--- rest25/library/logging.rst	2008-12-19 16:58:07.000000000 +0900
+++ rest262/library/logging.rst	2009-04-05 05:02:09.000000000 +0900
@@ -1,50 +1,481 @@
-
 :mod:`logging` --- Logging facility for Python
 ==============================================
 
 .. module:: logging
+   :synopsis: Flexible error logging system for applications.
 
 
 .. moduleauthor:: Vinay Sajip <vinay_sajip@red-dove.com>
 .. sectionauthor:: Vinay Sajip <vinay_sajip@red-dove.com>
 
 
-.. % These apply to all modules, and may be given more than once:
-
-
-
 .. index:: pair: Errors; logging
 
 .. versionadded:: 2.3
 
 This module defines functions and classes which implement a flexible error
 logging system for applications.
 
 Logging is performed by calling methods on instances of the :class:`Logger`
 class (hereafter called :dfn:`loggers`). Each instance has a name, and they are
-conceptually arranged in a name space hierarchy using dots (periods) as
+conceptually arranged in a namespace hierarchy using dots (periods) as
 separators. For example, a logger named "scan" is the parent of loggers
 "scan.text", "scan.html" and "scan.pdf". Logger names can be anything you want,
 and indicate the area of an application in which a logged message originates.
 
 Logged messages also have levels of importance associated with them. The default
 levels provided are :const:`DEBUG`, :const:`INFO`, :const:`WARNING`,
 :const:`ERROR` and :const:`CRITICAL`. As a convenience, you indicate the
 importance of a logged message by calling an appropriate method of
 :class:`Logger`. The methods are :meth:`debug`, :meth:`info`, :meth:`warning`,
 :meth:`error` and :meth:`critical`, which mirror the default levels. You are not
 constrained to use these levels: you can specify your own and use a more general
 :class:`Logger` method, :meth:`log`, which takes an explicit level argument.
 
