type 
    buffer = 
       monitor                                     "bounded buffer monitor"
          var 
             saved: integer;                       "saved item is an integer"
             fullq, emptyq: queue;                 "used by only two processes"
             full: boolean;                        "true if an item is saved:"
          procedure entry put (item: integer);     "puts item in buffer"
             begin
                if full 
                then delay(fullq);                 "block if full"
                saved := item;                     "save the item"
                full := true;                      "mark as full"
                continue(emptyq)                   "unblock consumer"
             end;
          procedure entry get(var item: integer);  "gets item from the buffer"
             begin
                if not full 
                then delay(emptyq);                "block if empty"
                item := saved;                     "get the item"
                full := false;                     "mark as not full"
                continue(fullq)                    "unblock producer"
             end;
          begin                                    "initialize the monitor" 
             full := false 
          end;                                     
 
    producer = 
       process(pass: buffer);                      "producer uses a buffer"
          var item: integer;
          begin
             cycle                                 "execute in a loop forever"
                "produce an item"
                pass.put(item)                     "pass an item to the monitor"
             end
          end;
 
    consumer = 
       process(pass: buffer);                      "consumer uses a buffer"
          var item: integer;
          begin
             cycle                              
                pass.get(item);                    "get an item from the monitor"
                "consume the item"
             end
          end;
 
 "declare instances of the monitor, producer, and consumer"
 "give the producer and consumer access to the monitor"
 var 
    pass: buffer; 
    prod: producer; 
    cons: consumer;
 begin
    init pass,                                     "initialize the monitor"
         prod(pass),                               "start the producer process"
         cons(pass)                                "start the consumer process"
 end.