c++ - 使用一个TCP套接字的多个请求

Question

我正在学习套接字编程(和C++)。我写了一个下面的函数，要求一个数组的总和(使用boost库):

std::future<void> AsyncClient::ReqSum(const std::vector<double>& numbers)
{
    return std::async(
        std::launch::async,
        [&, numbers]()
        {
            // Setup connection.
            boost::asio::io_service _ioservice;
            tcp::socket _socket(_ioservice);
            _socket.connect(m_endpoint);

            std::string requestJson = Serializer::ArraySumRequest(numbers);
            boost::system::error_code err;
            while (true)
            {
                boost::asio::write(_socket, boost::asio::buffer(requestJson), err);
                if (err)
                {
                    std::stringstream ss;
                    ss << "Couldn't write to socket! error code: " << err;
                    throw ss.str();
                }

                // getting response from server
                boost::asio::streambuf receiveBuffer;
                boost::asio::read(_socket, receiveBuffer, boost::asio::transfer_all(), err);

                if (err && err != boost::asio::error::eof)
                {
                    std::stringstream ss;
                    ss << "Receiving from the server failed! error code: " << err.message();
                    throw ss.str();
                }

                const char* data = boost::asio::buffer_cast<const char*>(receiveBuffer.data());

                rapidjson::Document doc;
                doc.Parse<rapidjson::kParseDefaultFlags>(data);

                if (!doc.HasMember("result"))
                    throw "No result found!";

                double result = doc["result"].GetDouble();

                std::cout << "Sum of the array: " << result << std::endl;
            }
            _socket.shutdown(boost::asio::socket_base::shutdown_both);
            _socket.close();
        });
}

第一次写入和读取都可以正常工作，但是第二次进入循环写入套接字可以正常工作，但是读取时出现错误:

error code: 10053; message: An established connection was aborted by the software in your machine host.

此错误与我的机器有关吗？我应该怎么做才能做到这一点？

Answer 1

您似乎正在尝试从服务器接收所有数据:

boost::asio::streambuf receiveBuffer;
boost::asio::read(_socket, receiveBuffer, boost::asio::transfer_all(), err);

read()命令完成的唯一方法是服务器指示流的结尾。由于您是第一次收到有效的响应，这意味着服务器在向您发送响应后立即关闭了连接。