pump.js

function fastPump(source, onChunk, onError, onFinish) {
    function onRead(err, chunk) {
        if (err === true) {
            return onFinish()
        } else if (err) {
            onError(err)
        } else {
            onChunk(chunk)
        }
        
        source.read(onRead)
    }
    
    source.read(onRead)
}

stream-thing.js

var s = StreamThing()

s.read(function callback(err, chunk) {
  // read from the stream
  if (err === true) {
    // end of stream
  } else if (err) {
    // OOPS. err
  } else {
    // got a chunk
  }
})

// close the damned thing.
s.abort(function errorListener(err) {
  if (err) {
    // Something went wrong with abort
  } else {
    // successful abort
  }
})