+
+Logging tutorial
+----------------
+
+The key benefit of having the logging API provided by a standard library module
+is that all Python modules can participate in logging, so your application log
+can include messages from third-party modules.
+
+It is, of course, possible to log messages with different verbosity levels or to
+different destinations.  Support for writing log messages to files, HTTP
+GET/POST locations, email via SMTP, generic sockets, or OS-specific logging
+mechanisms are all supported by the standard module.  You can also create your
+own log destination class if you have special requirements not met by any of the
+built-in classes.
+
+Simple examples
+^^^^^^^^^^^^^^^
+
+.. sectionauthor:: Doug Hellmann
+.. (see <http://blog.doughellmann.com/2007/05/pymotw-logging.html>)
+
+Most applications are probably going to want to log to a file, so let's start
+with that case. Using the :func:`basicConfig` function, we can set up the
+default handler so that debug messages are written to a file::
+
+   import logging
+   LOG_FILENAME = '/tmp/logging_example.out'
+   logging.basicConfig(filename=LOG_FILENAME,level=logging.DEBUG,)
+
+   logging.debug('This message should go to the log file')
+
+And now if we open the file and look at what we have, we should find the log
+message::
+
+   DEBUG:root:This message should go to the log file
+
+If you run the script repeatedly, the additional log messages are appended to
+the file.  To create a new file each time, you can pass a filemode argument to
+:func:`basicConfig` with a value of ``'w'``.  Rather than managing the file size
+yourself, though, it is simpler to use a :class:`RotatingFileHandler`::
+
+   import glob
+   import logging
+   import logging.handlers
+
+   LOG_FILENAME = '/tmp/logging_rotatingfile_example.out'
+
+   # Set up a specific logger with our desired output level
+   my_logger = logging.getLogger('MyLogger')
+   my_logger.setLevel(logging.DEBUG)
+
+   # Add the log message handler to the logger
+   handler = logging.handlers.RotatingFileHandler(
+                 LOG_FILENAME, maxBytes=20, backupCount=5)
+
+   my_logger.addHandler(handler)
+
+   # Log some messages
+   for i in range(20):
+       my_logger.debug('i = %d' % i)
+
+   # See what files are created
+   logfiles = glob.glob('%s*' % LOG_FILENAME)
+
+   for filename in logfiles:
+       print filename
+
+The result should be 6 separate files, each with part of the log history for the
+application::
+
+   /tmp/logging_rotatingfile_example.out
+   /tmp/logging_rotatingfile_example.out.1
+   /tmp/logging_rotatingfile_example.out.2
+   /tmp/logging_rotatingfile_example.out.3
+   /tmp/logging_rotatingfile_example.out.4
+   /tmp/logging_rotatingfile_example.out.5
+
+The most current file is always :file:`/tmp/logging_rotatingfile_example.out`,
+and each time it reaches the size limit it is renamed with the suffix
+``.1``. Each of the existing backup files is renamed to increment the suffix
+(``.1`` becomes ``.2``, etc.)  and the ``.5`` file is erased.
+
+Obviously this example sets the log length much much too small as an extreme
+example.  You would want to set *maxBytes* to an appropriate value.
+
+Another useful feature of the logging API is the ability to produce different
+messages at different log levels.  This allows you to instrument your code with
+debug messages, for example, but turning the log level down so that those debug
+messages are not written for your production system.  The default levels are
+``CRITICAL``, ``ERROR``, ``WARNING``, ``INFO``, ``DEBUG`` and ``NOTSET``.
+
+The logger, handler, and log message call each specify a level.  The log message
+is only emitted if the handler and logger are configured to emit messages of
+that level or lower.  For example, if a message is ``CRITICAL``, and the logger
+is set to ``ERROR``, the message is emitted.  If a message is a ``WARNING``, and
+the logger is set to produce only ``ERROR``\s, the message is not emitted::
+
+   import logging
+   import sys
+
+   LEVELS = {'debug': logging.DEBUG,
+             'info': logging.INFO,
+             'warning': logging.WARNING,
+             'error': logging.ERROR,
+             'critical': logging.CRITICAL}
+
+   if len(sys.argv) > 1:
+       level_name = sys.argv[1]
+       level = LEVELS.get(level_name, logging.NOTSET)
+       logging.basicConfig(level=level)
+
+   logging.debug('This is a debug message')
+   logging.info('This is an info message')
+   logging.warning('This is a warning message')
+   logging.error('This is an error message')
+   logging.critical('This is a critical error message')
+
+Run the script with an argument like 'debug' or 'warning' to see which messages
+show up at different levels::
+
+   $ python logging_level_example.py debug
+   DEBUG:root:This is a debug message
+   INFO:root:This is an info message
+   WARNING:root:This is a warning message
+   ERROR:root:This is an error message
+   CRITICAL:root:This is a critical error message
+
+   $ python logging_level_example.py info
+   INFO:root:This is an info message
+   WARNING:root:This is a warning message
+   ERROR:root:This is an error message
+   CRITICAL:root:This is a critical error message
+
+You will notice that these log messages all have ``root`` embedded in them.  The
+logging module supports a hierarchy of loggers with different names.  An easy
+way to tell where a specific log message comes from is to use a separate logger
+object for each of your modules.  Each new logger "inherits" the configuration
+of its parent, and log messages sent to a logger include the name of that
+logger.  Optionally, each logger can be configured differently, so that messages
+from different modules are handled in different ways.  Let's look at a simple
+example of how to log from different modules so it is easy to trace the source
+of the message::
+
+   import logging
+
+   logging.basicConfig(level=logging.WARNING)
+
+   logger1 = logging.getLogger('package1.module1')
+   logger2 = logging.getLogger('package2.module2')
+
+   logger1.warning('This message comes from one module')
+   logger2.warning('And this message comes from another module')
+
+And the output::
+
+   $ python logging_modules_example.py
+   WARNING:package1.module1:This message comes from one module
+   WARNING:package2.module2:And this message comes from another module
+
+There are many more options for configuring logging, including different log
+message formatting options, having messages delivered to multiple destinations,
+and changing the configuration of a long-running application on the fly using a
+socket interface.  All of these options are covered in depth in the library
+module documentation.
+
+Loggers
+^^^^^^^
+
+The logging library takes a modular approach and offers the several categories
+of components: loggers, handlers, filters, and formatters.  Loggers expose the
+interface that application code directly uses.  Handlers send the log records to
+the appropriate destination. Filters provide a finer grained facility for
+determining which log records to send on to a handler.  Formatters specify the
+layout of the resultant log record.
+
+:class:`Logger` objects have a threefold job.  First, they expose several
+methods to application code so that applications can log messages at runtime.
+Second, logger objects determine which log messages to act upon based upon
+severity (the default filtering facility) or filter objects.  Third, logger
+objects pass along relevant log messages to all interested log handlers.
+
+The most widely used methods on logger objects fall into two categories:
+configuration and message sending.
+
+* :meth:`Logger.setLevel` specifies the lowest-severity log message a logger
+  will handle, where debug is the lowest built-in severity level and critical is
+  the highest built-in severity.  For example, if the severity level is info,
+  the logger will handle only info, warning, error, and critical messages and
+  will ignore debug messages.
+
+* :meth:`Logger.addFilter` and :meth:`Logger.removeFilter` add and remove filter
+  objects from the logger object.  This tutorial does not address filters.
+
+With the logger object configured, the following methods create log messages:
+
+* :meth:`Logger.debug`, :meth:`Logger.info`, :meth:`Logger.warning`,
+  :meth:`Logger.error`, and :meth:`Logger.critical` all create log records with
+  a message and a level that corresponds to their respective method names. The
+  message is actually a format string, which may contain the standard string
+  substitution syntax of :const:`%s`, :const:`%d`, :const:`%f`, and so on.  The
+  rest of their arguments is a list of objects that correspond with the
+  substitution fields in the message.  With regard to :const:`**kwargs`, the
+  logging methods care only about a keyword of :const:`exc_info` and use it to
+  determine whether to log exception information.
+
+* :meth:`Logger.exception` creates a log message similar to
+  :meth:`Logger.error`.  The difference is that :meth:`Logger.exception` dumps a
+  stack trace along with it.  Call this method only from an exception handler.
+
+* :meth:`Logger.log` takes a log level as an explicit argument.  This is a
+  little more verbose for logging messages than using the log level convenience
+  methods listed above, but this is how to log at custom log levels.
+
+:func:`getLogger` returns a reference to a logger instance with the specified
+if it it is provided, or ``root`` if not.  The names are period-separated
+hierarchical structures.  Multiple calls to :func:`getLogger` with the same name
+will return a reference to the same logger object.  Loggers that are further
+down in the hierarchical list are children of loggers higher up in the list.
+For example, given a logger with a name of ``foo``, loggers with names of
+``foo.bar``, ``foo.bar.baz``, and ``foo.bam`` are all children of ``foo``.
+Child loggers propagate messages up to their parent loggers.  Because of this,
+it is unnecessary to define and configure all the loggers an application uses.
+It is sufficient to configure a top-level logger and create child loggers as
+needed.
+
+
+Handlers
+^^^^^^^^
+
+:class:`Handler` objects are responsible for dispatching the appropriate log
+messages (based on the log messages' severity) to the handler's specified
+destination.  Logger objects can add zero or more handler objects to themselves
+with an :func:`addHandler` method.  As an example scenario, an application may
+want to send all log messages to a log file, all log messages of error or higher
+to stdout, and all messages of critical to an email address.  This scenario
+requires three individual handlers where each handler is responsible for sending
+messages of a specific severity to a specific location.
+
+The standard library includes quite a few handler types; this tutorial uses only
+:class:`StreamHandler` and :class:`FileHandler` in its examples.
+
+There are very few methods in a handler for application developers to concern
+themselves with.  The only handler methods that seem relevant for application
+developers who are using the built-in handler objects (that is, not creating
+custom handlers) are the following configuration methods:
+
+* The :meth:`Handler.setLevel` method, just as in logger objects, specifies the
+  lowest severity that will be dispatched to the appropriate destination.  Why
+  are there two :func:`setLevel` methods?  The level set in the logger
+  determines which severity of messages it will pass to its handlers.  The level
+  set in each handler determines which messages that handler will send on.
+  :func:`setFormatter` selects a Formatter object for this handler to use.
+
+* :func:`addFilter` and :func:`removeFilter` respectively configure and
+  deconfigure filter objects on handlers.
+
+Application code should not directly instantiate and use handlers.  Instead, the
+:class:`Handler` class is a base class that defines the interface that all
+Handlers should have and establishes some default behavior that child classes
+can use (or override).
+
+
+Formatters
+^^^^^^^^^^
+
+Formatter objects configure the final order, structure, and contents of the log
+message.  Unlike the base :class:`logging.Handler` class, application code may
+instantiate formatter classes, although you could likely subclass the formatter
+if your application needs special behavior.  The constructor takes two optional
+arguments: a message format string and a date format string.  If there is no
+message format string, the default is to use the raw message.  If there is no
+date format string, the default date format is::
+
+    %Y-%m-%d %H:%M:%S
+
+with the milliseconds tacked on at the end.
+
+The message format string uses ``%(<dictionary key>)s`` styled string
+substitution; the possible keys are documented in :ref:`formatter-objects`.
+
+The following message format string will log the time in a human-readable
+format, the severity of the message, and the contents of the message, in that
+order::
+
+    "%(asctime)s - %(levelname)s - %(message)s"
+
+
+Configuring Logging
+^^^^^^^^^^^^^^^^^^^
+
+Programmers can configure logging either by creating loggers, handlers, and
+formatters explicitly in a main module with the configuration methods listed
+above (using Python code), or by creating a logging config file.  The following
+code is an example of configuring a very simple logger, a console handler, and a
+simple formatter in a Python module::
+
+    import logging
+
+    # create logger
+    logger = logging.getLogger("simple_example")
+    logger.setLevel(logging.DEBUG)
+    # create console handler and set level to debug
+    ch = logging.StreamHandler()
+    ch.setLevel(logging.DEBUG)
+    # create formatter
+    formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+    # add formatter to ch
+    ch.setFormatter(formatter)
+    # add ch to logger
+    logger.addHandler(ch)
+
+    # "application" code
+    logger.debug("debug message")
+    logger.info("info message")
+    logger.warn("warn message")
+    logger.error("error message")
+    logger.critical("critical message")
+
+Running this module from the command line produces the following output::
+
+    $ python simple_logging_module.py
+    2005-03-19 15:10:26,618 - simple_example - DEBUG - debug message
+    2005-03-19 15:10:26,620 - simple_example - INFO - info message
+    2005-03-19 15:10:26,695 - simple_example - WARNING - warn message
+    2005-03-19 15:10:26,697 - simple_example - ERROR - error message
+    2005-03-19 15:10:26,773 - simple_example - CRITICAL - critical message
+
+The following Python module creates a logger, handler, and formatter nearly
+identical to those in the example listed above, with the only difference being
+the names of the objects::
+
+    import logging
+    import logging.config
+
+    logging.config.fileConfig("logging.conf")
+
+    # create logger
+    logger = logging.getLogger("simpleExample")
+
+    # "application" code
+    logger.debug("debug message")
+    logger.info("info message")
+    logger.warn("warn message")
+    logger.error("error message")
+    logger.critical("critical message")
+
+Here is the logging.conf file::
+
+    [loggers]
+    keys=root,simpleExample
+
+    [handlers]
+    keys=consoleHandler
+
+    [formatters]
+    keys=simpleFormatter
+
+    [logger_root]
+    level=DEBUG
+    handlers=consoleHandler
+
+    [logger_simpleExample]
+    level=DEBUG
+    handlers=consoleHandler
+    qualname=simpleExample
+    propagate=0
+
+    [handler_consoleHandler]
+    class=StreamHandler
+    level=DEBUG
+    formatter=simpleFormatter
+    args=(sys.stdout,)
+
+    [formatter_simpleFormatter]
+    format=%(asctime)s - %(name)s - %(levelname)s - %(message)s
+    datefmt=
+
+The output is nearly identical to that of the non-config-file-based example::
+
+    $ python simple_logging_config.py
+    2005-03-19 15:38:55,977 - simpleExample - DEBUG - debug message
+    2005-03-19 15:38:55,979 - simpleExample - INFO - info message
+    2005-03-19 15:38:56,054 - simpleExample - WARNING - warn message
+    2005-03-19 15:38:56,055 - simpleExample - ERROR - error message
+    2005-03-19 15:38:56,130 - simpleExample - CRITICAL - critical message
+
+You can see that the config file approach has a few advantages over the Python
+code approach, mainly separation of configuration and code and the ability of
+noncoders to easily modify the logging properties.
+
+.. _library-config:
+
+Configuring Logging for a Library
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+When developing a library which uses logging, some consideration needs to be
+given to its configuration. If the using application does not use logging, and
+library code makes logging calls, then a one-off message "No handlers could be
+found for logger X.Y.Z" is printed to the console. This message is intended
+to catch mistakes in logging configuration, but will confuse an application
+developer who is not aware of logging by the library.
+
+In addition to documenting how a library uses logging, a good way to configure
+library logging so that it does not cause a spurious message is to add a
+handler which does nothing. This avoids the message being printed, since a
+handler will be found: it just doesn't produce any output. If the library user
+configures logging for application use, presumably that configuration will add
+some handlers, and if levels are suitably configured then logging calls made
+in library code will send output to those handlers, as normal.
+
+A do-nothing handler can be simply defined as follows::
+
+    import logging
+
+    class NullHandler(logging.Handler):
+        def emit(self, record):
+            pass
+
+An instance of this handler should be added to the top-level logger of the
+logging namespace used by the library. If all logging by a library *foo* is
+done using loggers with names matching "foo.x.y", then the code::
+
+    import logging
+
+    h = NullHandler()
+    logging.getLogger("foo").addHandler(h)
+
+should have the desired effect. If an organisation produces a number of
+libraries, then the logger name specified can be "orgname.foo" rather than
+just "foo".
+
+
+Logging Levels
+--------------
+
 The numeric values of logging levels are given in the following table. These are
 primarily of interest if you want to define your own levels, and need them to
 have specific values relative to the predefined levels. If you define a level
 with the same numeric value, it overwrites the predefined value; the predefined
 name is lost.
 
 +--------------+---------------+
 | Level        | Numeric value |
 +==============+===============+
 | ``CRITICAL`` | 50            |
 +--------------+---------------+
 | ``ERROR``    | 40            |
@@ -86,57 +517,63 @@
 decides to actually dispatch an event, the :meth:`emit` method is used to send
 the message to its destination. Most user-defined subclasses of :class:`Handler`
 will need to override this :meth:`emit`.
 
 In addition to the base :class:`Handler` class, many useful subclasses are
 provided:
 
 #. :class:`StreamHandler` instances send error messages to streams (file-like
    objects).
 
 #. :class:`FileHandler` instances send error messages to disk files.
 
-#. :class:`BaseRotatingHandler` is the base class for handlers that rotate log
-   files at a certain point. It is not meant to be  instantiated directly. Instead,
-   use :class:`RotatingFileHandler` or :class:`TimedRotatingFileHandler`.
+#. :class:`handlers.BaseRotatingHandler` is the base class for handlers that
+   rotate log files at a certain point. It is not meant to be  instantiated
+   directly. Instead, use :class:`RotatingFileHandler` or
+   :class:`TimedRotatingFileHandler`.
 
-#. :class:`RotatingFileHandler` instances send error messages to disk files,
+#. :class:`handlers.RotatingFileHandler` instances send error messages to disk files,
    with support for maximum log file sizes and log file rotation.
 
