Bugs item #1277903, was opened at 2005-08-31 23:49 Message generated for change (Comment added) made by alengarbage You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1277903&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: Python 2.4 Status: Open Resolution: None Priority: 5 Submitted By: Lenny G. Arbage (alengarbage) Assigned to: Vinay Sajip (vsajip) Summary: logging module broken for multiple threads? Initial Comment: After upgrading from python 2.2, I noticed that the logging facility doesn't seem to work in my code anymore. As far as I can tell, after spending a bit of time isolating the problem, this is an issue with threading. In the main thread, logging works without a hitch. In the secondary thread (which is run via twisted.reactor), any attempt to write to the log results in: Traceback (most recent call last): File "/usr/lib/python2.4/logging/__init__.py", line 712, in emit self.stream.write(fs % msg) ValueError: I/O operation on closed file The code that initializes the logger is as follows: logger = logging.getLogger('mylogger') screenhandler = logging.StreamHandler() screenhandler.setLevel(logging.INFO) logger.addHandler(self.screenhandler) logfile = "/tmp/testlog" if os.path.isfile(logfile): os.remove(logfile) handler = logging.FileHandler(logfile) formatter = logging.Formatter('%(asctime)s %(levelname)s: %(message)s') handler.setFormatter(formatter) logger.addHandler(handler) logger.setLevel(logging.INFO) Alone, this works fine. It is only when a the second thread does a 'logger = logging.getLogger('mylogger') and subsequently calls 'logger.log()' that the above error is produced. ---------------------------------------------------------------------- >Comment By: Lenny G. Arbage (alengarbage) Date: 2005-09-01 11:04 Message: Logged In: YES user_id=1338323 file attached ---------------------------------------------------------------------- Comment By: Lenny G. Arbage (alengarbage) Date: 2005-09-01 11:04 Message: Logged In: YES user_id=1338323 file attached ---------------------------------------------------------------------- Comment By: Alen Peacock (alenlpeacock) Date: 2005-09-01 11:00 Message: Logged In: YES user_id=1239721 I'm attaching a minimal program that demonstrates the behavior. You'll need twisted installed to run it. I've tested on python 2.4.1 and 2.4.14, both produce the error. ---------------------------------------------------------------------- Comment By: Raymond Hettinger (rhettinger) Date: 2005-09-01 07:54 Message: Logged In: YES user_id=80475 It looks to me like you've created a race condition that became evident only when switching Python versions. Assigning to Vijay so he can give advice on the best way to code this (most likely by moving resource competing calls to the main thread). ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1277903&group_id=5470 _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com