'use strict'; const common = require('../common'); const cluster = require('cluster'); const net = require('net'); if (cluster.isPrimary) { cluster.fork().on('message', function(msg) { if (msg === 'done') this.kill(); }); } else { const server = net.createServer(common.mustNotCall()); server.listen(0, function() { server.unref(); server.ref(); server.close(function() { process.send('done'); }); }); }