node_reads.js

//Simple (slow) way to transfer binary data
fs.createReadStream(filepath,{'flags': 'r', 'encoding': 
                              'binary', 'mode': 0666, 'bufferSize': 64 * 1024})
  .addListener("data", function(chunk){
    res.write(chunk, 'binary');
   })
   .addListener("close",function() {
     res.close();
   })

//Faster way to transfer binary data
var chunkSize = 64 * 1024;
var bufSize   = 64 * 1024;
var bufPos    = 0;
var buf = new Buffer(bufSize);
fs.createReadStream(filepath,{'flags': 'r', 'encoding': 
                               'binary', 'mode': 0666, 'bufferSize': chunkSize})
  .addListener("data", function(chunk){
    //Since this is binary data, we cat use String.prototype.length
    //We *WANT* the number of chars, since node uses UTF-16 for bin data
    //meaning one byte bin data = one char = two bytes.
    var bufNextPos = bufPos + chunk.length;
    if (bufNextPos == bufSize) {
      buf.write(chunk,'binary',bufPos);
      res.write(buf);
      bufPos = 0;
    }
    else {
      buf.write(chunk,'binary',bufPos);
      bufPos = bufNextPos;
    }
  })
  .addListener("close",function() {
    if (bufPos != 0) {
      res.write(buf.slice(0,bufPos));
      res.end();
    }
    else
      res.close();
  })

What is res?

Hmmm, I forgot now, this was posted ages ago. I believe it was either a stream or the HTTP response.