TrackIter t_exit = t_iter.reverse(path);
for(unsigned i=0; i<eps.size(); ++i)
if(eps[i].track==t_exit.track() && eps[i].track_ep==t_exit.entry())
return i;
TrackIter t_exit = t_iter.reverse(path);
for(unsigned i=0; i<eps.size(); ++i)
if(eps[i].track==t_exit.track() && eps[i].track_ep==t_exit.entry())
return i;