Python Multiprocessing - How to pass kwargs to function?
keyword-argument, multiprocessing, python
Solution
When I ran your code, I got a different error:
TypeError: fp() takes at most 3 arguments (5 given)
I debugged by printing args and kwargs and changing the method to `fp(*args, **kwargs)` and noticed that "bob_" was being passed in as an array of letters. It seems that the parentheses used for `args` were operational and not actually giving you a tuple. Changing it to the list, then also passing in `numList` as a keyword argument, made the code work for me.
from multiprocessing import Process, Manager
def fp(name, numList=None, what='no'):
print ('hello %s %s' % (name, what))
numList.append(name+'44')
if __name__ == '__main__':
manager = Manager()
numList = manager.list()
for i in range(10):
keywords = {'what': 'yes', 'numList': numList}
p = Process(target=fp, args=['bob'+str(i)], kwargs=keywords)
p.start()
print("Start done")
p.join()
print("Join done")
print (numList)
Problem
How do I pass a dictionary to a function with Python's Multiprocessing? The Documentation: https://docs.python.org/3.4/library/multiprocessing.html#reference says to pass a dictionary, but I keep getting ``` TypeError: fp() got multiple values for argument 'what' ``` Here's the code: ``` from multiprocessing import Process, Manager def fp(name, numList=None, what='no'): print ('hello %s %s'% (name, what)) numList.append(name+'44') if __name__ == '__main__': manager = Manager() numList = manager.list() for i in range(10): keywords = {'what':'yes'} p = Process(target=fp, args=('bob'+str(i)), kwargs={'what':'yes'}) p.start() print("Start done") p.join() print("Join done") print (numList) ```