Logging failes for rotating file log (during rollOver)

[smeyers2002]

BPO	939836
Nosy	@tim-one, @vsajip
Files	log.py: Python script that generates the descibed error

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = 'https://github.com/vsajip'
closed_at = <Date 2004-04-29.08:55:28.000>
created_at = <Date 2004-04-22.07:25:10.000>
labels = ['library']
title = 'Logging failes for rotating file log (during rollOver)'
updated_at = <Date 2004-04-29.08:55:28.000>
user = 'https://bugs.python.org/smeyers2002'

bugs.python.org fields:

activity = <Date 2004-04-29.08:55:28.000>
actor = 'smeyers2002'
assignee = 'vinay.sajip'
closed = True
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2004-04-22.07:25:10.000>
creator = 'smeyers2002'
dependencies = []
files = ['1253']
hgrepos = []
issue_num = 939836
keywords = []
message_count = 3.0
messages = ['20557', '20558', '20559']
nosy_count = 3.0
nosy_names = ['tim.peters', 'vinay.sajip', 'smeyers2002']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue939836'
versions = ['Python 2.3']

[smeyers2002]

I have a problem with the python logging. The attached
python file 'log.py' initializes the python logging (rotating
log file) and starts writing lines in a log file.

Everything works, if the line 'log.refresh' is commented
out. If the line is not commented out, I always get an
error by the first rollOver. So each time when I re-
initialize the logging (=method refresh in my code) I get
this error (see below). What can be the problem?
OS information: Windows XP Professional, version
5.1.2600 Service Pack 1

Traceback (most recent call last):
  File "log.py", line 21, in ?
    log.logger.info(" I am line "+str(i))
  File "C:\Python23\lib\logging\__init__.py", line 893, in 
info
    apply(self._log, (INFO, msg, args), kwargs)
  File "C:\Python23\lib\logging\__init__.py", line 994, in 
_log
    self.handle(record)
  File "C:\Python23\lib\logging\__init__.py", line 1004, in 
handle
    self.callHandlers(record)
  File "C:\Python23\lib\logging\__init__.py", line 1037, in 
callHandlers
    hdlr.handle(record)
  File "C:\Python23\lib\logging\__init__.py", line 592, in 
handle
    self.emit(record)
  File "C:\Python23\lib\logging\handlers.py", line 105, in 
emit
    self.doRollover()
  File "C:\Python23\lib\logging\handlers.py", line 90, in 
doRollover
    os.rename(self.baseFilename, dfn)
OSError: [Errno 13] Permission denied

---

PS: Sometimes I also get the error 'ValueError: I/O
operation on closed file'

[tim-one]

Logged In: YES
user_id=31435

Windows is unique in that it will not allow renaming (or
deleting) a file that's open. I expect that by calling refresh()
all the time, you're creating additional new objects that have
C:\log.txt open, so that it's impossible for rollover to rename
C:\log.txt on Windows. There's nothing the logging package
can do about that.

You're also adding an endless number of redundant handlers
to the same logger. Try this:

1. In your __init__ method, set

     self.logger = None

2. Start your refresh() method with

        if self.logger is not None:
            self.rotatingFileLogHandler.close()
            self.logger.removeHandler(self.rotatingFileLogHandler)

Closing the old handler arranges to close the C:\log.txt file, so
that it's *possible* to rename it on Windows. Removing the
old handler from the logger should prevent seeing an
unpredictable number of copies of individual log msgs, and
probably prevent some "I/O operation on closed file" screwups
too.

[smeyers2002]

Logged In: YES
user_id=1026630

Thanks Tim, this solved the problem.