C++ Handbook

`return` — C Keyword

`return` — C Keyword

The return keyword in C: exits the current function, optionally returning a value.

How to use this reference page

Use reference pages to confirm names, categories, nearby facilities, and the constraints that matter before writing or reviewing code.

  • Scan the top of the page first to identify the primary types, functions, or algorithm families involved.
  • Use the nearby-page links when your question is really about a companion header, related algorithm family, or broader subsystem.
  • Validate tricky behavior with a small compileable example before relying on memory for details like invalidation, ordering, allocation, or lifetime rules.

return (C)

Exits the current function. An expression may follow return to provide the return value; void functions use bare return or fall off the end.

Syntax

return;             /* void function */
return expression;  /* returns a value */

Example

#include <stdio.h>

int add(int a, int b) {
    return a + b;
}

int abs_val(int n) {
    if (n < 0) return -n;
    return n;
}

int main(void) {
    printf("%d\n", add(3, 4));     /* 7 */
    printf("%d\n", abs_val(-5));   /* 5 */
    return 0;
}

Notes

Example in practice

int main() {
    // Pick one facility from this reference page.
    // Write the smallest program that exercises its main precondition,
    // complexity rule, or lifetime constraint before scaling up.
    return 0;
}