You probably need to shutdown the socket nicely. See bottom of http://www.boost.org/doc/libs/1_61_0/doc/html/boost_asio/reference/basic_str... BR, Martin From: Boost-users [mailto:boost-users-bounces@lists.boost.org] On Behalf Of William Riancho Sent: Wednesday, May 18, 2016 05:25 To: boost-users@lists.boost.org Subject: [Boost-users] Blocking sockets on Windows Hello all, I try to implement a simple http server with blocking sockets on Windows. Basically, I have a simple server that just write data to a socket when a network connection occurs before exit. The problem is that the last "socket.send" as no effect if I don't delay the process exit. Writing to this socket is supposed to block until all the data as been written. I have tried to use the completion condition of write, to use the non_blocking method of the socket. I still get the same problem. Note that the problem doesn't occur on Linux. Here is the code: ``` #include <boost/asio.hpp> int main(int argc, char *argv[]) { char *address = "0.0.0.0"; char *port = "8180"; boost::asio::io_service io_service; boost::asio::ip::tcp::acceptor acceptor(io_service); boost::asio::ip::tcp::resolver resolver(io_service); boost::asio::ip::tcp::resolver::query query(address, port); boost::asio::ip::tcp::endpoint endpoint = *resolver.resolve(query); acceptor.open(endpoint.protocol()); acceptor.bind(endpoint); acceptor.listen(); boost::asio::ip::tcp::socket sock(io_service); acceptor.accept(sock); std::string body("Hello, World!"); sock.send(boost::asio::buffer(std::string("HTTP/1.1 200 OK\r\n"))); sock.send(boost::asio::buffer(std::string("Content-Length: ") + std::to_string(body.size()) + "\r\n\r\n")); sock.send(boost::asio::buffer(body)); Sleep(1000); // The body would not be sent without this return 0; } ```