# File lib/geoip.rb, line 140
  def initialize(filename, flags = 0)
    @mutex = unless IO.respond_to?(:pread)
               Mutex.new
             end

    @flags = flags
    @database_type = GEOIP_COUNTRY_EDITION
    @record_length = STANDARD_RECORD_LENGTH
    @file = File.open(filename, 'rb')

    detect_database_type!
  end