Pointer confusion! URGENT!!

Hi,
From main you are passing temp by value, to achieve desired result you should pass temp by address.
Like

Code:

#include <stdio.h>



typedef struct tStruct

{

    int a;

    int b;

    int c;

}tStruct;



tStruct *temp1;

void func1(tStruct **node)

{



    temp1 = (tStruct*)malloc(sizeof(tStruct));

    printf("\n Address of the node : %u",temp1);



    *node = temp1; // I doubt this part.

    (*node)->a = 1;

    (*node)->b = 2;

    (*node)->c = 3;

    printf("\n Value of a : %u",temp1->a);

    printf("\n Value of b : %u",temp1->b);

    printf("\n Value of c : %u",temp1->c);

}





main()

{

    tStruct *temp=0;

    func1(&temp);

    printf("\n Address of the node : %u",temp);

    printf("\n Value of a : %u",temp->a);

    printf("\n Value of b : %u",temp->b);

    printf("\n Value of c : %u",temp->c);

}

Re: Pointer confusion! URGENT!!

thanks Dinesh.. it indeed solved the problem!!