# File lib/net/ssh/authentication/pageant.rb, line 325
      def send_query(query)
        res = nil
        filemap = 0
        ptr = nil
        id = Win.malloc_ptr(Win::SIZEOF_DWORD)

        mapname = "PageantRequest%08x" % Win.GetCurrentThreadId()
        security_attributes = Win.get_ptr Win.get_security_attributes_for_user

        filemap = Win.CreateFileMapping(Win::INVALID_HANDLE_VALUE,
                                        security_attributes,
                                        Win::PAGE_READWRITE, 0,
                                        AGENT_MAX_MSGLEN, mapname)

        if filemap == 0 || filemap == Win::INVALID_HANDLE_VALUE
          raise Net::SSH::Exception,
            "Creation of file mapping failed with error: #{Win.GetLastError}"
        end

        ptr = Win.MapViewOfFile(filemap, Win::FILE_MAP_WRITE, 0, 0, 
                                0)

        if ptr.nil? || ptr.null?
          raise Net::SSH::Exception, "Mapping of file failed"
        end

        Win.set_ptr_data(ptr, query)

        cds = Win.get_ptr [AGENT_COPYDATA_ID, mapname.size + 1,
                           Win.get_cstr(mapname)].pack("LLp")
        succ = Win.SendMessageTimeout(@win, Win::WM_COPYDATA, Win::NULL,
                                      cds, Win::SMTO_NORMAL, 5000, id)

        if succ > 0
          retlen = 4 + ptr.to_s(4).unpack("N")[0]
          res = ptr.to_s(retlen)
        else
          raise Net::SSH::Exception, "Message failed with error: #{Win.GetLastError}"
        end

        return res
      ensure
        Win.UnmapViewOfFile(ptr) unless ptr.nil? || ptr.null?
        Win.CloseHandle(filemap) if filemap != 0
      end