Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!ecngs!feeder2.ecngs.de!newsfeed.freenet.ag!news2.euro.net!newsgate.cistron.nl!newsgate.news.xs4all.nl!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'subject:Question': 0.07; 'wang': 0.07; 'python': 0.09; 'idea?': 0.09; 'imports': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'subject:related': 0.09; 'terminate.': 0.09; 'terry': 0.09; 'way:': 0.09; 'def': 0.10; 'advance.': 0.15; 'sat,': 0.15; 'instantiates': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'reedy': 0.16; 'run(self):': 0.16; 'win7': 0.16; 'wrote:': 0.17; 'documented': 0.17; 'module,': 0.17; 'jan': 0.18; 'windows': 0.19; 'module': 0.19; 'import': 0.21; 'skip:_ 20': 0.22; 'programming': 0.23; 'command': 0.24; 'header:In-Reply-To:1': 0.25; 'header:User-Agent:1': 0.26; 'am,': 0.27; 'header:X-Complaints-To:1': 0.28; 'chris': 0.28; 'routine': 0.29; 'starts': 0.29; 'skip:_ 10': 0.29; 'class': 0.29; "i'm": 0.29; 'print': 0.32; 'to:addr:python-list': 0.33; 'code:': 0.33; 'hi,': 0.33; 'another': 0.33; 'thanks': 0.34; 'pm,': 0.35; 'received:org': 0.36; 'but': 0.36; 'should': 0.36; 'skip:p 20': 0.36; 'keeps': 0.37; 'does': 0.37; 'why': 0.37; 'subject:: ': 0.38; 'to:addr:python.org': 0.39; 'header:Received:5': 0.40; 'think': 0.40; 'your': 0.60; "you'll": 0.62; 'protect': 0.69; 'prompt': 0.78; '2013': 0.84; 'received:fios.verizon.net': 0.84; 'repeat.': 0.84; 'rinse': 0.84 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Terry Reedy Subject: Re: Question related to multiprocessing.Process Date: Sat, 19 Jan 2013 06:27:33 -0500 References: <6816f48f-753f-4ae3-be79-3b16bd83e6f2@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: pool-173-75-251-66.phlapa.fios.verizon.net User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/17.0 Thunderbird/17.0 In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 35 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1358594886 news.xs4all.nl 6939 [2001:888:2000:d::a6]:54834 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:37081 On 1/19/2013 12:05 AM, Chris Angelico wrote: > On Sat, Jan 19, 2013 at 3:50 PM, Cen Wang wrote: >> Hi, when I use multiprocessing.Process in this way: >> >> from multiprocessing import Process >> >> class MyProcess(Process): >> >> def __init__(self): >> Process.__init__(self) >> >> def run(self): >> print 'x' >> >> p = MyProcess() >> p.start() >> >> It just keeps printing 'x' on my command prompt and does not end. But I think MyProcess should print an 'x' and then terminate. I don't why this is happening. I'm using Win7 64 bit, Python 2.7.3. Any idea? Thanks in advance. > > Multiprocessing on Windows requires that your module be importable. So > it imports your main module, which instantiates another MyProcess, > starts it, rinse and repeat. You'll need to protect your main routine > code: > > if __name__=="__main__": > p = MyProcess() > p.start() This is documented in 17.2.3. Programming guidelines 17.2.3.2. Windows -- Terry Jan Reedy