test.c

Linux 下 C 库及常用 系统调用的使用事例

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

int x = 0;
int y = 5;

int fun1()
{
        extern p, q;
        printf("p is %d, q is %d\n", p, q);
        return 0;
}

int p = 8;
int q = 10;

int main()
{
        fun1();
        printf("x is %d, y is %d\n", x, y);
}