function next(err) {
    if (self._extensions.length <= i) {
      return err
        ? self.onStatError(err)
        : self.error(404)
    }

    var p = path + '.' + self._extensions[i++]

    debug('stat "%s"', p)
    fs.stat(p, function (err, stat) {
      if (err) return next(err)
      if (stat.isDirectory()) return next()
      self.emit('file', p, stat)
      self.send(p, stat)
    })
  }
Transfer file for `path`.

@param {String} path
@api private