``` using namespace std; using namespace boost::network; using namespace boost::network::http; void callback(boost::iterator_range<char const*> const &a, boost::system::error_code const &error) { if (!error) { std::string resp; resp.append(boost::begin(a), boost::end(a)); cout << resp << endl; } } int _tmain(int argc, _TCHAR* argv[]) { boost::shared_ptr<boost::asio::io_service> io_service = boost::make_shared<boost::asio::io_service>(); client::request request("http://data.video.qiyi.com/v.f4v"); client::options options; options.io_service(io_service); boost::network::string<boost::network::http::tags::http_async_8bit_udp_resolve>::type body("test"); client client(options); client::response response1 = client.post(request, body, callback); io_service->run(); // this line caused AV exception return 0; } ```