# File lib/core/sender.rb, line 67
    def send(message, *args)
      tag = nil
      if args.size > 0
        # deprecated: allow tag in args[0] for backwards compat
        raise ArgumentError("too many arguments") if args.size > 1
        tag = args[0]
      end
      tag ||= next_tag
      t = Tracker.new(Cproton.pn_delivery(@impl, tag))
      Cproton.pn_link_send(@impl, message.encode)
      Cproton.pn_link_advance(@impl)
      t.settle if snd_settle_mode == SND_SETTLED
      return t
    end