nodejs child process

//Create child process
var thread = require('child_process');

var msg = thread.fork(__dirname + '/child.js',['asdasd']);

msg.on('message', function (m) {
    debugger;
    console.log('PARENT got message:', m);
});

msg.on('close', function () {
    //3
    debugger;
})
msg.on('disconnect', function () {
    //1
    debugger;
})
msg.on('exit', function () {
//2
    debugger;
})
msg.send('asd');
setTimeout(function () {
    msg.kill();
}, 5000);

　　

child.js

process.on('message', function (m,arr) {
    setInterval(function () {
    process.exit(1);
    },2000)
});