const vector< shared_ptr<Signal> > sigs(_session.get_signals());
BOOST_FOREACH(shared_ptr<Signal> s, sigs) {
s->set_v_offset(offset);
const vector< shared_ptr<Signal> > sigs(_session.get_signals());
BOOST_FOREACH(shared_ptr<Signal> s, sigs) {
s->set_v_offset(offset);