- snprintf (buf, sizeof (buf), "%d", j->first);
- child->add_property (X_("in"), buf);
- snprintf (buf, sizeof (buf), "%d", j->second);
- child->add_property (X_("out"), buf);
+ child->set_property (X_("in"), j->first);
+ child->set_property (X_("out"), j->second);