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

Flow chart, how made a flow chart of prime number by using for loop

how made a flow chart of prime number by using for loop

Define commonly used built-in library functions, Define Commonly Used Built...

Define Commonly Used Built-in Library Functions? Comprise opened a file pointer you will desire to use it for either input or output. The C language supplies a set of functions

Recursive function, Write a recursive function recursiveMin that takes an i...

Write a recursive function recursiveMin that takes an integer array, a starting subscript and an ending subscript as arguments, and returns the smallest element in the array. The f

Flow chart, obtain two numbers from thekey board,and determain and display(...

obtain two numbers from thekey board,and determain and display(if either)is the larger of two numbers.

B tree, real time application of b tree

real time application of b tree

Give example of the do while loop, Normal 0 false false fal...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Define bitwise left shift and right shift operators, Define Bitwise Left Sh...

Define Bitwise Left Shift and Right Shift Operators: >? The bitwise shift operators shift their first operand right (>>) or left ( // Illustration of the bitwise right shi

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