-#. :class:`TimedRotatingFileHandler` instances send error messages to disk files
+#. :class:`handlers.TimedRotatingFileHandler` instances send error messages to disk files
    rotating the log file at certain timed intervals.
 
-#. :class:`SocketHandler` instances send error messages to TCP/IP sockets.
+#. :class:`handlers.SocketHandler` instances send error messages to TCP/IP sockets.
 
-#. :class:`DatagramHandler` instances send error messages to UDP sockets.
+#. :class:`handlers.DatagramHandler` instances send error messages to UDP sockets.
 
-#. :class:`SMTPHandler` instances send error messages to a designated email
+#. :class:`handlers.SMTPHandler` instances send error messages to a designated email
    address.
 
-#. :class:`SysLogHandler` instances send error messages to a Unix syslog daemon,
+#. :class:`handlers.SysLogHandler` instances send error messages to a Unix syslog daemon,
    possibly on a remote machine.
 
-#. :class:`NTEventLogHandler` instances send error messages to a Windows
+#. :class:`handlers.NTEventLogHandler` instances send error messages to a Windows
    NT/2000/XP event log.
 
-#. :class:`MemoryHandler` instances send error messages to a buffer in memory,
+#. :class:`handlers.MemoryHandler` instances send error messages to a buffer in memory,
    which is flushed whenever specific criteria are met.
 
-#. :class:`HTTPHandler` instances send error messages to an HTTP server using
+#. :class:`handlers.HTTPHandler` instances send error messages to an HTTP server using
    either ``GET`` or ``POST`` semantics.
 
-The :class:`StreamHandler` and :class:`FileHandler` classes are defined in the
-core logging package. The other handlers are defined in a sub- module,
-:mod:`logging.handlers`. (There is also another sub-module,
-:mod:`logging.config`, for configuration functionality.)
+#. :class:`handlers.WatchedFileHandler` instances watch the file they are logging to. If
+the file changes, it is closed and reopened using the file name. This handler
+is only useful on Unix-like systems; Windows does not support the underlying
+mechanism used.
+
+The :class:`StreamHandler` and :class:`FileHandler`
+classes are defined in the core logging package. The other handlers are
+defined in a sub- module, :mod:`logging.handlers`. (There is also another
+sub-module, :mod:`logging.config`, for configuration functionality.)
 
 Logged messages are formatted for presentation through instances of the
 :class:`Formatter` class. They are initialized with a format string suitable for
 use with the % operator and a dictionary.
 
 For formatting multiple messages in a batch, instances of
 :class:`BufferingFormatter` can be used. In addition to the format string (which
 is applied to each message in the batch), there is provision for header and
 trailer format strings.
 
 When filtering based on logger level and/or handler level is not enough,
 instances of :class:`Filter` can be added to both :class:`Logger` and
@@ -188,25 +625,25 @@
    added to the logging message. If an exception tuple (in the format returned by
    :func:`sys.exc_info`) is provided, it is used; otherwise, :func:`sys.exc_info`
    is called to get the exception information.
 
    The other optional keyword argument is *extra* which can be used to pass a
    dictionary which is used to populate the __dict__ of the LogRecord created for
    the logging event with user-defined attributes. These custom attributes can then
    be used as you like. For example, they could be incorporated into logged
    messages. For example::
 
       FORMAT = "%(asctime)-15s %(clientip)s %(user)-8s %(message)s"
       logging.basicConfig(format=FORMAT)
-      dict = { 'clientip' : '192.168.0.1', 'user' : 'fbloggs' }
+      d = {'clientip': '192.168.0.1', 'user': 'fbloggs'}
       logging.warning("Protocol problem: %s", "connection reset", extra=d)
 
    would print something like  ::
 
       2006-02-08 22:20:02,165 192.168.0.1 fbloggs  Protocol problem: connection reset
 
    The keys in the dictionary passed in *extra* should not clash with the keys used
    by the logging system. (See the :class:`Formatter` documentation for more
    information on which keys are used by the logging system.)
 
    If you choose to use these attributes in logged messages, you need to exercise
    some care. In the above example, for instance, the :class:`Formatter` has been
@@ -294,28 +731,31 @@
 .. function:: makeLogRecord(attrdict)
 
    Creates and returns a new :class:`LogRecord` instance whose attributes are
    defined by *attrdict*. This function is useful for taking a pickled
    :class:`LogRecord` attribute dictionary, sent over a socket, and reconstituting
    it as a :class:`LogRecord` instance at the receiving end.
 
 
 .. function:: basicConfig([**kwargs])
 
    Does basic configuration for the logging system by creating a
    :class:`StreamHandler` with a default :class:`Formatter` and adding it to the
-   root logger. The functions :func:`debug`, :func:`info`, :func:`warning`,
+   root logger. The function does nothing if any handlers have been defined for
+   the root logger. The functions :func:`debug`, :func:`info`, :func:`warning`,
    :func:`error` and :func:`critical` will call :func:`basicConfig` automatically
    if no handlers are defined for the root logger.
 
+   This function does nothing if the root logger already has handlers configured.
+
    .. versionchanged:: 2.4
       Formerly, :func:`basicConfig` did not take any keyword arguments.
 
    The following keyword arguments are supported.
 
    +--------------+---------------------------------------------+
    | Format       | Description                                 |
    +==============+=============================================+
    | ``filename`` | Specifies that a FileHandler be created,    |
    |              | using the specified filename, rather than a |
    |              | StreamHandler.                              |
    +--------------+---------------------------------------------+
@@ -332,122 +772,123 @@
    |              | level.                                      |
    +--------------+---------------------------------------------+
    | ``stream``   | Use the specified stream to initialize the  |
    |              | StreamHandler. Note that this argument is   |
    |              | incompatible with 'filename' - if both are  |
    |              | present, 'stream' is ignored.               |
    +--------------+---------------------------------------------+
 
 
 .. function:: shutdown()
 
    Informs the logging system to perform an orderly shutdown by flushing and
-   closing all handlers.
+   closing all handlers. This should be called at application exit and no
+   further use of the logging system should be made after this call.
 
 
 .. function:: setLoggerClass(klass)
 
    Tells the logging system to use the class *klass* when instantiating a logger.
    The class should define :meth:`__init__` such that only a name argument is
    required, and the :meth:`__init__` should call :meth:`Logger.__init__`. This
    function is typically called before any loggers are instantiated by applications
    which need to use custom logger behavior.
 
 
 .. seealso::
 
    :pep:`282` - A Logging System
       The proposal which described this feature for inclusion in the Python standard
       library.
 
-   `Original Python :mod:`logging` package <http://www.red-dove.com/python_logging.html>`_
+   `Original Python logging package <http://www.red-dove.com/python_logging.html>`_
       This is the original source for the :mod:`logging` package.  The version of the
       package available from this site is suitable for use with Python 1.5.2, 2.1.x
       and 2.2.x, which do not include the :mod:`logging` package in the standard
       library.
 
 
 Logger Objects
 --------------
 
 Loggers have the following attributes and methods. Note that Loggers are never
 instantiated directly, but always through the module-level function
-:func:`logging.getLogger(name)`.
+``logging.getLogger(name)``.
 
 
-.. data:: propagate
+.. attribute:: Logger.propagate
 
    If this evaluates to false, logging messages are not passed by this logger or by
    child loggers to higher level (ancestor) loggers. The constructor sets this
    attribute to 1.
 
 
-.. method:: XXX Class.setLevel(lvl)
+.. method:: Logger.setLevel(lvl)
 
    Sets the threshold for this logger to *lvl*. Logging messages which are less
    severe than *lvl* will be ignored. When a logger is created, the level is set to
    :const:`NOTSET` (which causes all messages to be processed when the logger is
    the root logger, or delegation to the parent when the logger is a non-root
    logger). Note that the root logger is created with level :const:`WARNING`.
 
    The term "delegation to the parent" means that if a logger has a level of
    NOTSET, its chain of ancestor loggers is traversed until either an ancestor with
    a level other than NOTSET is found, or the root is reached.
 
    If an ancestor is found with a level other than NOTSET, then that ancestor's
    level is treated as the effective level of the logger where the ancestor search
    began, and is used to determine how a logging event is handled.
 
    If the root is reached, and it has a level of NOTSET, then all messages will be
    processed. Otherwise, the root's level will be used as the effective level.
 
 
-.. method:: XXX Class.isEnabledFor(lvl)
+.. method:: Logger.isEnabledFor(lvl)
 
    Indicates if a message of severity *lvl* would be processed by this logger.
    This method checks first the module-level level set by
-   :func:`logging.disable(lvl)` and then the logger's effective level as determined
+   ``logging.disable(lvl)`` and then the logger's effective level as determined
    by :meth:`getEffectiveLevel`.
 
 
-.. method:: XXX Class.getEffectiveLevel()
+.. method:: Logger.getEffectiveLevel()
 
    Indicates the effective level for this logger. If a value other than
    :const:`NOTSET` has been set using :meth:`setLevel`, it is returned. Otherwise,
    the hierarchy is traversed towards the root until a value other than
    :const:`NOTSET` is found, and that value is returned.
 
 
-.. method:: XXX Class.debug(msg[, *args[, **kwargs]])
+.. method:: Logger.debug(msg[, *args[, **kwargs]])
 
    Logs a message with level :const:`DEBUG` on this logger. The *msg* is the
    message format string, and the *args* are the arguments which are merged into
    *msg* using the string formatting operator. (Note that this means that you can
    use keywords in the format string, together with a single dictionary argument.)
 
    There are two keyword arguments in *kwargs* which are inspected: *exc_info*
    which, if it does not evaluate as false, causes exception information to be
    added to the logging message. If an exception tuple (in the format returned by
    :func:`sys.exc_info`) is provided, it is used; otherwise, :func:`sys.exc_info`
    is called to get the exception information.
 
