端口扫描程序，输入一个特点IP和起始端口号，终止端口号，进行扫描，如果端口打开，使用函数getservbyport获取服务名，在屏幕上打印：IP port servername,如果是未知的服务，则在屏幕上显示：IP port unkown.-Port scanner, enter a starting port number and IP feature, the ending port number, scanning, if the port is open, use the function getservbyport access service, in the screen print: IP port servername, if the service is unknown, then the screen display: IP port unkown.