text: //
  // system_timer.hpp
  // ~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2016 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)
  //
  
  #ifndef ASIO_SYSTEM_TIMER_HPP
  #define ASIO_SYSTEM_TIMER_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include "asio/detail/config.hpp"
  
  #if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
  
  #include "asio/basic_waitable_timer.hpp"
  #include "asio/detail/chrono.hpp"
  
  namespace asio {
  
  /// Typedef for a timer based on the system clock.
  /**
   * This typedef uses the C++11 @c &lt;chrono&gt; standard library facility, if
   * available. Otherwise, it may use the Boost.Chrono library. To explicitly
   * utilise Boost.Chrono, use the basic_waitable_timer template directly:
   * @code
   * typedef basic_waitable_timer<boost::chrono::system_clock> timer;
   * @endcode
   */
  typedef basic_waitable_timer<chrono::system_clock> system_timer;
  
  } // namespace asio
  
  #endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
  
  #endif // ASIO_SYSTEM_TIMER_HPP
  