Call By Value And Call By Reference In C Language

C is a powerful general-purpose programming language used to develop software like operating systems, compilers, databases, etc. Therefore, the c programme is an excellent language to learn for budding programmers. Since C is the base for other programming languages, it is basically known as the mother language. There are many concepts and methods in the c language, but many people will get confused between call by value and call by reference in c. Here is the complete guide about call by value and call by reference method in C.

Call by value in C programming

• In this parameter passing method, the formal parameter has the copied value of actual parameters. To make it simple, during the function call, the variable value is used in this call-by-value method.

• In this method, the different types of parameters are not placed in the same memory locations, so alteration done in the functions will not affect the caller's actual parameter. 

• In this method, users do not need to change the actual parameter value by formal parameter. 

• In the method of call by value, the actual parameter is used in the function call, and on the other hand, the formal parameter is used in the function definition. 

• In programming languages such as PHP, C++, and C#, the call by value is the default method. 

• In this method, the copied value is passed into the function. In call-by-value, a straightforward method is used to pass the variable value. 

Call by reference in C programming

• Here, the variable address is passed as the actual parameter into the function call.

• The same location is shared by both the formal and actual parameters. By changing the formal parameters, the actual parameter's value can be changed since the actual parameter address is passed. 

• The user can change the actual parameter's value by revamping the formal parameters.

• Pointers are necessary to store variables address in the call by reference method. Every operation in the function is implemented on the value placed at the actual parameter address, and the altered value will be placed at the same address.

• The variable itself is passed in the call by reference. It also allows the users to perform modifications in the variable's value with the help of function calls.

Also Read - Difference Between C and Java

Benefits of using call by value method

• Incall by value method, the data is preserved since the method doesn't modify the actual variable. 

• During the function call, it will not affect the original contents of the actual arguments. 

Benefits of using call by reference method

• In this method, there is no copy of the argument made, so it processes very fast. 

• It helps you to save memory space since there is no duplicate data is created. 

Closing Thoughts

In programming languages, functions are invoked only in these two methods. C programming is easier to learn than other programming languages. With the better knowledge of call by value and call by reference, it will be easier for you to implement it in your coding. 

Education Programming