##################################################################################################
import multiprocessing
import time
import os

# PROBLEM: WHEN DEFINED HERE THEN IT IT WORKS
semaphore = multiprocessing.Semaphore(1)


def job(num, output):
  semaphore.acquire()
  time.sleep(1)
  element = "PROCESS: %d PID: %d PPID: %d" % (num, os.getpid(), os.getppid())
  print "WRITE -> " + element
  output.put(element)
  time.sleep(1)
  semaphore.release()

if __name__ == '__main__':
    """
    Reads elements as soon as they are are put inside queue
    """

    output    = multiprocessing.Manager().Queue()
    pool      = multiprocessing.Pool(4)

    # # PROBLEM: WHEN DEFINED HERE THEN IT DOES NOT WORKS
    # semaphore = multiprocessing.Semaphore(1)

    lst       = range(40)

    for i in lst:
        pool.apply_async(job, (i, output))
        print "%d Do not wait!" % i
        # res.get()

    counter = 0
    while True:
      try:
        print "READ  <- " + output.get_nowait()
        counter += 1
        if (counter == len(lst)):
          print "Break"
          break
      except:
        print "READ  <- NOTHING IN BUFFER"
        pass
      time.sleep(1)


    pool.close()
    pool.join()
##################################################################################################
# PRINT 10

global_var = 20

def print_global_var():
    print global_var

if __name__ == '__main__':
    global_var = 10
    print_global_var()
##################################################################################################