Node Stream bug v2

gistfile1.js

var util = require('util');
var Q = require('q');
var path = require('path');
var stream = require('stream');
var fs = require('fs');

var NullStream = function () {
    stream.Writable.call(this, { objectMode: true });
    this._write = function (data, encoding, callback) {
    };
};
util.inherits(NullStream, stream.Writable);

var streamThrough = function(filePath, done) {
    var len = 0;

    var inputStream = fs.createReadStream(filePath);
    var ps = new NullStream();

    ps.on('error', function (err) {
        done(err, len);
    });

    inputStream.on('error', function (err) {
        done(err, len);
    });

    inputStream.on('end', function () {
        console.log();
        done(null, len);
    });

    inputStream.on('data', function (chunk) {
        process.stdout.write('.');
        len += chunk.length;
    });

    inputStream.pipe(ps);
}

var fileArg = process.argv[2];
if (!fileArg) {
    console.error('pass file as arg');
    process.exit(1);
}

var filePath = path.resolve(__dirname, fileArg);

streamThrough(filePath, function(err, len) {
    if (err) {
        console.error(err.message);
    }

    console.log('size: ' + len);
})

process.on('uncaughtException', function (err) {
    console.error(err.message);
});