deep confuse with pointer

Hi,

I am deeply confuse with pointer after so many reading

Pointer is variable that hold memory location of variable. variable may be a different type like int, char, float..

I am confused with pointer to structure.

Code:

---

#include<stdio.h>

struct structure_name
{
    int i;
    char c;
    float f;
    struct structure_name * n;
}


int main ()
{
    struct structure_name * structure_variable = NULL;
   
    structure_variable = malloc (sizeof(structure_variable));

    structure_variable->i;
    structure_variable->c;
    structure_variable->f;


    return 0;   
}

---

Does pointer store the memory location of structure or location of structure member?

structure_variable->i; Pointer hold the memory location of structure member i variable i is integer variable

Quote:

---

Originally Posted by Parth12

Does pointer store the memory location of structure or location of structure member?

---

It stores the address of the structure object.

This address is the same in value as one of the members of the struct object (i.e., the first) because the struct object consists of these members, but it is different in type.

Quote:

---

Originally Posted by laserlight

It stores the address of the structure object.

---

Code:

---

#include<stdio.h>
#include<stdlib.h>
 
struct structure_name
{
    int i;
    char c;
    float f;
    struct structure_name * n;
};
 
 
int main ()
{
    struct structure_name * structure_variable = NULL;
   
    structure_variable = malloc (sizeof(structure_variable));
 
    structure_variable->i;
    structure_variable->c;
    structure_variable->f;
   
    printf("pointer of structure : %p \n", structure_variable);
   
    printf("memory location of first object of structure : %p \n", &(structure_variable->i ));
   
    printf("memory location of second object of structure : %p \n", &(structure_variable->c ));
     
      printf("memory location of third object of structure : %p \n", &(structure_variable->f ));
 
 
    return 0;   
}

---

pointer of structure : 007113A8
memory location of first object of structure : 007113A8
memory location of second object of structure : 007113AC
memory location of third object of structure : 007113B0

something better then previous

Code:

---

#include<stdio.h>
#include<stdlib.h>
 
struct structure_name
{
    int i;
    char c;
    float f;
    struct structure_name * n;
};
 
 
int main ()
{
    struct structure_name * structure_variable = NULL;
   
    structure_variable = malloc (sizeof(structure_variable));
 
    structure_variable->i = 100;
    structure_variable->c = 'x';
    structure_variable->f = 23.30;
   
    printf("pointer of structure : %p \n", structure_variable);
   
    printf("memory location of first object of structure : %p \n", &(structure_variable->i ));
   
    printf("memory location of second object of structure : %p \n", &(structure_variable->c ));
     
    printf("memory location of third object of structure : %p \n", &(structure_variable->f ));
 
   
    printf("pointer point to the loaction  %p of first object of structure where  i is : %d \n", &(structure_variable->i ), (structure_variable->i ));
   
    printf("pointer point to the loaction  %p of second object of structure where  c  is : %c \n", &(structure_variable->c ), (structure_variable->c ));
   
    printf("pointer point to the loaction  %p of third object of structure where  f is : %f \n", &(structure_variable->f ), (structure_variable->f ));
     
    return 0;   
}

---

pointer of structure : 00B413A8


memory location of first object of structure : 00B413A8

memory location of second object of structure : 00B413AC

memory location of third object of structure : 00B413B0

pointer point to the loaction 00B413A8 of first object of structure where i is : 100

pointer point to the loaction 00B413AC of second object of structure where c is : x

pointer point to the loaction 00B413B0 of third object of structure where f is : 23.299999

By the way, this line:

Code:

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structure_variable = malloc (sizeof(structure_variable));

---

should be:

Code:

---

structure_variable = malloc (sizeof(*structure_variable));

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because you want to allocate enough memory to hold an object that structure_variable points to (a struct structure_name), not just enough memory to hold a pointer to a struct structure_name.