signal-exit

When you want to fire an event no matter how a process exits:

reaching the end of execution.
explicitly having process.exit(code) called.
having process.kill(pid, sig) called.
receiving a fatal signal from outside the process

Use signal-exit.

// Hybrid module, either works
import { onExit } from 'signal-exit'
// or:
// const { onExit } = require('signal-exit')

onExit((code, signal) => {
  console.log('process exited!', code, signal)
})

API

remove = onExit((code, signal) => {}, options)

The return value of the function is a function that will remove the handler.

Note that the function only fires for signals if the signal would cause the process to exit. That is, there are no other listeners, and it is a fatal signal.

If the global process object is not suitable for this purpose (ie, it's unset, or doesn't have an emit method, etc.) then the onExit function is a no-op that returns a no-op remove method.

Options

alwaysLast: Run this handler after any other signal or exit handlers. This causes process.emit to be monkeypatched.

Browser Fallback

The 'signal-exit/browser' module is the same fallback shim that just doesn't do anything, but presents the same function interface.

Patches welcome to add something that hooks onto window.onbeforeunload or similar, but it might just not be a thing that makes sense there.

Current Tags

4.0.2 ... latest (21 days ago)
3.0.1 ... next (7 years ago)

signal-exit

API

Options

Browser Fallback

Current Tags

22 Versions