Files
DeviceManager/node_modules/signal-exit/README.md

52 lines
1.4 KiB
Markdown

# 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`.
```js
// 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.