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 causesprocess.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.