Como buscar os detalhes do mongo db e enviar ou armazenar no objeto no método nodejs Fork

var childprocess = require('child_process');
var child = childprocess.fork(__dirname + '/child');
child.on('message', function(m) {
    // Receive results from child process
    console.log('received: ',  m);
});

var User = require('../models/User'); 
var users= {};
User.find({}, function (err, docs) {
    // Please add log in this line to check whether their is anything in database
    console.log(docs);
    debugger;
    users = docs;          
    process.send(users);              
});