## find attached port
	  matched = 0;
	  
	  for [comp2, comp_or_port2] = comp_S
	    for [that, that_name] = comp2
	      for [other_port, other_port_name] = that.ports
				
		if (strcmp(port_name, other_port_name)
		    && (this.index != that.index)) 
		  ## found a match ... check it is unique ...
		  if (matched == 1)
		    E = "Multiple matching vector ports: %s matches %s";
		    mtt_error(sprintf(E, port.name, other_port.name),
			      errorfile);
		  else
		    matched = 1;