DartLsl_pull_sample_buf typedef
        DartLsl_pull_sample_buf =
     double Function(lsl_inlet in$, Pointer<Pointer<Char> >  buffer, Pointer<Uint32>  buffer_lengths, int buffer_elements, double timeout, Pointer<Int32>  ec)
    
    
    
Implementation
typedef DartLsl_pull_sample_buf =
    double Function(
      lsl_inlet in$,
      ffi.Pointer<ffi.Pointer<ffi.Char>> buffer,
      ffi.Pointer<ffi.Uint32> buffer_lengths,
      int buffer_elements,
      double timeout,
      ffi.Pointer<ffi.Int32> ec,
    );