Advertisement

08.12.2008 at 10:40PM PDT, ID: 23643650
[x]
Attachment Details
[x]
The Solution Rating System

With so many solutions, how can you tell which solutions are most likely to help you and which ones are not? To provide you with a tool to use, we rate our solutions based on various elements that most accurately determine if a solution is a quality solution. To explain what factors affect the solution rating, here are the elements we take into consideration when formulating our solution rating.

  • The Grade of the Solution
  • The Zone Rank of the Expert Providing the Solution
  • The Number of Author and Expert Comments
  • The Number of Experts Contributing
  • The Feedback of the Community

Your Input Matters
Because of the way the system is set up, the most important variable in this equation is you. As a member of Experts Exchange, you are able to cast your vote on the quality of the solutions in regard to how complete, accurate, helpful and easy to understand each solution is. When you provide your feedback, each rating is adjusted accordingly. So, if you see a solution that has a poor rating that you think is a good solution, let us know by rating it. As you do, the rating will be adjusted and will become more accurate for other members of our site.

If you have any suggestions that you would like to make for our rating system, please ask a question in the Suggestions Zone of Community Support.

Thank you!
8.2

why children threads do not join?

Asked by summer_soccer in Python Scripting Language

Tags:

I have some code to create some child threads to do traceroute to some IP addresses. The code is attached as follows.

When the code runs, it prints

place 111111111111111111111111111111111
place 222222222222222222222222222222222222222
place 3333333333333333333333333333333333333333333333333333
place 444444444444444444444444444444444444444444444444444444444444444444

but it does not print out 'place 5'.

Why the parent process does not join?Start Free Trial 
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:

def traceroute_worker(self, q): 
        proc = q.get() 
        tracefile = proc.stdout
        while True: 
            if proc.poll() is not None: 
                break 
            sleep(5) 
            
 
    def do_traceroute(self, peers): 
 
        print 'place 111111111111111111111111111111111'
 
        q = Queue() 
 
        nump = len(peers)
 
 
        print 'place 222222222222222222222222222222222222222'
 
        if nump > 35: 
            for i in range(35): 
                t = Thread(target=self.traceroute_worker, args= (q, ))
                sleep(0.25)
                t.setDaemon(True) 
                t.start() 
        else:
            for i in range(nump): 
                t = Thread(target=self.traceroute_worker, args= (q, ))
                sleep(0.25)
                t.setDaemon(True) 
                t.start() 
 
 
        print 'place 3333333333333333333333333333333333333333333333333333'
 
        index = 0
        if os.path.isdir('./tmp/'): 
            os.system('rm -rf ./tmp/')
            #os.removedirs('./tmp/')
        os.mkdir('./tmp/')
 
        for item in peers: 
            out = open('./tmp/tmp-trace-file'+str(index), 'w')  ## convert int index to a string
            q.put(Popen(['/usr/bin/traceroute', '-n', '-z 500', item], stdout=out))
            index = index+1
 
 
        print 'place 444444444444444444444444444444444444444444444444444444444444444444'    
                    
        q.join()       # block until all tasks are done
 
        print 'place 55555555555555555555555555555555555555555555555555555555555555555555'
[+][-]08.13.2008 at 02:24AM PDT, ID: 22220192

View this solution now by starting your 7-day free trial. Setting up your free trial is quick, easy, and secure. We will return you to this solution, unlocked, when you're done.

 

About this solution

Zone: Python Scripting Language
Tags: python
Sign Up Now!
Solution Provided By: RichieHindle
Participating Experts: 1
Solution Grade: A
 
 
[+][-]08.13.2008 at 11:55AM PDT, ID: 22224492

Often, when Experts are collaborating with members who have asked questions, they will request additional information about the problem. Askers respond with an author comment like this one.

Start your 7-day free trial to view this Author Comment or ask the Experts your question.

 
 
Loading Advertisement...
20080716-EE-VQP-32 / EE_QW_2_20070628