php实用小工具，包含1、统计在线人数（多种方法获取用户ip，优化过）2、获取服务器链接状态3、获取服务器ip，4、触发自定义函数。-php useful gadgets, including a statistical Online (a variety of methods to get the user ip, optimized) 2, to obtain server links to state 3, get the server ip, 4, triggering a custom function.