request

# File lib/resolv.rb, line 668
      def request(sender, tout)
        start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
        timelimit = start + tout
        begin
          sender.send
        rescue Errno::EHOSTUNREACH, # multi-homed IPv6 may generate this
               Errno::ENETUNREACH
          raise ResolvTimeout
        end
        while true
          before_select = Process.clock_gettime(Process::CLOCK_MONOTONIC)
          timeout = timelimit - before_select
          if timeout <= 0
            raise ResolvTimeout
          end
          if @socks.size == 1
            select_result = @socks[0].wait_readable(timeout) ? [ @socks ] : nil
          else
            select_result = IO.select(@socks, nil, nil, timeout)
          end
          if !select_result
            after_select = Process.clock_gettime(Process::CLOCK_MONOTONIC)
            next if after_select < timelimit
            raise ResolvTimeout
          end
          begin
            reply, from = recv_reply(select_result[0])
          rescue Errno::ECONNREFUSED, # GNU/Linux, FreeBSD
                 Errno::ECONNRESET # Windows
            # No name server running on the server?
            # Don't wait anymore.
            raise ResolvTimeout
          end
          begin
            msg = Message.decode(reply)
          rescue DecodeError
            next # broken DNS message ignored
          end
          if s = sender_for(from, msg)
            break
          else
            # unexpected DNS message ignored
          end
        end
        return msg, s.data
      end