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lookupService

function lookupService
Jump to headinglookupService(
address: string,
port: number,
): Promise<{ hostname: string; service: string; }>

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 error, the Promise is rejected with an Error object, where err.code is the error code.

import dnsPromises from 'node:dns';
dnsPromises.lookupService('127.0.0.1', 22).then((result) => {
  console.log(result.hostname, result.service);
  // Prints: localhost ssh
});

Parameters Jump to heading

Jump to headingaddress: string
Jump to headingport: number

Return Type Jump to heading

Promise<{ hostname: string; service: string; }>
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