• Skip to main content
  • Skip to primary sidebar
  • Skip to secondary sidebar
  • Skip to footer

Computer Notes

Library
    • Computer Fundamental
    • Computer Memory
    • DBMS Tutorial
    • Operating System
    • Computer Networking
    • C Programming
    • C++ Programming
    • Java Programming
    • C# Programming
    • SQL Tutorial
    • Management Tutorial
    • Computer Graphics
    • Compiler Design
    • Style Sheet
    • JavaScript Tutorial
    • Html Tutorial
    • Wordpress Tutorial
    • Python Tutorial
    • PHP Tutorial
    • JSP Tutorial
    • AngularJS Tutorial
    • Data Structures
    • E Commerce Tutorial
    • Visual Basic
    • Structs2 Tutorial
    • Digital Electronics
    • Internet Terms
    • Servlet Tutorial
    • Software Engineering
    • Interviews Questions
    • Basic Terms
    • Troubleshooting
Menu

Header Right

Home » C » Pointer » Type Casting Of Pointers in C
Next →
← Prev

Type Casting Of Pointers in C

By Dinesh Thakur

We saw that pointer values may be assigned to pointers of same type. However, pointers may be type cast from one type to another type. In the following code lines, A is an int type variable, D is variable of type double, and ch is a variable of type char. Pa is declared as a pointer to int variables, Pd is declared as a pointer to double type variables, and Pc is declared as pointer to character type variables. Pa is assigned the value &A.

int A= 150, *Pa;
Pa = &A;
double D, *Pd;
char ch, *Pc,

The code Pd = Pa is illegal; however, we may type cast Pd to type int by the following code:

Pd = (int*)Pd;

After type casting, the following assignment becomes legal:

Pd = Pa;

Similarly, Pc may be type cast to type int and assigned the value Pa.

(int*)Pc = pa;

After the execution of the above code all the three pointers, i.e., Pa, Pd, and Pc, point to the value 150.

       

Note the difference between the type casting of a variable and type casting of a pointer. Taking the above declarations of A, D, ch of the type int, double, and char, respectively. For type casting of D into type int, the code is

D = (int)D;

While for type casting a double pointer Pd into pointer for int the code is as below.

Pd = (int*)pd;

Illustrates assigning of pointers and addresses

#include<stdio.h> 
void main ()  { 
 int n = 10, m= 20, * pn, * pm; 
 char ch = 'H' , *pch; 
 double x = 3.650 ; 
 float y=5.5, *py = &y; 
 double * px = &x; 
 clrscr(); 
 pn = &n; //pointer pn is assigned value &n. 
 pm = &m; //Pointer is assigned value &m 
 pch = &ch; // pointer pch is assigned value &ch. 
 printf("n = %d\t x = %.31f\t ch = %c\n", n, x, ch); 
 printf("*pn= %d,\t*pm = %d,\t *pch = %c\n",*pn, *pm,*pch); 
 printf("*px = %.3lf\n", *px); 
 pm= pn ; // pm is assigned the value of pn. Both of same type. 
 printf("*pm= %d\n", *pm); 
 (char*)pn = pch; 
 // pn is type cast to char* and pch is assigned to it. 
 printf("*pn= %c\n", *pn); 
 (float*)px = py; 
 printf("*px = %.3f\n", *(float*)px); 
 (char*) px = pch; 
 printf("*px = %c\n", *px); 
 (float*) pch = py; 
 printf("*pch= %.3f\n", *(float*)pch); 
} 

The output is as given below.

  

The variables n and m are of type int, while x, ch, and y are of type double, char, and float, respectively. The pointers pn and pm are of type int and are initialized with values &n and &m, respectively, while px, py, and pch are initialized by values &x, &y, and &ch, respectively. The dereferencing of the pointers gives the values of the respective variables. See lines 2 and 3 of output.

In the program pn is assigned to pm. This is valid because both are of type int. Now, value of *pm is equal to value of n because pm now points to value of n. See the fourth line of output. Next, pn is type cast to type char* and assigned the value pch. The dereferencing of pn now gives character ‘H’ which is the value of ch. Next px is type cast to type float from type double and is assigned the value py. The dereferencing of px may not display the value of y unless it is cast in printf () also. So, to get the value of y we write * (float*) px in the output statement You may get a similar problem when pch is type cast to type float. See the last line of the program. The inference is that students should be extremely careful while type casting pointers.

You’ll also like:

  1. Difference Between Type Conversion and Type Casting
  2. Explicit Type Conversion (Type Casting)
  3. Type Casting in C
  4. Type Casting in Java
  5. Type Casting in Java Example
Next →
← Prev
Like/Subscribe us for latest updates     

About Dinesh Thakur
Dinesh ThakurDinesh Thakur holds an B.C.A, MCDBA, MCSD certifications. Dinesh authors the hugely popular Computer Notes blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps.

Dinesh Thakur is a Freelance Writer who helps different clients from all over the globe. Dinesh has written over 500+ blogs, 30+ eBooks, and 10000+ Posts for all types of clients.


For any type of query or something that you think is missing, please feel free to Contact us.


