#include <stdio.h>int fun1(){    printf("The first function!\n");    return 0;}int fun2(){    printf("The second function!\n");    return 0;}int fun3(){    printf("The third function!\n");    return 0;}



fun.h

#ifndef _FUN_H#define _FUN_Hextern int fun1(void);extern int fun2(void);extern int fun3(void);#endif




main.c

#include <stdio.h>#include <stdlib.h>#include "fun.h"int main(){    fun1();    fun2();    fun3();    system("pause");    return 0;}