interface audio: public handler, public Audio {
    public:
      audio();                    // Constructor (opens audioctl)
      virtual ~audio();           // Destructor  (closes audioctl)
      virtual int operator()();
  };
  

To make the functionality of audio available from Tcl scripts, add something like:

          #include <hush/kit.h>
          #include <hymne/audio.h>
          ...
          ...
          tk->action("audio", new audio());
  

hymne -- file

/dev/audioctl