    The other optional keyword argument is *extra* which can be used to pass a
    dictionary which is used to populate the __dict__ of the LogRecord created for
    the logging event with user-defined attributes. These custom attributes can then
    be used as you like. For example, they could be incorporated into logged
    messages. For example::
 
       FORMAT = "%(asctime)-15s %(clientip)s %(user)-8s %(message)s"
       logging.basicConfig(format=FORMAT)
-      dict = { 'clientip' : '192.168.0.1', 'user' : 'fbloggs' }
+      d = { 'clientip' : '192.168.0.1', 'user' : 'fbloggs' }
       logger = logging.getLogger("tcpserver")
       logger.warning("Protocol problem: %s", "connection reset", extra=d)
 
    would print something like  ::
 
       2006-02-08 22:20:02,165 192.168.0.1 fbloggs  Protocol problem: connection reset
 
    The keys in the dictionary passed in *extra* should not clash with the keys used
    by the logging system. (See the :class:`Formatter` documentation for more
    information on which keys are used by the logging system.)
 
    If you choose to use these attributes in logged messages, you need to exercise
@@ -459,102 +900,106 @@
 
    While this might be annoying, this feature is intended for use in specialized
    circumstances, such as multi-threaded servers where the same code executes in
    many contexts, and interesting conditions which arise are dependent on this
    context (such as remote client IP address and authenticated user name, in the
    above example). In such circumstances, it is likely that specialized
    :class:`Formatter`\ s would be used with particular :class:`Handler`\ s.
 
    .. versionchanged:: 2.5
       *extra* was added.
 
 
-.. method:: XXX Class.info(msg[, *args[, **kwargs]])
+.. method:: Logger.info(msg[, *args[, **kwargs]])
 
    Logs a message with level :const:`INFO` on this logger. The arguments are
    interpreted as for :meth:`debug`.
 
 
-.. method:: XXX Class.warning(msg[, *args[, **kwargs]])
+.. method:: Logger.warning(msg[, *args[, **kwargs]])
 
    Logs a message with level :const:`WARNING` on this logger. The arguments are
    interpreted as for :meth:`debug`.
 
 
-.. method:: XXX Class.error(msg[, *args[, **kwargs]])
+.. method:: Logger.error(msg[, *args[, **kwargs]])
 
    Logs a message with level :const:`ERROR` on this logger. The arguments are
    interpreted as for :meth:`debug`.
 
 
-.. method:: XXX Class.critical(msg[, *args[, **kwargs]])
+.. method:: Logger.critical(msg[, *args[, **kwargs]])
 
    Logs a message with level :const:`CRITICAL` on this logger. The arguments are
    interpreted as for :meth:`debug`.
 
 
-.. method:: XXX Class.log(lvl, msg[, *args[, **kwargs]])
+.. method:: Logger.log(lvl, msg[, *args[, **kwargs]])
 
    Logs a message with integer level *lvl* on this logger. The other arguments are
    interpreted as for :meth:`debug`.
 
 
-.. method:: XXX Class.exception(msg[, *args])
+.. method:: Logger.exception(msg[, *args])
 
    Logs a message with level :const:`ERROR` on this logger. The arguments are
    interpreted as for :meth:`debug`. Exception info is added to the logging
    message. This method should only be called from an exception handler.
 
 
-.. method:: XXX Class.addFilter(filt)
+.. method:: Logger.addFilter(filt)
 
    Adds the specified filter *filt* to this logger.
 
 
-.. method:: XXX Class.removeFilter(filt)
+.. method:: Logger.removeFilter(filt)
 
    Removes the specified filter *filt* from this logger.
 
 
-.. method:: XXX Class.filter(record)
+.. method:: Logger.filter(record)
 
    Applies this logger's filters to the record and returns a true value if the
    record is to be processed.
 
 
-.. method:: XXX Class.addHandler(hdlr)
+.. method:: Logger.addHandler(hdlr)
 
    Adds the specified handler *hdlr* to this logger.
 
 
-.. method:: XXX Class.removeHandler(hdlr)
+.. method:: Logger.removeHandler(hdlr)
 
    Removes the specified handler *hdlr* from this logger.
 
 
-.. method:: XXX Class.findCaller()
+.. method:: Logger.findCaller()
 
-   Finds the caller's source filename and line number. Returns the filename and
-   line number as a 2-element tuple.
+   Finds the caller's source filename and line number. Returns the filename, line
+   number and function name as a 3-element tuple.
 
+   .. versionchanged:: 2.4
+      The function name was added. In earlier versions, the filename and line number
+      were returned as a 2-element tuple..
 
-.. method:: XXX Class.handle(record)
+
+.. method:: Logger.handle(record)
 
    Handles a record by passing it to all handlers associated with this logger and
    its ancestors (until a false value of *propagate* is found). This method is used
    for unpickled records received from a socket, as well as those created locally.
    Logger-level filtering is applied using :meth:`filter`.
 
 
-.. method:: XXX Class.makeRecord(name, lvl, fn, lno, msg, args, exc_info, func, extra)
+.. method:: Logger.makeRecord(name, lvl, fn, lno, msg, args, exc_info [, func, extra])
 
    This is a factory method which can be overridden in subclasses to create
    specialized :class:`LogRecord` instances.
 
    .. versionchanged:: 2.5
       *func* and *extra* were added.
 
 
 .. _minimal-example:
 
 Basic example
 -------------
@@ -599,25 +1044,25 @@
 which results in output (written to ``/tmp/myapp.log``) which should look
 something like the following::
 
    2004-07-02 13:00:08,743 DEBUG A debug message
    2004-07-02 13:00:08,743 INFO Some information
    2004-07-02 13:00:08,743 WARNING A shot across the bows
 
 This time, all messages with a severity of DEBUG or above were handled, and the
 format of the messages was also changed, and output went to the specified file
 rather than the console.
 
 Formatting uses standard Python string formatting - see section
-:ref:`typesseq-strings`. The format string takes the following common
+:ref:`string-formatting`. The format string takes the following common
 specifiers. For a complete list of specifiers, consult the :class:`Formatter`
 documentation.
 
 +-------------------+-----------------------------------------------+
 | Format            | Description                                   |
 +===================+===============================================+
 | ``%(name)s``      | Name of the logger (logging channel).         |
 +-------------------+-----------------------------------------------+
 | ``%(levelname)s`` | Text logging level for the message            |
 |                   | (``'DEBUG'``, ``'INFO'``, ``'WARNING'``,      |
 |                   | ``'ERROR'``, ``'CRITICAL'``).                 |
 +-------------------+-----------------------------------------------+
@@ -733,24 +1178,150 @@
    10-22 22:19 myapp.area1  DEBUG    Quick zephyrs blow, vexing daft Jim.
    10-22 22:19 myapp.area1  INFO     How quickly daft jumping zebras vex.
    10-22 22:19 myapp.area2  WARNING  Jail zesty vixen who grabbed pay from quack.
    10-22 22:19 myapp.area2  ERROR    The five boxing wizards jump quickly.
 
 As you can see, the DEBUG message only shows up in the file. The other messages
 are sent to both destinations.
 
 This example uses console and file handlers, but you can use any number and
 combination of handlers you choose.
 
