find the information about a host with the DNS retrieving system calls, such as gethostbyname() and gethostbyaddr(). (2) All the required information are in the hostent structure. (3) All the aliases and IP addresses of the host is stored i

主要用来修改DNS，一个傻瓜式的执行文件，对于系统维护人员和电脑操作一窍不通频繁做系统的人来说比较好使。-modify dns