class SharedData
{
  // Excuted by the client process
  void calc() {
    while( somethingToCalc ) {
      // prepare data

      itsPrepared.notify_one();
      scoped_lock<interprocess_mutex> lock( itsMutex );
      itsCalced.wait( lock );

      // process results
    }
  }
  
  // Excuted by the server process
  void serverCalc() {
    while( somethingToCalc ) {
      scoped_lock<interprocess_mutex> lock( itsMutex);
      itsPrepared.wait( lock );

      // Calc

      itsRhsCalced.notify_one();
    }
  }
  

private:
  boost::interprocess::interprocess_mutex      itsMutex;

  boost::interprocess::interprocess_condition  itsPrepared;

  boost::interprocess::interprocess_condition  itsCalced;

  // some further data
};