Detecting bluetooth device disconnects/crashes

[chipimix]

Hi!
I couldn't find a way to detect if a connection has crashed or disconnected so I tried to implement my own.
In lib/connection.js, I noticed that - if I printed the chunks of the read method - they stop printing as soon as I turn off my bluetooth device; after ~20seconds of apparent frozen behavior, this method continued working, printing chunks of zero length buffers.
Thus, I added the following line
if(chunk.length == 0){ self.emit('error')}
in

(function read(){
      self.isOpen() && self.port.read((err, chunk) => {
        process.nextTick(read);
        if(err) return self.emit('error', err);
        self.emit('data', chunk);
        if(chunk.length == 0){ self.emit('error')}
      });
    })();

This allows me to fetch error events like so:

    connect(address, 1, (err, linkage) => {
      if (err) {
        console.log('connection attempt error');
      } else {
        linkage.on('error', (err) => {
          console.log('disconnected!);
        });
      }
    )}

However my approach assumes I won't be receiving zero length buffers when connected which I realize that might not always be true (or not for all devices);
Also, any thoughts on how to detect the disconnect before the ~20seconds pass?
Thanks!

[Taureon]

Wouldn't this work?

connect(address, 1, (err, linkage){
    linkage.on('end', () => {
        doStuffWhenConnectionEnds();
    });
});

(I never used node-bluetooth, this is an educational guess I made seen from similar projects)