dns.resolve4(hostname[, options], callback)
hostname<string> 要解析的主机名。options<Object>ttl<boolean> 检索每条记录的生存时间值 (TTL)。 当为true时,回调接收{ address: '1.2.3.4', ttl: 60 }对象数组而不是字符串数组,TTL 以秒表示。
callback<Function>err<Error>addresses<string[]> | <Object[]>
使用域名系统协议为 hostname 解析 IPv4 地址(A 记录)。
传给 callback 函数的 addresses 参数将包含 IPv4 地址的数组(例如 ['74.125.79.104', '74.125.79.105', '74.125.79.106'])。
hostname<string> Host name to resolve.options<Object>ttl<boolean> Retrieves the Time-To-Live value (TTL) of each record. Whentrue, the callback receives an array of{ address: '1.2.3.4', ttl: 60 }objects rather than an array of strings, with the TTL expressed in seconds.
callback<Function>err<Error>addresses<string[]> | <Object[]>
Uses the DNS protocol to resolve a IPv4 addresses (A records) for the
hostname. The addresses argument passed to the callback function
will contain an array of IPv4 addresses (e.g.
['74.125.79.104', '74.125.79.105', '74.125.79.106']).