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

Define register simply with bit fields, Define register with bit fields? ...

Define register with bit fields? We could define register simply with bit fields: struct DISK_REGISTER { unsigned ready:1; unsigned error_occured:1; unsigned disk_spinni

Program to design list in c, Program to design list in c: Write a prog...

Program to design list in c: Write a program in c to insert the values in list void main() { int i=0; char a[20]; clrscr(); printf("Enter the line\n");

A Padovan string P(n) for a natural number n, c program for padovan string ...

c program for padovan string   Padovan series are positive integers obtained by the following process: The Padovan series is the sequence of integers P(n) defined by the

When i develop a destructor, When I develop a destructor, do I require to e...

When I develop a destructor, do I require to explicitly call the destructors for my member objects?

Programming, write a program that can accept numbers and perform all the fo...

write a program that can accept numbers and perform all the four arithmetic operation

Write a function to calculate the exchange rate, Write a function to calcul...

Write a function to calculate the exchange rate of pounds to dollars  Answer       Td = 2xTp   The parameter passed over is the number of pounds and returned the value in do

Area under curve, Write a program to find the area under the curve y = f(x)...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b.

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