Explain call by reference, C/C++ Programming

Assignment Help:

Call by Reference

Passing variables(parameters) to a function in C can be done in two ways - pass by value, also called as call by value and pass by address or also known as call by address. C++ though , gives one more way to call a function - call by reference. In call by value , a copy of the actual contents of the variables is passed to the function. In this case, alters made to the formal variable , as they are called, are not reflected back in the calling function. Passing an address permits changes to be made directly to the memory, which are occupied by the actual variable.

Though, a call by address requires the formal variable to be considered as pointer and therefore the indirection operator has to be used with them. A reference on the other hand, is another name, for a previously explained variable. In other words, after a reference is explained for a particular variable, using its original name as well as the reference can refer to the variable. Hence, a reference is nothing but an alias.

 Thus not passing a copy (call by value) saves time and is efficient. It does not have to make a temporary variable /. And not passing the address(call by address), eliminates the use of pointers in the called functions. But, at the same time, the changes made to a formal variable , using its reference or alias can be reflected back in the calling function.

 


Related Discussions:- Explain call by reference

Program to display asterisks in the shape of a plus sign, Write a program c...

Write a program called plus that will display asterisks in the shape of a plus sign which has the height and width specified by the user. You must only allow entry of an odd numb

Xmugler, #solution for decode the code for smuglers

#solution for decode the code for smuglers

Using functions create a program, In rPeANUt implement the "char getchar()"...

In rPeANUt implement the "char getchar()" and "void printstring(char *str)" functions. Using these functions implement the following: void main() {    while (1) {       ch

Padovan string, write a program that counts the number of occurrences of th...

write a program that counts the number of occurrences of the string in the n-th padovan string p(n)   program 1 : package test.padovanstring; public class PadovanString {

Last fibonnaci standing, i need a program for finding the last fibonacci nu...

i need a program for finding the last fibonacci number

Quick sort , Hi, I need quick sort program without using recursion

Hi, I need quick sort program without using recursion

Playback pattern sequences, This task involves creating a new class(es) tha...

This task involves creating a new class(es) that will allow the system to playback pattern sequences using the Neo  Freerunner  hardware. The first thing to note is that the vibrat

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd