dns.lookupService(address, port, callback)

• address <string>

• port <number>

• callback <Function>

  • err <Error>

  • hostname <string> 例如 example.com

    ¥hostname <string> e.g. example.com

  • service <string> 例如 http

    ¥service <string> e.g. http

使用操作系统的底层 getnameinfo 实现将给定的 address 和 port 解析为主机名和服务。

¥Resolves the given address and port into a host name and service using the operating system's underlying getnameinfo implementation.

如果 address 不是有效的 IP 地址，则会抛出 TypeError。port 将被强制为数字。如果不是合法的端口，则会抛出 TypeError。

¥If address is not a valid IP address, a TypeError will be thrown. The port will be coerced to a number. If it is not a legal port, a TypeError will be thrown.

出错时，err 是 Error 对象，其中 err.code 是错误码。

¥On an error, err is an Error object, where err.code is the error code.

import dns from 'node:dns';
dns.lookupService('127.0.0.1', 22, (err, hostname, service) => {
  console.log(hostname, service);
  // Prints: localhost ssh
});const dns = require('node:dns');
dns.lookupService('127.0.0.1', 22, (err, hostname, service) => {
  console.log(hostname, service);
  // Prints: localhost ssh
});拷贝

如果此方法作为其 util.promisify() 版本被调用，则其将为具有 hostname 和 service 属性的 Object 返回 Promise。

¥If this method is invoked as its util.promisify()ed version, it returns a Promise for an Object with hostname and service properties.