What is special about the error event?

If an EventEmitter emits error with no listener attached, Node treats it as an unhandled exception and crashes the process by throwing. Always attach an error listener to streams, sockets and servers before they can fail, even if you only log.

What is the difference between end and close on a stream?

end fires on a readable stream when there is no more data to read. close fires when the underlying resource (file descriptor, socket) has been released. A stream can emit end without close, and an errored stream may emit close without end.

Does process.exit happen automatically on uncaughtException?

If you add an uncaughtException listener the process keeps running, but the official guidance is to log, perform synchronous cleanup, then exit, because the process is in an undefined state. Without a listener Node prints the stack and exits with code 1.

When does a child_process emit exit versus close?

exit fires when the child process itself terminates, giving the exit code or signal. close fires later, once all of the child's stdio streams have been closed. close always comes after exit, so use close when you need to be sure no more output will arrive.

Is this reference searched locally?

Yes. The full event table is bundled into the page and filtered in your browser. Nothing is sent to a server.

Node.js EventEmitter Events Reference

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Node’s core APIs are event-driven

Most Node.js I/O objects extend EventEmitter and signal progress and completion by emitting named events. Knowing each event name, which object emits it, and the listener’s arguments is essential to wiring up servers, streams and processes. This reference lists the core built-in events by module.

How it works

You react to an event by registering a listener with the documented signature. The emitter calls every listener synchronously, in order, with the event’s payload arguments:

server.on("request", (req, res) => res.end("ok"));
readable.on("data", (chunk) => total += chunk.length);
readable.on("end", () => console.log("done"));
readable.on("error", (err) => console.error(err)); // always attach
child.on("exit", (code, signal) => console.log(code, signal));

Use on for repeated events and once for one-shot events. The error event is special: an unhandled error throws and crashes the process.

Tips and notes

Always attach an error listener to every stream, socket and server before use.
data is emitted only in flowing mode — calling .on("data") switches a readable stream into flowing mode.
For child processes, wait for close (not just exit) when you must be sure all stdout/stderr has been flushed.
process events like uncaughtException, unhandledRejection, SIGINT and beforeExit let you implement graceful shutdown.
Removing listeners with removeListener/off prevents leaks on long-lived emitters; watch for the MaxListenersExceededWarning.