[Tutor] Threads.. help /___\ (look of despair)

[Hanna Joo]

Hi all

I wrote a simple consumer - producer program trying to use threads (solid
emphasis on 'trying'). I have this feeling I don't know how to pass
arguments to threads and keep it synchronized.. any help will be greatly
appreaciated.

import threading
from time import sleep

def producer():

 soup = 'ABCDEFGHIJKLMNOP'
 while len(buff) != 15:
  inx = randint(1,15)
  buff.append(soup[inx])
  print soup[inx], "thrown into soup!!"
  sleep(randint(1,3))

def consumer():

 while len(buff) :
  a = buff.pop()
  print a, "eaten from soup!!"
  sleep(randint(1,3))


def main():

 print 'starting threads...'
 buff = []
 firstthread = threading.Thread(target=producer, args=(buffer))       #---->
problem area!!
 secondthread = threading.Thread(target=consumer, args=(buffer)) #---->
problem area!!

 firstthread.start()
 secondthread.start()

 firstthread.join()
 secondthread.join()

if __name__ == '__main__':
 main()


ERROR>:

Exception in thread Thread-1:
Traceback (most recent call last):
  File "c:\python\lib\threading.py", line 376, in __bootstrap
    self.run()
  File "c:\python\lib\threading.py", line 364, in run
    apply(self.__target, self.__args, self.__kwargs)
TypeError: apply() 2nd argument must be a sequence

Exception in thread Thread-2:
Traceback (most recent call last):
  File "c:\python\lib\threading.py", line 376, in __bootstrap
    self.run()
  File "c:\python\lib\threading.py", line 364, in run
    apply(self.__target, self.__args, self.__kwargs)
TypeError: apply() 2nd argument must be a sequence

TIA

Hanna