logging.shutdown() ValueError: I/O operation on closed file

[j vickroy]

As a follow-up question, why is a handle object not removed from
logging._handlers when its (i.e., handle) close() procedure is applied?

That behavior appears to be responsible for the logging.shutdown() failure.


"j vickroy" <jim.vickroy at noaa.gov> wrote in message
news:bp0vaq$7lc$1 at boulder.noaa.gov...
> Hello,
>
> I'm trying to understand the behavior of the Python 2.3 logging module (MS
> Windows 2k) with regard to RotatingFileHandler.  The following script
> illustrates a puzzling problem.  What is wrong with this script?
>
> Thanks,
>
> -- jv
>
> BEGIN FILE _________________________________________
> '''
> This script terminates as follows:
>
> Traceback (most recent call last):
>   File "D:\$PROJECTS\experimental\Py Logging\t_xb.py", line 63, in ?
>     shutdown()
>   File "C:\Python23\lib\logging\__init__.py", line 1195, in shutdown
>     h.flush()
>   File "C:\Python23\lib\logging\__init__.py", line 661, in flush
>     self.stream.flush()
> ValueError: I/O operation on closed file
>
> What is wrong with it?
> '''
>
>
>
> from   logging import getLogger, Formatter, shutdown, DEBUG, INFO,
WARNING,
> ERROR, CRITICAL
> from   logging.handlers import RotatingFileHandler
>
>
>
> def logger_for(component):
>    '''
>    RETURNS a logger for the specified component.
>
>    SIDE-EFFECTS
>       (re)assigns the logger handler
>    '''
>
>    global handler
>
>    logger = getLogger(component)
>
>    if handler:
>       handler.flush()
>       handler.close()
>       logger.removeHandler(handler)
>
>    # In normal, operational mode, the following parameters:
>    filename    = '%s.log'%component
>    mode        = 'a'
>    maxBytes    = 100
>    backupCount =   5
>    # would be user-configurable "on the fly" hence the reason for this
> function.
>
>    handler = RotatingFileHandler(filename, mode, maxBytes, backupCount)
>
>    handler.setLevel(DEBUG)
>
>    logger.addHandler(handler)
>
>    return logger
>
>
>
> handler = None
>
> for i in range(20):
>    log = logger_for('supplier')
>    log.error('testing Python logging module')
>
> shutdown()
> END FILE _________________________________________
>
>