Tracevv
Tracevv((stderr, "%c", slide[w-1]));
Tracevv((stderr,"\\[%d,%d]", w-d, n));
Tracevv((stderr, "%c", slide[w-1]));
Tracevv((stderr,"%c", s->window[s->strstart-1]));
Tracevv((stderr,"%c", s->window[s->strstart-1]));
Tracevv((stderr,"%c", s->window[s->strstart]));
Tracevv((stderr," l %2d v %4x ", length, value));