I got an
AttributeError: '_MainProcess' object has no attribute '_exiting'
from a Python application. Unfortunately this code has to run Python 2.5 and therefore the processing module nowadays known as multiprocessing. What I was doing is to create a Process with a Queue and to put an item in the queue from the main process. Looking into the processing.queue code I can see that a feeder thread is started. This feeder thread will then check currentProcess()._exiting, but currentProcess() evaluates to a _MainProcess which does not have said attribute as can be seen in the processing.process module. How to solve this? Is it a bug in processing? If yes, can I simply monkeypatch it using currentProcess()._exiting = False?
Minimal example:
#!/usr/bin/python
import processing
import processing.queue
class Worker(processing.Process):
def __init__(self):
processing.Process.__init__(self)
self.queue = processing.queue.Q开发者_StackOverflowueue()
def run(self):
element = self.queue.get()
print element
if __name__ == '__main__':
w = Worker()
w.start()
# To trigger the problem, any non-pickleable object is to be passed here.
w.queue.put(lambda x: 1)
w.join()
I am not sure why you would want to pickle a function in this case, if you really want to do that have a look at this answer: Is there an easy way to pickle a python function (or otherwise serialize its code)?
otherwise, this works for python 2.6 (I know you are looking for 2.5 but I don't have 2.5). I have replaced your lambda function with a regular function and provide that to the processing constructor:
from multiprocessing import Process, Queue
def simple():
return 1
class Worker(Process):
def __init__(self, args):
Process.__init__(self, args=args)
self.queue = Queue()
def run(self):
element = self.queue.get()
print element
if __name__ == '__main__':
w = Worker(args=[simple])
w.start()
w.join()
加载中,请稍侯......
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