atexit

#include<stdio.h>
#include<stdlib.h>

void exit_0();
void exit_1();


int main()
{
    atexit(exit_0);
    atexit(exit_1);
    printf("nihao\n");
    printf("world\n");

    exit(0);
}

void exit_0()
{
    printf("exit 0\n");
}

void exit_1()
{
    printf("exit 1\n");
}