process.send()

process.send(message[, sendHandle[, options]][, callback])

When Node.js is spawned with an IPC channel attached, it can send messages to its parent process using process.send(). Each will be received as a 'message' event on the parent's ChildProcess object.

Note: this function uses JSON.stringify() internally to serialize the message.

If Node.js was not spawned with an IPC channel, process.send() will be undefined.