rem: virtual void buffersize(long int samples, long int sample_rate) { if (child != 0) child->buffersize(samples, sample_rate); }
add: virtual long int buffersize(void) const { if (child != 0) return(child->buffersize()); return(0); }
context:   virtual void buffersize(long int samples, long int sample_rate) { if (child != 0) child->buffersize(samples, sample_rate); }