 
+.. _context-info:
+
+Adding contextual information to your logging output
+----------------------------------------------------
+
+Sometimes you want logging output to contain contextual information in
+addition to the parameters passed to the logging call. For example, in a
+networked application, it may be desirable to log client-specific information
+in the log (e.g. remote client's username, or IP address). Although you could
+use the *extra* parameter to achieve this, it's not always convenient to pass
+the information in this way. While it might be tempting to create
+:class:`Logger` instances on a per-connection basis, this is not a good idea
+because these instances are not garbage collected. While this is not a problem
+in practice, when the number of :class:`Logger` instances is dependent on the
+level of granularity you want to use in logging an application, it could
+be hard to manage if the number of :class:`Logger` instances becomes
+effectively unbounded.
+
+An easy way in which you can pass contextual information to be output along
+with logging event information is to use the :class:`LoggerAdapter` class.
+This class is designed to look like a :class:`Logger`, so that you can call
+:meth:`debug`, :meth:`info`, :meth:`warning`, :meth:`error`,
+:meth:`exception`, :meth:`critical` and :meth:`log`. These methods have the
+same signatures as their counterparts in :class:`Logger`, so you can use the
+two types of instances interchangeably.
+
+When you create an instance of :class:`LoggerAdapter`, you pass it a
+:class:`Logger` instance and a dict-like object which contains your contextual
+information. When you call one of the logging methods on an instance of
+:class:`LoggerAdapter`, it delegates the call to the underlying instance of
+:class:`Logger` passed to its constructor, and arranges to pass the contextual
+information in the delegated call. Here's a snippet from the code of
+:class:`LoggerAdapter`::
+
+    def debug(self, msg, *args, **kwargs):
+        """
+        Delegate a debug call to the underlying logger, after adding
+        contextual information from this adapter instance.
+        """
+        msg, kwargs = self.process(msg, kwargs)
+        self.logger.debug(msg, *args, **kwargs)
+
+The :meth:`process` method of :class:`LoggerAdapter` is where the contextual
+information is added to the logging output. It's passed the message and
+keyword arguments of the logging call, and it passes back (potentially)
+modified versions of these to use in the call to the underlying logger. The
+default implementation of this method leaves the message alone, but inserts
+an "extra" key in the keyword argument whose value is the dict-like object
+passed to the constructor. Of course, if you had passed an "extra" keyword
+argument in the call to the adapter, it will be silently overwritten.
+
+The advantage of using "extra" is that the values in the dict-like object are
+merged into the :class:`LogRecord` instance's __dict__, allowing you to use
+customized strings with your :class:`Formatter` instances which know about
+the keys of the dict-like object. If you need a different method, e.g. if you
+want to prepend or append the contextual information to the message string,
+you just need to subclass :class:`LoggerAdapter` and override :meth:`process`
+to do what you need. Here's an example script which uses this class, which
+also illustrates what dict-like behaviour is needed from an arbitrary
+"dict-like" object for use in the constructor::
+
+   import logging
+
+   class ConnInfo:
+       """
+       An example class which shows how an arbitrary class can be used as
+       the 'extra' context information repository passed to a LoggerAdapter.
+       """
+
+       def __getitem__(self, name):
+           """
+           To allow this instance to look like a dict.
+           """
+           from random import choice
+           if name == "ip":
+               result = choice(["127.0.0.1", "192.168.0.1"])
+           elif name == "user":
+               result = choice(["jim", "fred", "sheila"])
+           else:
+               result = self.__dict__.get(name, "?")
+           return result
+
+       def __iter__(self):
+           """
+           To allow iteration over keys, which will be merged into
+           the LogRecord dict before formatting and output.
+           """
+           keys = ["ip", "user"]
+           keys.extend(self.__dict__.keys())
+           return keys.__iter__()
+
+   if __name__ == "__main__":
+       from random import choice
+       levels = (logging.DEBUG, logging.INFO, logging.WARNING, logging.ERROR, logging.CRITICAL)
+       a1 = logging.LoggerAdapter(logging.getLogger("a.b.c"),
+                                  { "ip" : "123.231.231.123", "user" : "sheila" })
+       logging.basicConfig(level=logging.DEBUG,
+                           format="%(asctime)-15s %(name)-5s %(levelname)-8s IP: %(ip)-15s User: %(user)-8s %(message)s")
+       a1.debug("A debug message")
+       a1.info("An info message with %s", "some parameters")
+       a2 = logging.LoggerAdapter(logging.getLogger("d.e.f"), ConnInfo())
+       for x in range(10):
+           lvl = choice(levels)
+           lvlname = logging.getLevelName(lvl)
+           a2.log(lvl, "A message at %s level with %d %s", lvlname, 2, "parameters")
+
+When this script is run, the output should look something like this::
+
+   2008-01-18 14:49:54,023 a.b.c DEBUG    IP: 123.231.231.123 User: sheila   A debug message
+   2008-01-18 14:49:54,023 a.b.c INFO     IP: 123.231.231.123 User: sheila   An info message with some parameters
+   2008-01-18 14:49:54,023 d.e.f CRITICAL IP: 192.168.0.1     User: jim      A message at CRITICAL level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f INFO     IP: 192.168.0.1     User: jim      A message at INFO level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f WARNING  IP: 192.168.0.1     User: sheila   A message at WARNING level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f ERROR    IP: 127.0.0.1       User: fred     A message at ERROR level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f ERROR    IP: 127.0.0.1       User: sheila   A message at ERROR level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f WARNING  IP: 192.168.0.1     User: sheila   A message at WARNING level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f WARNING  IP: 192.168.0.1     User: jim      A message at WARNING level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f INFO     IP: 192.168.0.1     User: fred     A message at INFO level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f WARNING  IP: 192.168.0.1     User: sheila   A message at WARNING level with 2 parameters
+   2008-01-18 14:49:54,033 d.e.f WARNING  IP: 127.0.0.1       User: jim      A message at WARNING level with 2 parameters
+
+.. versionadded:: 2.6
+
+The :class:`LoggerAdapter` class was not present in previous versions.
+
+
 .. _network-logging:
 
 Sending and receiving logging events across a network
 -----------------------------------------------------
 
 Let's say you want to send logging events across a network, and handle them at
 the receiving end. A simple way of doing this is attaching a
 :class:`SocketHandler` instance to the root logger at the sending end::
 
    import logging, logging.handlers
 
    rootLogger = logging.getLogger('')
@@ -873,382 +1444,440 @@
       69 myapp.area2     ERROR    The five boxing wizards jump quickly.
 
 
 Handler Objects
 ---------------
 
 Handlers have the following attributes and methods. Note that :class:`Handler`
 is never instantiated directly; this class acts as a base for more useful
 subclasses. However, the :meth:`__init__` method in subclasses needs to call
 :meth:`Handler.__init__`.
 
 
-.. method:: XXX Class.__init__(level=NOTSET)
+.. method:: Handler.__init__(level=NOTSET)
 
    Initializes the :class:`Handler` instance by setting its level, setting the list
    of filters to the empty list and creating a lock (using :meth:`createLock`) for
    serializing access to an I/O mechanism.
 
 
-.. method:: XXX Class.createLock()
+.. method:: Handler.createLock()
 
    Initializes a thread lock which can be used to serialize access to underlying
    I/O functionality which may not be threadsafe.
 
 
-.. method:: XXX Class.acquire()
+.. method:: Handler.acquire()
 
    Acquires the thread lock created with :meth:`createLock`.
 
 
-.. method:: XXX Class.release()
+.. method:: Handler.release()
 
    Releases the thread lock acquired with :meth:`acquire`.
 
 
-.. method:: XXX Class.setLevel(lvl)
+.. method:: Handler.setLevel(lvl)
 
    Sets the threshold for this handler to *lvl*. Logging messages which are less
    severe than *lvl* will be ignored. When a handler is created, the level is set
    to :const:`NOTSET` (which causes all messages to be processed).
 
 
-.. method:: XXX Class.setFormatter(form)
+.. method:: Handler.setFormatter(form)
 
    Sets the :class:`Formatter` for this handler to *form*.
 
 
-.. method:: XXX Class.addFilter(filt)
+.. method:: Handler.addFilter(filt)
 
    Adds the specified filter *filt* to this handler.
 
 
-.. method:: XXX Class.removeFilter(filt)
+.. method:: Handler.removeFilter(filt)
 
    Removes the specified filter *filt* from this handler.
 
 
-.. method:: XXX Class.filter(record)
+.. method:: Handler.filter(record)
 
    Applies this handler's filters to the record and returns a true value if the
    record is to be processed.
 
 
-.. method:: XXX Class.flush()
+.. method:: Handler.flush()
 
    Ensure all logging output has been flushed. This version does nothing and is
    intended to be implemented by subclasses.
 
 
-.. method:: XXX Class.close()
+.. method:: Handler.close()
 
-   Tidy up any resources used by the handler. This version does nothing and is
-   intended to be implemented by subclasses.
+   Tidy up any resources used by the handler. This version does no output but
+   removes the handler from an internal list of handlers which is closed when
+   :func:`shutdown` is called. Subclasses should ensure that this gets called
+   from overridden :meth:`close` methods.
 
 
-.. method:: XXX Class.handle(record)
+.. method:: Handler.handle(record)
 
    Conditionally emits the specified logging record, depending on filters which may
    have been added to the handler. Wraps the actual emission of the record with
    acquisition/release of the I/O thread lock.
 
 
-.. method:: XXX Class.handleError(record)
+.. method:: Handler.handleError(record)
 
    This method should be called from handlers when an exception is encountered
    during an :meth:`emit` call. By default it does nothing, which means that
    exceptions get silently ignored. This is what is mostly wanted for a logging
    system - most users will not care about errors in the logging system, they are
    more interested in application errors. You could, however, replace this with a
    custom handler if you wish. The specified record is the one which was being
    processed when the exception occurred.
 
 
-.. method:: XXX Class.format(record)
+.. method:: Handler.format(record)
 
    Do formatting for a record - if a formatter is set, use it. Otherwise, use the
    default formatter for the module.
 
 
-.. method:: XXX Class.emit(record)
+.. method:: Handler.emit(record)
 
    Do whatever it takes to actually log the specified logging record. This version
    is intended to be implemented by subclasses and so raises a
    :exc:`NotImplementedError`.
 
 
 StreamHandler
 ^^^^^^^^^^^^^
 
+.. module:: logging.handlers
+
 The :class:`StreamHandler` class, located in the core :mod:`logging` package,
-sends logging output to streams such as *sys.stdout*, *sys.stderr* or any file-
-like object (or, more precisely, any object which supports :meth:`write` and
-:meth:`flush` methods).
+sends logging output to streams such as *sys.stdout*, *sys.stderr* or any
+file-like object (or, more precisely, any object which supports :meth:`write`
+and :meth:`flush` methods).
 
 
 .. class:: StreamHandler([strm])
 
    Returns a new instance of the :class:`StreamHandler` class. If *strm* is
    specified, the instance will use it for logging output; otherwise, *sys.stderr*
    will be used.
 
 
-.. method:: StreamHandler.emit(record)
+   .. method:: emit(record)
 
-   If a formatter is specified, it is used to format the record. The record is then
-   written to the stream with a trailing newline. If exception information is
-   present, it is formatted using :func:`traceback.print_exception` and appended to
-   the stream.
+      If a formatter is specified, it is used to format the record. The record
+      is then written to the stream with a trailing newline. If exception
+      information is present, it is formatted using
+      :func:`traceback.print_exception` and appended to the stream.
 
 
-.. method:: StreamHandler.flush()
+   .. method:: flush()
 
-   Flushes the stream by calling its :meth:`flush` method. Note that the
-   :meth:`close` method is inherited from :class:`Handler` and so does nothing, so
-   an explicit :meth:`flush` call may be needed at times.
+      Flushes the stream by calling its :meth:`flush` method. Note that the
+      :meth:`close` method is inherited from :class:`Handler` and so does
+      no output, so an explicit :meth:`flush` call may be needed at times.
 
 
 FileHandler
 ^^^^^^^^^^^
 
 The :class:`FileHandler` class, located in the core :mod:`logging` package,
 sends logging output to a disk file.  It inherits the output functionality from
 :class:`StreamHandler`.
 
