c example for inline functions

inline_func.c

#include <stdio.h>

int fun(int x) { return x * 10; }

// inline int fun_inline(int x) { return x * 100; }   // --> causes undefined reference
extern inline int fun_inline(int x) { return x * 100; }     // ok
// static inline int fun_inline(int x) { return x * 1000; }    // ok, but this .c file local

int main(void) {
    printf("%d, %d\n", fun(2), fun_inline(2));
}
/*
20, 200

or

20, 2000
 */