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Re: Why didn't my threads exit correctly ?

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Thanks for your reply, MRAB.

I've seen that the child thread has been stoped, it just died in the
queue.If I want the queue be empty, I must use queue.get() to dequeue and
clean it, but I didn't do that.
I've implement the thread using List now, thanks again.


On Fri, Oct 4, 2013 at 2:25 AM, MRAB <python@mrabarnett.plus.com> wrote:

> On 03/10/2013 18:37, 李洛 wrote:
>
>> Hi list,
>> I write an example script using threading as follow.
>> It look like hang when the list l_ip is empty. And any suggestion with
>> debug over the threading in Python ?
>>
>>    1 #!/usr/bin/env python
>>    2 # -*- coding: utf-8 -*-
>>    3 import re
>>    4 import os
>>    5 import threading
>>    6 from Queue import Queue
>>    7 from time import sleep
>>    8
>>    9 l_ip = []
>>   10 l_result = []
>>   11 result = re.compile(r"[1-3] received")
>>   12
>>   13 class ping(threading.Thread):
>>   14     """ """
>>   15     def __init__(self, l_ip, l_result):
>>   16         threading.Thread.__init__(**self)
>>   17         self.l_ip = l_ip
>>   18         #self.l_result = l_result
>>   19
>>   20     def run(self):
>>   21         """ """
>>   22         while True:
>>   23             try:
>>   24                 ip = self.l_ip.pop()
>>   25             except IndexError as e:
>>   26                 print e
>>   27                 break
>>   28             ping_out = os.popen(''.join(['ping -q -c3 ',ip]), 'r')
>>   29             print 'Ping ip:%s' % ip
>>   30             while True:
>>   31                 line = ping_out.readline()
>>   32                 if not line: break
>>   33                 if result.findall(line):
>>   34                     l_result.append(ip)
>>   35                     break
>>   36
>>   37 queue = Queue()
>>   38
>>   39 for i in range(1,110):
>>   40     l_ip.append(''.join(['192.168.**1.', str(i)]))
>>   41 for i in xrange(10):
>>   42     t = ping(l_ip, l_result)
>>   43     t.start()
>>   44     queue.put(t)
>>   45 queue.join()
>>   46 print "Result will go here."
>>   47 for i in l_result:
>>   48     print 'IP %s is OK' % i
>>
>>  queue.join() will block until the queue is empty, which is never is!
>
> You're putting the workers in the queue, whereas the normal way of
> doing it is to put them into a list, the inputs into a queue, and the
> outputs into another queue. The workers then 'get' from the input
> queue, do some processing, and 'put' to the output queue.
>
> --
> https://mail.python.org/**mailman/listinfo/python-list<https://mail.python.org/mailman/listinfo/python-list>
>



-- 
All the best!

http://luolee.me

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Re: Why didn't my threads exit correctly ? 李洛 <luolee.me@gmail.com> - 2013-10-05 00:41 +0800
  Re: Why didn't my threads exit correctly ? Piet van Oostrum <piet@vanoostrum.org> - 2013-10-05 15:22 -0400

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