 
-.. class:: FileHandler(filename[, mode])
+.. class:: FileHandler(filename[, mode[, encoding[, delay]]])
 
    Returns a new instance of the :class:`FileHandler` class. The specified file is
    opened and used as the stream for logging. If *mode* is not specified,
-   :const:`'a'` is used. By default, the file grows indefinitely.
+   :const:`'a'` is used.  If *encoding* is not *None*, it is used to open the file
+   with that encoding.  If *delay* is true, then file opening is deferred until the
+   first call to :meth:`emit`. By default, the file grows indefinitely.
+
+
+   .. method:: close()
 
+      Closes the file.
 
-.. method:: FileHandler.close()
 
-   Closes the file.
+   .. method:: emit(record)
 
+      Outputs the record to the file.
 
-.. method:: FileHandler.emit(record)
 
-   Outputs the record to the file.
+See :ref:`library-config` for more information on how to use
+:class:`NullHandler`.
+
+WatchedFileHandler
+^^^^^^^^^^^^^^^^^^
+
+.. versionadded:: 2.6
+
+The :class:`WatchedFileHandler` class, located in the :mod:`logging.handlers`
+module, is a :class:`FileHandler` which watches the file it is logging to. If
+the file changes, it is closed and reopened using the file name.
+
+A file change can happen because of usage of programs such as *newsyslog* and
+*logrotate* which perform log file rotation. This handler, intended for use
+under Unix/Linux, watches the file to see if it has changed since the last emit.
+(A file is deemed to have changed if its device or inode have changed.) If the
+file has changed, the old file stream is closed, and the file opened to get a
+new stream.
+
+This handler is not appropriate for use under Windows, because under Windows
+open log files cannot be moved or renamed - logging opens the files with
+exclusive locks - and so there is no need for such a handler. Furthermore,
+*ST_INO* is not supported under Windows; :func:`stat` always returns zero for
+this value.
+
+
+.. class:: WatchedFileHandler(filename[,mode[, encoding[, delay]]])
+
+   Returns a new instance of the :class:`WatchedFileHandler` class. The specified
+   file is opened and used as the stream for logging. If *mode* is not specified,
+   :const:`'a'` is used.  If *encoding* is not *None*, it is used to open the file
+   with that encoding.  If *delay* is true, then file opening is deferred until the
+   first call to :meth:`emit`.  By default, the file grows indefinitely.
+
+
+   .. method:: emit(record)
+
+      Outputs the record to the file, but first checks to see if the file has
+      changed.  If it has, the existing stream is flushed and closed and the
+      file opened again, before outputting the record to the file.
 
 
 RotatingFileHandler
 ^^^^^^^^^^^^^^^^^^^
 
 The :class:`RotatingFileHandler` class, located in the :mod:`logging.handlers`
 module, supports rotation of disk log files.
 
 
-.. class:: RotatingFileHandler(filename[, mode[, maxBytes[, backupCount]]])
+.. class:: RotatingFileHandler(filename[, mode[, maxBytes[, backupCount[, encoding[, delay]]]]])
 
    Returns a new instance of the :class:`RotatingFileHandler` class. The specified
    file is opened and used as the stream for logging. If *mode* is not specified,
-   ``'a'`` is used. By default, the file grows indefinitely.
+   ``'a'`` is used.  If *encoding* is not *None*, it is used to open the file
+   with that encoding.  If *delay* is true, then file opening is deferred until the
+   first call to :meth:`emit`.  By default, the file grows indefinitely.
 
    You can use the *maxBytes* and *backupCount* values to allow the file to
    :dfn:`rollover` at a predetermined size. When the size is about to be exceeded,
    the file is closed and a new file is silently opened for output. Rollover occurs
    whenever the current log file is nearly *maxBytes* in length; if *maxBytes* is
    zero, rollover never occurs.  If *backupCount* is non-zero, the system will save
    old log files by appending the extensions ".1", ".2" etc., to the filename. For
    example, with a *backupCount* of 5 and a base file name of :file:`app.log`, you
    would get :file:`app.log`, :file:`app.log.1`, :file:`app.log.2`, up to
    :file:`app.log.5`. The file being written to is always :file:`app.log`.  When
    this file is filled, it is closed and renamed to :file:`app.log.1`, and if files
    :file:`app.log.1`, :file:`app.log.2`, etc.  exist, then they are renamed to
    :file:`app.log.2`, :file:`app.log.3` etc.  respectively.
 
 
-.. method:: RotatingFileHandler.doRollover()
+   .. method:: doRollover()
 
-   Does a rollover, as described above.
+      Does a rollover, as described above.
 
 
-.. method:: RotatingFileHandler.emit(record)
+   .. method:: emit(record)
 
-   Outputs the record to the file, catering for rollover as described previously.
+      Outputs the record to the file, catering for rollover as described
+      previously.
 
 
 TimedRotatingFileHandler
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
 The :class:`TimedRotatingFileHandler` class, located in the
 :mod:`logging.handlers` module, supports rotation of disk log files at certain
 timed intervals.
 
 
-.. class:: TimedRotatingFileHandler(filename [,when [,interval [,backupCount]]])
+.. class:: TimedRotatingFileHandler(filename [,when [,interval [,backupCount[, encoding[, delay[, utc]]]]]])
 
    Returns a new instance of the :class:`TimedRotatingFileHandler` class. The
    specified file is opened and used as the stream for logging. On rotating it also
    sets the filename suffix. Rotating happens based on the product of *when* and
    *interval*.
 
    You can use the *when* to specify the type of *interval*. The list of possible
-   values is, note that they are not case sensitive:
+   values is below.  Note that they are not case sensitive.
 
-   +----------+-----------------------+
-   | Value    | Type of interval      |
-   +==========+=======================+
-   | S        | Seconds               |
-   +----------+-----------------------+
-   | M        | Minutes               |
-   +----------+-----------------------+
-   | H        | Hours                 |
-   +----------+-----------------------+
-   | D        | Days                  |
-   +----------+-----------------------+
-   | W        | Week day (0=Monday)   |
-   +----------+-----------------------+
-   | midnight | Roll over at midnight |
-   +----------+-----------------------+
-
-   If *backupCount* is non-zero, the system will save old log files by appending
-   extensions to the filename. The extensions are date-and-time based, using the
-   strftime format ``%Y-%m-%d_%H-%M-%S`` or a leading portion thereof, depending on
-   the rollover interval. At most *backupCount* files will be kept, and if more
-   would be created when rollover occurs, the oldest one is deleted.
+   +----------------+-----------------------+
+   | Value          | Type of interval      |
+   +================+=======================+
+   | ``'S'``        | Seconds               |
+   +----------------+-----------------------+
+   | ``'M'``        | Minutes               |
+   +----------------+-----------------------+
+   | ``'H'``        | Hours                 |
+   +----------------+-----------------------+
+   | ``'D'``        | Days                  |
+   +----------------+-----------------------+
+   | ``'W'``        | Week day (0=Monday)   |
+   +----------------+-----------------------+
+   | ``'midnight'`` | Roll over at midnight |
+   +----------------+-----------------------+
+
+   The system will save old log files by appending extensions to the filename.
+   The extensions are date-and-time based, using the strftime format
+   ``%Y-%m-%d_%H-%M-%S`` or a leading portion thereof, depending on the
+   rollover interval.
+   If the *utc* argument is true, times in UTC will be used; otherwise
+   local time is used.
+
+   If *backupCount* is nonzero, at most *backupCount* files
+   will be kept, and if more would be created when rollover occurs, the oldest
+   one is deleted. The deletion logic uses the interval to determine which
+   files to delete, so changing the interval may leave old files lying around.
 
 
-.. method:: TimedRotatingFileHandler.doRollover()
+   .. method:: doRollover()
 
-   Does a rollover, as described above.
+      Does a rollover, as described above.
 
 
-.. method:: TimedRotatingFileHandler.emit(record)
+   .. method:: emit(record)
 
-   Outputs the record to the file, catering for rollover as described above.
+      Outputs the record to the file, catering for rollover as described above.
 
 
 SocketHandler
 ^^^^^^^^^^^^^
 
 The :class:`SocketHandler` class, located in the :mod:`logging.handlers` module,
 sends logging output to a network socket. The base class uses a TCP socket.
 
 
 .. class:: SocketHandler(host, port)
 
    Returns a new instance of the :class:`SocketHandler` class intended to
    communicate with a remote machine whose address is given by *host* and *port*.
 
 
-.. method:: SocketHandler.close()
-
-   Closes the socket.
-
+   .. method:: close()
 
-.. method:: SocketHandler.handleError()
+      Closes the socket.
 
 
-.. method:: SocketHandler.emit()
+   .. method:: emit()
 
-   Pickles the record's attribute dictionary and writes it to the socket in binary
-   format. If there is an error with the socket, silently drops the packet. If the
-   connection was previously lost, re-establishes the connection. To unpickle the
-   record at the receiving end into a :class:`LogRecord`, use the
-   :func:`makeLogRecord` function.
+      Pickles the record's attribute dictionary and writes it to the socket in
+      binary format. If there is an error with the socket, silently drops the
+      packet. If the connection was previously lost, re-establishes the
+      connection. To unpickle the record at the receiving end into a
+      :class:`LogRecord`, use the :func:`makeLogRecord` function.
 
 
-.. method:: SocketHandler.handleError()
+   .. method:: handleError()
 
-   Handles an error which has occurred during :meth:`emit`. The most likely cause
-   is a lost connection. Closes the socket so that we can retry on the next event.
+      Handles an error which has occurred during :meth:`emit`. The most likely
+      cause is a lost connection. Closes the socket so that we can retry on the
+      next event.
 
 
-.. method:: SocketHandler.makeSocket()
+   .. method:: makeSocket()
 
-   This is a factory method which allows subclasses to define the precise type of
-   socket they want. The default implementation creates a TCP socket
-   (:const:`socket.SOCK_STREAM`).
+      This is a factory method which allows subclasses to define the precise
+      type of socket they want. The default implementation creates a TCP socket
+      (:const:`socket.SOCK_STREAM`).
 