Primary Sidebar

C Programming

C Programming Tutorials

  • C - History
  • C - Anatomy
  • C - Constants
  • C - Identifiers
  • C - Data Types
  • C - Libraries File
  • C - Header Files
  • C - Basic Language
  • C - Data Types Sizes
  • C - Header Files Importance
  • C - Escape Sequences
  • C - Main() Purpose
  • C - Program Procedure
  • C - Control Statements
  • C - Enumeration Constant
  • C - Add numbers
  • C - Return Statement
  • C - Avoid Goto
  • C - Command Line Arguments
  • C - Switch Case
  • C - Switch Case Limitations
  • C - getchar() and putchar()
  • C - Iteration Statements
  • C - Pass by Value and Reference
  • C - Structures and Unions
  • C - Structure
  • C - Dynamic Memory
  • C - Fgets and Fputs Functions
  • C - Gets() and Puts() Functions
  • C - Armstrong Number
  • C - Storage Classes
  • C - Fibonacci Series
  • C - Precision Setting
  • C - const Parameters

C - Variable & It's Type

  • C - Variables
  • C - Variable Lifetime
  • C - Static Variable
  • C - Register Variable
  • C - Global Variables
  • C - Auto Variables
  • C - Local Variables

C - Operator & Expressions

  • C - Operator
  • C - Boolean Operators
  • C - Bitwise Operator
  • C - Arithmetic Operators
  • C - Modulus Operator
  • C - Ternary Operator
  • C - Expressions
  • C - Arithmetic Expressions

C - Array

  • C - Arrays
  • C - Array Types
  • C - Array Characteristics
  • C - Static Arrays
  • C - Global Arrays
  • C - 3D Arrays
  • C - Dynamic Arrays
  • C - Pointer to 3D Arrays
  • C - Array Elements Hold
  • C - Arrays as Function Parameters
  • C - Accessing Matrix Elements
  • C - File Handling
  • C - Matrix Multiplication
  • C - Dynamic Memory Allocation

C - Searching & Sorting

  • C - Data Structures
  • C - Linear Search
  • C - Bubble Sort
  • C - Merge Sort
  • C - Linked List
  • C - Insertion Sort
  • C - Binary Search
  • C - Selection Sort
  • C - Quick Sort

C - Functions

  • C - Functions
  • C - Functions Advantages
  • C - Void Functions
  • C - Function Call
  • C - Default Return Value
  • C - String functions

C - Pointer

  • C - Pointers
  • C - Type Casting Of Pointers
  • C - Pointer Advantages
  • C - Pointers Initialization
  • C - Vectors and Pointers

C - Differences

  • C - C Vs C++
  • C - Formal Args. Vs Actual Args.
  • C - Keywords Vs Identifiers
  • C - Strings Vs Character Arrays
  • C - Address Vs Dereference Operator
  • C - Goto Vs longjmp
  • C - Declaring Vs Defining Variable
  • C - String Vs Array
  • C - Call by Value Vs Reference
  • C - Structure Vs Union
  • C - For Vs While loops
  • C - Compiler Vs Interpreter

C - Programs

  • C Program Standard Deviation
  • C Program Calculate Tax
  • C Program Sum Series
  • C Program Merge Arrays
  • C Program Euclid’s Algorithm
  • C Program Print Weekdays
  • C Program Sum of Digits
  • C Program Print a list
  • C Program Print Pythagorean
  • C Program Quiz program
  • C Program Display Table
  • C Program Print Comma-Separated
  • C Program Prints Prime Numbers
  • C Program for Print Integer
  • C Program Count Number
  • C Program Print Color Name
  • C Program Print Odd Numbers
  • C Program Calculate area
  • C Program for a Menu
  • C Program Add Two Vectors
  • C Program Array Addresses
  • C Program Division by Zero Error
  • C Program Compare two Dates
  • C Program Tower of Hanoi
  • C Program return 3 Numbers
  • C Program for Prime Numbers
  • C Program for Factorial
  • C Program for Palindrome

Other Links

  • C Programming - PDF Version

Footer

Basic Course

  • Computer Fundamental
  • Computer Networking
  • Operating System
  • Database System
  • Computer Graphics
  • Management System
  • Software Engineering
  • Digital Electronics
  • Electronic Commerce
  • Compiler Design
  • Troubleshooting

Programming

  • Java Programming
  • Structured Query (SQL)
  • C Programming
  • C++ Programming
  • Visual Basic
  • Data Structures
  • Struts 2
  • Java Servlet
  • C# Programming
  • Basic Terms
  • Interviews

World Wide Web

  • Internet
  • Java Script
  • HTML Language
  • Cascading Style Sheet
  • Java Server Pages
  • Wordpress
  • PHP
  • Python Tutorial
  • AngularJS
  • Troubleshooting

 About Us |  Contact Us |  FAQ

Dinesh Thakur is a Technology Columinist and founder of Computer Notes.

Copyright © 2025. All Rights Reserved.

APPLY FOR ONLINE JOB IN BIGGEST CRYPTO COMPANIES
APPLY NOW