id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
3796	"""Unhandled exception"" with boost::asio library in vs2010 beta 2"	sumandeng@…	chris_kohlhoff	"I have a code snipper using boost::asio library, it runs well complied with vs2008, but occurs error compiled with vs2010 beta 2, just like this:
""Unhandled exception at 0x012ec084 in SimpleC++.exe: 0xC0000005: Access violation reading location 0x00000000.""

see code below:

#include ""stdafx.h""
#include <iostream>
#include <boost/asio.hpp>
#include <boost/array.hpp>
#include <string>

using namespace std;
using boost::asio::ip::tcp;

std::string make_header()
{
    std::string str ="""";
    str += ""GET / HTTP/1.1\n"";
    str += ""Host: www.google.com\n"";
    str += ""User-Agent: Mozilla/5.0\n"";
    str += ""Accept: */*\n"";
    str += ""Accept-Encoding: gzip,deflate\n"";
    str += ""\n\n"";

    return str;
}

int main(int argc, char* argv[])
{
    boost::asio::io_service io_service;
    tcp::resolver resolver(io_service);
    boost::asio::ip::tcp::resolver::query query(""www.google.cn"", ""http"");
    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);

    std::string message = make_header();

    cout << message << ""\n"";
    try
    {
        size_t len = socket.send(boost::asio::buffer(message));
        cout << ""send: "" << len << ""\n"";
    }
    catch (std::exception e)
    {
        cout << e.what() << std::endl;
    }
    

    size_t l = 0;
    for (;;)
    {
        boost::array<char, 256> buf;
        

        size_t len = socket.read_some(boost::asio::buffer(buf), error);
        if (error==boost::asio::error::eof)
            break;
        else if (error)
            throw boost::system::system_error(error);
        l += len;
        
        std::cout.write(buf.data(), len);

    }
    std::cout <<std::endl << l << "" bytes received.\n"";

    io_service.run();
    return 0;
} "	Bugs	closed	Boost 1.42.0	asio	Boost 1.41.0	Problem	fixed	asio, vs2010