Explain why the following Node.js (CommonJS) script works: `console.log(__dirname) console.log(process.argv)`

Question

Let the following Node.js (CommonJS) script be :

```js
console.log(__dirname)
console.log(process.argv)
```

The 3 global variables
- `console`
- `__dirname`
- and `process`

are available because...

Accepted Answer

V8 engine injects them in a script when its Javascript file is `require('xxx.js')` or launched with `node xxx.js`

Answer

they are environment variables

Answer

they are not accessible, and the script crashes

Answer

they are published across the whole process when V8 engine starts, and share the same value across all javascript files

Question from the Node.js test