 
-.. method:: SocketHandler.makePickle(record)
+   .. method:: makePickle(record)
 
-   Pickles the record's attribute dictionary in binary format with a length prefix,
-   and returns it ready for transmission across the socket.
+      Pickles the record's attribute dictionary in binary format with a length
+      prefix, and returns it ready for transmission across the socket.
 
 
-.. method:: SocketHandler.send(packet)
+   .. method:: send(packet)
 
-   Send a pickled string *packet* to the socket. This function allows for partial
-   sends which can happen when the network is busy.
+      Send a pickled string *packet* to the socket. This function allows for
+      partial sends which can happen when the network is busy.
 
 
 DatagramHandler
 ^^^^^^^^^^^^^^^
 
 The :class:`DatagramHandler` class, located in the :mod:`logging.handlers`
 module, inherits from :class:`SocketHandler` to support sending logging messages
 over UDP sockets.
 
 
 .. class:: DatagramHandler(host, port)
 
    Returns a new instance of the :class:`DatagramHandler` class intended to
    communicate with a remote machine whose address is given by *host* and *port*.
 
 
-.. method:: DatagramHandler.emit()
+   .. method:: emit()
 
-   Pickles the record's attribute dictionary and writes it to the socket in binary
-   format. If there is an error with the socket, silently drops the packet. To
-   unpickle the record at the receiving end into a :class:`LogRecord`, use the
-   :func:`makeLogRecord` function.
+      Pickles the record's attribute dictionary and writes it to the socket in
+      binary format. If there is an error with the socket, silently drops the
+      packet. To unpickle the record at the receiving end into a
+      :class:`LogRecord`, use the :func:`makeLogRecord` function.
 
 
-.. method:: DatagramHandler.makeSocket()
+   .. method:: makeSocket()
 
-   The factory method of :class:`SocketHandler` is here overridden to create a UDP
-   socket (:const:`socket.SOCK_DGRAM`).
+      The factory method of :class:`SocketHandler` is here overridden to create
+      a UDP socket (:const:`socket.SOCK_DGRAM`).
 
 
-.. method:: DatagramHandler.send(s)
+   .. method:: send(s)
 
-   Send a pickled string to a socket.
+      Send a pickled string to a socket.
 
 
 SysLogHandler
 ^^^^^^^^^^^^^
 
 The :class:`SysLogHandler` class, located in the :mod:`logging.handlers` module,
 supports sending logging messages to a remote or local Unix syslog.
 
 
 .. class:: SysLogHandler([address[, facility]])
 
    Returns a new instance of the :class:`SysLogHandler` class intended to
    communicate with a remote Unix machine whose address is given by *address* in
    the form of a ``(host, port)`` tuple.  If *address* is not specified,
-   ``('localhost', 514)`` is used.  The address is used to open a UDP socket.  If
-   *facility* is not specified, :const:`LOG_USER` is used.
+   ``('localhost', 514)`` is used.  The address is used to open a UDP socket.  An
+   alternative to providing a ``(host, port)`` tuple is providing an address as a
+   string, for example "/dev/log". In this case, a Unix domain socket is used to
+   send the message to the syslog. If *facility* is not specified,
+   :const:`LOG_USER` is used.
 
 
-.. method:: SysLogHandler.close()
+   .. method:: close()
 
-   Closes the socket to the remote host.
+      Closes the socket to the remote host.
 
 
-.. method:: SysLogHandler.emit(record)
+   .. method:: emit(record)
 
-   The record is formatted, and then sent to the syslog server. If exception
-   information is present, it is *not* sent to the server.
+      The record is formatted, and then sent to the syslog server. If exception
+      information is present, it is *not* sent to the server.
 
 
-.. method:: SysLogHandler.encodePriority(facility, priority)
+   .. method:: encodePriority(facility, priority)
 
-   Encodes the facility and priority into an integer. You can pass in strings or
-   integers - if strings are passed, internal mapping dictionaries are used to
-   convert them to integers.
+      Encodes the facility and priority into an integer. You can pass in strings
+      or integers - if strings are passed, internal mapping dictionaries are
+      used to convert them to integers.
 
 
 NTEventLogHandler
 ^^^^^^^^^^^^^^^^^
 
 The :class:`NTEventLogHandler` class, located in the :mod:`logging.handlers`
 module, supports sending logging messages to a local Windows NT, Windows 2000 or
 Windows XP event log. Before you can use it, you need Mark Hammond's Win32
 extensions for Python installed.
 
 
 .. class:: NTEventLogHandler(appname[, dllname[, logtype]])
@@ -1258,360 +1887,419 @@
    appropriate registry entry is created using this name. The *dllname* should give
    the fully qualified pathname of a .dll or .exe which contains message
    definitions to hold in the log (if not specified, ``'win32service.pyd'`` is used
    - this is installed with the Win32 extensions and contains some basic
    placeholder message definitions. Note that use of these placeholders will make
    your event logs big, as the entire message source is held in the log. If you
    want slimmer logs, you have to pass in the name of your own .dll or .exe which
    contains the message definitions you want to use in the event log). The
    *logtype* is one of ``'Application'``, ``'System'`` or ``'Security'``, and
    defaults to ``'Application'``.
 
 
-.. method:: NTEventLogHandler.close()
+   .. method:: close()
 
-   At this point, you can remove the application name from the registry as a source
-   of event log entries. However, if you do this, you will not be able to see the
-   events as you intended in the Event Log Viewer - it needs to be able to access
-   the registry to get the .dll name. The current version does not do this (in fact
-   it doesn't do anything).
+      At this point, you can remove the application name from the registry as a
+      source of event log entries. However, if you do this, you will not be able
+      to see the events as you intended in the Event Log Viewer - it needs to be
+      able to access the registry to get the .dll name. The current version does
+      not do this.
 
 
-.. method:: NTEventLogHandler.emit(record)
+   .. method:: emit(record)
 
-   Determines the message ID, event category and event type, and then logs the
-   message in the NT event log.
+      Determines the message ID, event category and event type, and then logs
+      the message in the NT event log.
 
 
-.. method:: NTEventLogHandler.getEventCategory(record)
+   .. method:: getEventCategory(record)
 
-   Returns the event category for the record. Override this if you want to specify
-   your own categories. This version returns 0.
+      Returns the event category for the record. Override this if you want to
+      specify your own categories. This version returns 0.
 
 
-.. method:: NTEventLogHandler.getEventType(record)
+   .. method:: getEventType(record)
 
-   Returns the event type for the record. Override this if you want to specify your
-   own types. This version does a mapping using the handler's typemap attribute,
-   which is set up in :meth:`__init__` to a dictionary which contains mappings for
-   :const:`DEBUG`, :const:`INFO`, :const:`WARNING`, :const:`ERROR` and
-   :const:`CRITICAL`. If you are using your own levels, you will either need to
-   override this method or place a suitable dictionary in the handler's *typemap*
-   attribute.
+      Returns the event type for the record. Override this if you want to
+      specify your own types. This version does a mapping using the handler's
+      typemap attribute, which is set up in :meth:`__init__` to a dictionary
+      which contains mappings for :const:`DEBUG`, :const:`INFO`,
+      :const:`WARNING`, :const:`ERROR` and :const:`CRITICAL`. If you are using
+      your own levels, you will either need to override this method or place a
+      suitable dictionary in the handler's *typemap* attribute.
 
 
-.. method:: NTEventLogHandler.getMessageID(record)
+   .. method:: getMessageID(record)
 
-   Returns the message ID for the record. If you are using your own messages, you
-   could do this by having the *msg* passed to the logger being an ID rather than a
-   format string. Then, in here, you could use a dictionary lookup to get the
-   message ID. This version returns 1, which is the base message ID in
-   :file:`win32service.pyd`.
+      Returns the message ID for the record. If you are using your own messages,
+      you could do this by having the *msg* passed to the logger being an ID
+      rather than a format string. Then, in here, you could use a dictionary
+      lookup to get the message ID. This version returns 1, which is the base
+      message ID in :file:`win32service.pyd`.
 
 
 SMTPHandler
 ^^^^^^^^^^^
 
 The :class:`SMTPHandler` class, located in the :mod:`logging.handlers` module,
 supports sending logging messages to an email address via SMTP.
 
 
-.. class:: SMTPHandler(mailhost, fromaddr, toaddrs, subject)
+.. class:: SMTPHandler(mailhost, fromaddr, toaddrs, subject[, credentials])
 
    Returns a new instance of the :class:`SMTPHandler` class. The instance is
    initialized with the from and to addresses and subject line of the email. The
    *toaddrs* should be a list of strings. To specify a non-standard SMTP port, use
    the (host, port) tuple format for the *mailhost* argument. If you use a string,
-   the standard SMTP port is used.
+   the standard SMTP port is used. If your SMTP server requires authentication, you
+   can specify a (username, password) tuple for the *credentials* argument.
 
+   .. versionchanged:: 2.6
+      *credentials* was added.
 
-.. method:: SMTPHandler.emit(record)
 
-   Formats the record and sends it to the specified addressees.
+   .. method:: emit(record)
 
+      Formats the record and sends it to the specified addressees.
 
-.. method:: SMTPHandler.getSubject(record)
 
-   If you want to specify a subject line which is record-dependent, override this
-   method.
+   .. method:: getSubject(record)
+
+      If you want to specify a subject line which is record-dependent, override
+      this method.
 
 
 MemoryHandler
 ^^^^^^^^^^^^^
 
 The :class:`MemoryHandler` class, located in the :mod:`logging.handlers` module,
 supports buffering of logging records in memory, periodically flushing them to a
 :dfn:`target` handler. Flushing occurs whenever the buffer is full, or when an
 event of a certain severity or greater is seen.
 
