Return Statement in C

In C programming, a function return value is the result or output produced by a function after it performs its tasks. Functions are often designed to compute or process data, and the return value allows them to communicate information back to the caller. The following function declaration declares a function called add() that takes two integers as parameters and returns their sum:

int add(int a, int b);

The return type of the add() function is int, which means that the function returns an integer value.

Function Return Value

The primary purpose of a function return value is to provide a mechanism for a function to send data or results back to the code that called it. This enables functions to contribute to the program's overall logic and allows for the reuse of computed values or outcomes.

return_type function_name(parameters) { // Function body return result; // Return value }
int add(int a, int b) { return a + b; // Returns the sum of 'a' and 'b' }

Return Type

The return type in the function declaration indicates the type of value that the function is expected to return. For example, int indicates that the function will return an integer.

Returning Values

Functions can return values of various data types, including integers, floating-point numbers, characters, and custom data types (e.g., structs).

float calculateAverage(float values[], int size) { // Calculate the average of an array of values float sum = 0.0; for (int i = 0; i < size; i++) { sum += values[i]; } return sum / size; // Returns the computed average }

Void Return

If a function does not need to return any value, its return type can be declared as void. Such functions typically perform actions or operations without producing a result.

void printMessage() { printf("Hello, world!\n"); }

Multiple Return Statements

A function can have multiple return statements, but it must return a value of the specified return type in all execution paths.

int absoluteValue(int x) { if (x < 0) { return -x; } else { return x; } }

Use of Return Values

Return values can be used in various ways, such as assigning them to variables, using them in expressions, or passing them as arguments to other functions.

int result = add(5, 3); // Store the result of the 'add' function int squared = absoluteValue(result * 2); // Use the 'absoluteValue' function


Function return values in C programming allow functions to provide results or data back to the caller. These values are specified using the return statement and play a crucial role in data processing, decision-making, and program logic. Understanding how to use and work with return values is essential for building effective and modular C programs.