// In header: <boost/log/sinks/async_frontend.hpp>

// A scope guard that implements thread ID management.
class scoped_thread_id {
public:
  // construct/copy/destruct
  scoped_thread_id(frontend_mutex_type &, condition_variable_any &, 
                   thread::id &, boost::atomic< bool > &);
  scoped_thread_id(unique_lock< frontend_mutex_type > &, 
                   condition_variable_any &, thread::id &, 
                   boost::atomic< bool > &);
  scoped_thread_id(scoped_thread_id const &) = delete;
  scoped_thread_id & operator=(scoped_thread_id const &) = delete;
  ~scoped_thread_id();
};