title: Using TimedRotatingFileHandler logging with a logging.config
body: <p>I'm trying to test using a TimedRotatingFileHandler with a logging.config file, nothing that complicated but it should roll over every 10 seconds into a new log file.</p>
  
  <p>However I'm getting the following</p>
  
  <pre><code>Traceback (most recent call last):
    File "testLogging.py", line 6, in &lt;module&gt;
      logging.config.fileConfig(logDir+'logging.conf')
    File "C:\Python26\Lib\logging\config.py", line 84, in fileConfig
      handlers = _install_handlers(cp, formatters)
    File "C:\Python26\Lib\logging\config.py", line 159, in _install_handlers
      h = klass(*args)
    File "C:\Python26\Lib\logging\handlers.py", line 195, in __init__
      raise ValueError("You must specify a day for weekly rollover from 0 to 6 (0
  is Monday): %s" % self.when)
  ValueError: You must specify a day for weekly rollover from 0 to 6 (0 is Monday)
  : WHEN='S'
  </code></pre>
  
  <p>The python is pretty simple it just sets up an infinite loop that continually logs</p>
  
  <pre><code>import logging
  import logging.config
  
  logDir = "./logs/"
  
  logging.config.fileConfig(logDir+'logging.conf')
  logger = logging.getLogger('root')
  
  while 1==1:        
      logger.info('THIS IS AN INFO MESSAGE')
  </code></pre>
  
  <p>And the config file</p>
  
  <pre><code>[loggers]
  keys=root
  
  [logger_root]
  level=INFO
  handlers=timedRotatingFileHandler
  
  [formatters]
  keys=timedRotatingFormatter
  
  [formatter_timedRotatingFormatter]
  format=%(asctime)s %(name)-12s %(levelname)-8s %(message)s
  datefmt=%m-%d %H:%M
  
  [handlers]
  keys=timedRotatingFileHandler
  
  [handler_timedRotatingFileHandler]
  class=handlers.TimedRotatingFileHandler
  level=INFO
  formatter=timedRotatingFormatter
  args=('./logs/log.out', 'when=\'S\'', 'interval=10', 'backupCount=5')
  </code></pre>
  
  <p>As you can see when is set to 'S' not 'W' like the error message seems to indicate.</p>
  
  <p>Edit: As per the answer below the correct syntax in the logging config was</p>
  
  <pre><code>args=('./logs/log.out', 'S', 10, 5, None, False, False)
  </code></pre>