Question

I tried to write stream.rdbuf() to a file but it doesn’t seem to work, just a blank file, I don`t know what to do.

#include "stdafx.h"

#include <iostream>
#include <boost/asio.hpp>
#include <conio.h>
#include <stdio.h>
#include <fstream>

char buffer [9999999];

int main()
{
    boost::asio::ip::tcp::iostream stream;
    stream.expires_from_now(boost::posix_time::seconds(60));
    stream.connect("www.mail.ru","http");
    stream << "GET / HTTP/1.1\r\n";
    stream << "Host mail.ru\r\n";
    stream << "User-Agent   Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.47 Safari/536.11\r\n";
    stream << "Accept   text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n" ;
    stream << "Accept-Encoding  gzip,deflate,sdch\r\n";
    stream << "Accept-Language  en-US,en;q=0.8\r\n";
    stream <<"Accept-Charset    ISO-8859-1,utf-8;q=0.7,*;q=0.3\r\n";
    stream << "Cookie   \r\n\r\n";
    stream.flush();
    using namespace std ;
    cout << stream.rdbuf();
    ofstream f("output.txt" /*| ios::bin*/);
    f << stream.rdbuf();
    f.close();
    system("pause");
    return 0 ;
}

Answer 1

You are invoking stream.rdbuf() twice: once for the standard out cout and then for the file.

It is unclear from your explanation whether you see anything outputed on the screen (when you write to cout).

1) If yes, you need to write that to the file instead: by the time you read the stream again, it is exhausted and does not contain anything.

Just remove the

cout << stream.rdbuf(); 

line.

If you need to see the result on the screen as well, capture it in a std::stringstream first, then you can output its content to both the screen and the file (use seekp on the stringstream to reset it after the first extraction)

2) If you do not see the results on the screen, you most likely have a problem with connecting to the service