global barriere 
  sem arrival = 1, departure  = 0;   int count = 0
  op barrier(val int n) 

body barriere
proc barrier (n) {
	# Ankunftsphase
	P (arrival);  count += 1
 	if (count < n) { V(arrival) } 
  else 	{ V(departure) }
	# Abgangsphase
  P(departure);  count -= 1
 	if (count > 0)  { V(departure) }
	else { V(arrival) }
  }      
end barriere