难道真的无法理解构造tcp :: resolver :: query的参数

我正在启动Boost.Asio并尝试在官方网站上做出示例.
这里的客户代码:

using boost::asio::ip::tcp;

int _tmain(int argc, _TCHAR* argv[])
{
    try {
        boost::asio::io_service io_service;

        tcp::resolver resolver(io_service);
        tcp::resolver::query query(argv[1], "daytime");
        tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);
        tcp::resolver::iterator end;

        tcp::socket socket(io_service);
        boost::system::error_code error = boost::asio::error::host_not_found;
        while(error && endpoint_iterator != end) {
            socket.close();
            socket.connect(*endpoint_iterator++, error);
        }
        if (error)
            throw boost::system::system_error(error);

        for(;;) {
            boost::array buf;
            boost::system::error_code error;

            std::size_t len = socket.read_some(boost::asio::buffer(buf), error);

            if (error == boost::asio::error::eof)
                break; //connection closed cleanly by peer
            else if (error)
                throw boost::system::system_error(error);

            std::cout.write(buf.data(), len);
        }
    }
    catch(std::exception& e) {
        //...
    }
    return 0;
}

问题是 - 我无法找出从命令提示符运行程序的参数是什么？

您将使用要连接的服务器的IP或主机名运行该程序.tcp :: resolver :: query使主机解析或IP作为第一个参数和服务名称(如在Unix主机上的/ etc/services中定义) - 您也可以使用数字服务标识符(也就是端口)数).它返回可能的端点列表,因为单个主机可能有多个条目.

阅读旧手册!

ip::tcp::resolver resolver(my_io_service);
ip::tcp::resolver::query query("www.boost.org", "http");
ip::tcp::resolver::iterator iter = resolver.resolve(query);
ip::tcp::resolver::iterator end; // End marker.
while (iter != end)
{
    ip::tcp::endpoint endpoint = *iter++;
    std::cout << endpoint << std::endl;
}

http://www.boost.org/doc/libs/1_38_0/doc/html/boost_asio/overview/networking/protocols.html