queue check?

[ElectroLund]

Hey I really like the work you've done with this class! I looked through the documentation and can't find this... Does your class have the ability to check the serial buffer/queue for available bytes?

I'm looking to make a callback function that gets fired when there are bytes to read from the input buffer. Rather than checking the queue every N seconds and timing out, it would be more efficient to be notified when there is data to read.