我正在使用以下代码(取自 boost 教程)从服务器获取 json 字符串。
问题是它需要一些时间来执行,即超过 2 秒才能完成,并且客户端和服务器都在本地主机上。如果我删除程序的最后两行,即此时:
while (boost::asio::read(套接字,响应,
boost::asio::transfer_at_least(1),错误))
程序执行速度极快。可能是什么问题?
boost::asio::streambuf response;
boost::asio::read_until(socket, response, "\r\n");
std::istream response_stream(&response);
std::string http_version;
response_stream >> http_version;
unsigned int status_code;
response_stream >> status_code;
std::string status_message;
std::getline(response_stream, status_message);
if (!response_stream || http_version.substr(0, 5) != "HTTP/")
{
std::cout << "Invalid response\n";
return 1;
}
if (status_code != 200)
{
std::cout << "Response returned with status code " << status_code << "\n";
return 1;
}
boost::asio::read_until(socket, response, "\r\n\r\n");
// Process the response headers.
std::string header;
while (std::getline(response_stream, header) && header != "\r");
if (response.size() > 0)
std::cout << &response;
// Read until EOF, writing data to output as we go.
boost::system::error_code error;
while (boost::asio::read(socket, response,
boost::asio::transfer_at_least(1), error))
std::cout << &response;
if (error != boost::asio::error::eof)
throw boost::system::system_error(error);
tcpdump 显示来自服务器的一些数据
HTTP/1.1 200 OK
Connection: close
Content-Length: 42
Server: C/1.1
Date: Thu, 24 Nov 2016 07:47:27 GMT
{"Out":[1],"In":[1,2,3,4,5,6]}