# File lib/cool.io/dns_resolver.rb, line 119
    def on_readable
      datagram = nil
      begin
        datagram = @socket.recvfrom_nonblock(DATAGRAM_SIZE).first
      rescue Errno::ECONNREFUSED
      end

      address = response_address datagram rescue nil
      address ? on_success(address) : on_failure
      detach
    end