Structure Pointer in C

In C programming, a structure pointer is a pointer that points to a structure variable. Using structure pointers makes it easier to access and manipulate the members of a structure, especially when passing structures to functions.

Structure Pointer in C

Declaration of Structure Pointer

struct struct_name {

    data_type member1;

    data_type member2;

    …

};

struct struct_name *ptr;

• struct_name – Name of the structure.
• ptr – Pointer variable to store the address of the structure.

Accessing Structure Members via Pointer

To access structure members using a pointer, we use the arrow operator -> instead of the dot operator ..

ptr->member_name

This is equivalent to:

(*ptr).member_name

Example: Using Structure Pointer

#include <stdio.h>

#include <string.h>

struct Student {

    int roll_no;

    char name[50];

    float marks;

};

int main() {

    struct Student s1;

    struct Student *ptr;

    // Assigning values

    ptr = &s1;  // Pointer points to structure s1

    ptr->roll_no = 101;

    strcpy(ptr->name, “Rahul”);

    ptr->marks = 95.5;

    // Accessing structure members

    printf(“Roll No: %d\n”, ptr->roll_no);

    printf(“Name: %s\n”, ptr->name);

    printf(“Marks: %.2f\n”, ptr->marks);

    return 0;

}

Output:

Roll No: 101

Name: Rahul

Marks: 95.50

Passing Structure Pointer to Functions

Passing a structure pointer to a function saves memory and allows the function to modify the original structure.

#include <stdio.h>

#include <string.h>

struct Student {

    int roll_no;

    char name[50];

    float marks;

};

void display(struct Student *s) {

    printf(“Roll No: %d\n”, s->roll_no);

    printf(“Name: %s\n”, s->name);

    printf(“Marks: %.2f\n”, s->marks);

}

int main() {

    struct Student s1 = {101, “Rahul”, 95.5};

    display(&s1);  // Pass structure pointer

    return 0;

}

Output:

Roll No: 101

Name: Rahul

Marks: 95.50

Advantages of Structure Pointers

1. Efficient memory usage – avoids copying the whole structure when passing to functions.
2. Easy access to structure members dynamically.
3. Allows modification of original structure values within functions.
4. Useful when working with arrays of structures and dynamic memory allocation.

Summary

• Structure pointer points to the memory location of a structure variable.
• Access structure members using -> or (*ptr). syntax.
• Passing structure pointers to functions is memory efficient.

POP- Introduction to Programming Using ‘C’

DS – Data structure Using C

OOP – Object Oriented Programming 

Java Programming

DBMS – Database Management System

RDBMS – Relational Database Management System