text: //
  // posix_main.cpp
  // ~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2010 Christopher M. Kohlhoff (chris at kohlhoff dot com)
  //
  // Distributed under the Boost Software License, Version 1.0. (See accompanying
  // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  //
  
  #include <iostream>
  #include <string>
  #include <boost/asio.hpp>
  #include <boost/thread.hpp>
  #include <boost/bind.hpp>
  #include "server.hpp"
  
  #if !defined(_WIN32)
  
  #include <pthread.h>
  #include <signal.h>
  
  int main(int argc, char* argv[])
  {
    try
    {
      // Check command line arguments.
      if (argc != 4)
      {
        std::cerr << "Usage: http_server <address> <port> <doc_root>\n";
        std::cerr << "  For IPv4, try:\n";
        std::cerr << "    receiver 0.0.0.0 80 .\n";
        std::cerr << "  For IPv6, try:\n";
        std::cerr << "    receiver 0::0 80 .\n";
        return 1;
      }
  
      // Block all signals for background thread.
      sigset_t new_mask;
      sigfillset(&new_mask);
      sigset_t old_mask;
      pthread_sigmask(SIG_BLOCK, &new_mask, &old_mask);
  
      // Run server in background thread.
      http::server::server s(argv[1], argv[2], argv[3]);
      boost::thread t(boost::bind(&http::server::server::run, &s));
  
      // Restore previous signals.
      pthread_sigmask(SIG_SETMASK, &old_mask, 0);
  
      // Wait for signal indicating time to shut down.
      sigset_t wait_mask;
      sigemptyset(&wait_mask);
      sigaddset(&wait_mask, SIGINT);
      sigaddset(&wait_mask, SIGQUIT);
      sigaddset(&wait_mask, SIGTERM);
      pthread_sigmask(SIG_BLOCK, &wait_mask, 0);
      int sig = 0;
      sigwait(&wait_mask, &sig);
  
      // Stop the server.
      s.stop();
      t.join();
    }
    catch (std::exception& e)
    {
      std::cerr << "exception: " << e.what() << "\n";
    }
  
    return 0;
  }
  
  #endif // !defined(_WIN32)
  