'message' 事件

• message <Object> JSON 对象或原始值。
• sendHandle <Handle> net.Socket 或 net.Server 对象，或 undefined。

当子进程使用 process.send() 发送消息时触发。

消息通过序列化和解析传递，收到的消息可能跟发送的不完全一样。

• message <Object> A parsed JSON object or primitive value.
• sendHandle <Handle> A net.Socket or net.Server object, or undefined.

The 'message' event is triggered when a child process uses process.send() to send messages.

The message goes through serialization and parsing. The resulting message might not be the same as what is originally sent.