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

Hep, I need help with a c# program. Do yall help with c sharp

I need help with a c# program. Do yall help with c sharp

Described storage qualifiers in c++ ?, A: They are following: Const: poi...

A: They are following: Const: point out that memory once initialized, must not be modify through a program. Volatile: denote that value in the memory location can be modified

Explain register variable, Explain Register Variable Computers have int...

Explain Register Variable Computers have internal registers, which are used to keep data temporarily, before any operation can be performed. Intermediate results of the calcula

Make qtav videoplayer simple integrateable for application, Make QtAV Video...

Make QtAV Videoplayer simple integrateable for Qt Applications Project Description: I'm preparing an application for Windows and Mac using QtCreator. I want a videoplayer

Padovan string, write a C program for padovan string for a natural number ...

write a C program for padovan string for a natural number   program 1 : package test.padovanstring; public class PadovanString {     public int stringOccurrences(int n,

How do one throw polymorphically?, How do one throw polymorphically?       ...

How do one throw polymorphically?               A: Sometimes people write code such as: class MyExceptionBase { }; class MyExceptionDerived : public MyExceptionBase { };

However shouldn''t i always use a printon() method instead , Q: however sho...

Q: however shouldn't I always use a printOn() method instead of a friend function? A: No. The usual cause people wish to always use a printOn() method instead of  a friend fu

#title., A student apears in exam of math, physics, and chemistry. Write a...

A student apears in exam of math, physics, and chemistry. Write a program to find the total marks aa student has aqueired find the average.

Functions and stack frame, Each function has its own stack frame between %f...

Each function has its own stack frame between %fp and %sp. Let Caller calls Callee. Then Caller's %sp becomes callee's %fp, and callee's %sp set to be a new value (a smaller one be

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