问如何使用已关闭的ZeroMQ套接字终止进程？

EN

import zmq from 'zeromq';
import d from 'debug';

const debug = d('publisher');

let port = '8000';
let subject = 'FLIGHTS';

const socket = zmq.socket('pub');

socket.on('close', function(...toto) {
  debug('connection closed');
});
socket.on('close_error', function(...toto) {
  debug('error while closing connexion');
});

socket.monitor(10, 0);
socket.bindSync('tcp://*:' + port);

export function send(message: object) {
  const jsonMessage = JSON.stringify(message);
  socket.send([subject, jsonMessage]);
}

export function close() {
  socket.close();
}

setTimeout( () => close(), 3000 );