// Producer/Consumer:
// Synchronisation: gemeinsamen Puffer

Buffer buffer = ....; // Operationen: push/pull
Semaphore num = 0;
Semaphore bufferAccess = 1; 

// Producer:
while (true) {
  prod = produce();
  P(bufferAccess);
  push(prod, buffer);
  V(bufferAccess);
  V(num);
}

// Consumer:
while (true) {
  P(num);
  P(bufferAccess);
  prod = pull(buffer);
  V(bufferAccess);
  consume(prod);
}