function lookupService
Usage in Deno
import { lookupService } from "node:dns";
lookupService(address: string,port: number,callback: (err: ErrnoException | null,hostname: string,service: string,) => void,): void
Resolves the given address
and port
into a host name and service using
the operating system's underlying getnameinfo
implementation.
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.
On an error, err
is an Error
object,
where err.code
is the error code.
const dns = require('node:dns'); dns.lookupService('127.0.0.1', 22, (err, hostname, service) => { console.log(hostname, service); // Prints: localhost ssh });
If this method is invoked as its util.promisify() ed
version, it returns a Promise
for an Object
with hostname
and service
properties.
void