text: //
  // detail/global.hpp
  // ~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2018 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_DETAIL_GLOBAL_HPP
  #define ASIO_DETAIL_GLOBAL_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_THREADS)
  # include "asio/detail/null_global.hpp"
  #elif defined(ASIO_WINDOWS)
  # include "asio/detail/win_global.hpp"
  #elif defined(ASIO_HAS_PTHREADS)
  # include "asio/detail/posix_global.hpp"
  #elif defined(ASIO_HAS_STD_CALL_ONCE)
  # include "asio/detail/std_global.hpp"
  #else
  # error Only Windows, POSIX and std::call_once are supported!
  #endif
  
  namespace asio {
  namespace detail {
  
  template <typename T>
  inline T& global()
  {
  #if !defined(ASIO_HAS_THREADS)
    return null_global<T>();
  #elif defined(ASIO_WINDOWS)
    return win_global<T>();
  #elif defined(ASIO_HAS_PTHREADS)
    return posix_global<T>();
  #elif defined(ASIO_HAS_STD_CALL_ONCE)
    return std_global<T>();
  #endif
  }
  
  } // namespace detail
  } // namespace asio
  
  #endif // ASIO_DETAIL_GLOBAL_HPP
  