 :class:`MemoryHandler` is a subclass of the more general
 :class:`BufferingHandler`, which is an abstract class. This buffers logging
 records in memory. Whenever each record is added to the buffer, a check is made
 by calling :meth:`shouldFlush` to see if the buffer should be flushed.  If it
 should, then :meth:`flush` is expected to do the needful.
 
 
 .. class:: BufferingHandler(capacity)
 
    Initializes the handler with a buffer of the specified capacity.
 
 
-.. method:: BufferingHandler.emit(record)
+   .. method:: emit(record)
 
-   Appends the record to the buffer. If :meth:`shouldFlush` returns true, calls
-   :meth:`flush` to process the buffer.
+      Appends the record to the buffer. If :meth:`shouldFlush` returns true,
+      calls :meth:`flush` to process the buffer.
 
 
-.. method:: BufferingHandler.flush()
+   .. method:: flush()
 
-   You can override this to implement custom flushing behavior. This version just
-   zaps the buffer to empty.
+      You can override this to implement custom flushing behavior. This version
+      just zaps the buffer to empty.
 
 
-.. method:: BufferingHandler.shouldFlush(record)
+   .. method:: shouldFlush(record)
 
-   Returns true if the buffer is up to capacity. This method can be overridden to
-   implement custom flushing strategies.
+      Returns true if the buffer is up to capacity. This method can be
+      overridden to implement custom flushing strategies.
 
 
 .. class:: MemoryHandler(capacity[, flushLevel [, target]])
 
    Returns a new instance of the :class:`MemoryHandler` class. The instance is
    initialized with a buffer size of *capacity*. If *flushLevel* is not specified,
    :const:`ERROR` is used. If no *target* is specified, the target will need to be
    set using :meth:`setTarget` before this handler does anything useful.
 
 
-.. method:: MemoryHandler.close()
+   .. method:: close()
 
-   Calls :meth:`flush`, sets the target to :const:`None` and clears the buffer.
+      Calls :meth:`flush`, sets the target to :const:`None` and clears the
+      buffer.
 
 
-.. method:: MemoryHandler.flush()
+   .. method:: flush()
 
-   For a :class:`MemoryHandler`, flushing means just sending the buffered records
-   to the target, if there is one. Override if you want different behavior.
+      For a :class:`MemoryHandler`, flushing means just sending the buffered
+      records to the target, if there is one. Override if you want different
+      behavior.
 
 
-.. method:: MemoryHandler.setTarget(target)
+   .. method:: setTarget(target)
 
-   Sets the target handler for this handler.
+      Sets the target handler for this handler.
 
 
-.. method:: MemoryHandler.shouldFlush(record)
+   .. method:: shouldFlush(record)
 
-   Checks for buffer full or a record at the *flushLevel* or higher.
+      Checks for buffer full or a record at the *flushLevel* or higher.
 
 
 HTTPHandler
 ^^^^^^^^^^^
 
 The :class:`HTTPHandler` class, located in the :mod:`logging.handlers` module,
 supports sending logging messages to a Web server, using either ``GET`` or
 ``POST`` semantics.
 
 
 .. class:: HTTPHandler(host, url[, method])
 
    Returns a new instance of the :class:`HTTPHandler` class. The instance is
    initialized with a host address, url and HTTP method. The *host* can be of the
    form ``host:port``, should you need to use a specific port number. If no
    *method* is specified, ``GET`` is used.
 
 
-.. method:: HTTPHandler.emit(record)
+   .. method:: emit(record)
+
+      Sends the record to the Web server as an URL-encoded dictionary.
 
-   Sends the record to the Web server as an URL-encoded dictionary.
 
+.. _formatter-objects:
 
 Formatter Objects
 -----------------
 
+.. currentmodule:: logging
+
 :class:`Formatter`\ s have the following attributes and methods. They are
 responsible for converting a :class:`LogRecord` to (usually) a string which can
 be interpreted by either a human or an external system. The base
 :class:`Formatter` allows a formatting string to be specified. If none is
 supplied, the default value of ``'%(message)s'`` is used.
 
 A Formatter can be initialized with a format string which makes use of knowledge
 of the :class:`LogRecord` attributes - such as the default value mentioned above
 making use of the fact that the user's message and arguments are pre-formatted
 into a :class:`LogRecord`'s *message* attribute.  This format string contains
-standard python %-style mapping keys. See section :ref:`typesseq-strings`,
-"String Formatting Operations," for more information on string formatting.
+standard python %-style mapping keys. See section :ref:`string-formatting`
+for more information on string formatting.
 
 Currently, the useful mapping keys in a :class:`LogRecord` are:
 
-+--------------------+-----------------------------------------------+
-| Format             | Description                                   |
-+====================+===============================================+
-| ``%(name)s``       | Name of the logger (logging channel).         |
-+--------------------+-----------------------------------------------+
-| ``%(levelno)s``    | Numeric logging level for the message         |
-|                    | (:const:`DEBUG`, :const:`INFO`,               |
-|                    | :const:`WARNING`, :const:`ERROR`,             |
-|                    | :const:`CRITICAL`).                           |
-+--------------------+-----------------------------------------------+
-| ``%(levelname)s``  | Text logging level for the message            |
-|                    | (``'DEBUG'``, ``'INFO'``, ``'WARNING'``,      |
-|                    | ``'ERROR'``, ``'CRITICAL'``).                 |
-+--------------------+-----------------------------------------------+
-| ``%(pathname)s``   | Full pathname of the source file where the    |
-|                    | logging call was issued (if available).       |
-+--------------------+-----------------------------------------------+
-| ``%(filename)s``   | Filename portion of pathname.                 |
-+--------------------+-----------------------------------------------+
-| ``%(module)s``     | Module (name portion of filename).            |
-+--------------------+-----------------------------------------------+
-| ``%(funcName)s``   | Name of function containing the logging call. |
-+--------------------+-----------------------------------------------+
-| ``%(lineno)d``     | Source line number where the logging call was |
-|                    | issued (if available).                        |
-+--------------------+-----------------------------------------------+
-| ``%(created)f``    | Time when the :class:`LogRecord` was created  |
-|                    | (as returned by :func:`time.time`).           |
-+--------------------+-----------------------------------------------+
-| ``%(asctime)s``    | Human-readable time when the                  |
-|                    | :class:`LogRecord` was created.  By default   |
-|                    | this is of the form "2003-07-08 16:49:45,896" |
-|                    | (the numbers after the comma are millisecond  |
-|                    | portion of the time).                         |
-+--------------------+-----------------------------------------------+
-| ``%(msecs)d``      | Millisecond portion of the time when the      |
-|                    | :class:`LogRecord` was created.               |
-+--------------------+-----------------------------------------------+
-| ``%(thread)d``     | Thread ID (if available).                     |
-+--------------------+-----------------------------------------------+
-| ``%(threadName)s`` | Thread name (if available).                   |
-+--------------------+-----------------------------------------------+
-| ``%(process)d``    | Process ID (if available).                    |
-+--------------------+-----------------------------------------------+
-| ``%(message)s``    | The logged message, computed as ``msg %       |
-|                    | args``.                                       |
-+--------------------+-----------------------------------------------+
++-------------------------+-----------------------------------------------+
+| Format                  | Description                                   |
++=========================+===============================================+
+| ``%(name)s``            | Name of the logger (logging channel).         |
++-------------------------+-----------------------------------------------+
+| ``%(levelno)s``         | Numeric logging level for the message         |
+|                         | (:const:`DEBUG`, :const:`INFO`,               |
+|                         | :const:`WARNING`, :const:`ERROR`,             |
+|                         | :const:`CRITICAL`).                           |
++-------------------------+-----------------------------------------------+
+| ``%(levelname)s``       | Text logging level for the message            |
+|                         | (``'DEBUG'``, ``'INFO'``, ``'WARNING'``,      |
+|                         | ``'ERROR'``, ``'CRITICAL'``).                 |
++-------------------------+-----------------------------------------------+
+| ``%(pathname)s``        | Full pathname of the source file where the    |
+|                         | logging call was issued (if available).       |
++-------------------------+-----------------------------------------------+
+| ``%(filename)s``        | Filename portion of pathname.                 |
++-------------------------+-----------------------------------------------+
+| ``%(module)s``          | Module (name portion of filename).            |
++-------------------------+-----------------------------------------------+
+| ``%(funcName)s``        | Name of function containing the logging call. |
++-------------------------+-----------------------------------------------+
+| ``%(lineno)d``          | Source line number where the logging call was |
+|                         | issued (if available).                        |
++-------------------------+-----------------------------------------------+
+| ``%(created)f``         | Time when the :class:`LogRecord` was created  |
+|                         | (as returned by :func:`time.time`).           |
++-------------------------+-----------------------------------------------+
+| ``%(relativeCreated)d`` | Time in milliseconds when the LogRecord was   |
+|                         | created, relative to the time the logging     |
+|                         | module was loaded.                            |
++-------------------------+-----------------------------------------------+
+| ``%(asctime)s``         | Human-readable time when the                  |
+|                         | :class:`LogRecord` was created.  By default   |
+|                         | this is of the form "2003-07-08 16:49:45,896" |
+|                         | (the numbers after the comma are millisecond  |
+|                         | portion of the time).                         |
++-------------------------+-----------------------------------------------+
+| ``%(msecs)d``           | Millisecond portion of the time when the      |
+|                         | :class:`LogRecord` was created.               |
++-------------------------+-----------------------------------------------+
+| ``%(thread)d``          | Thread ID (if available).                     |
++-------------------------+-----------------------------------------------+
+| ``%(threadName)s``      | Thread name (if available).                   |
++-------------------------+-----------------------------------------------+
+| ``%(process)d``         | Process ID (if available).                    |
++-------------------------+-----------------------------------------------+
+| ``%(message)s``         | The logged message, computed as ``msg %       |
+|                         | args``.                                       |
++-------------------------+-----------------------------------------------+
 
 .. versionchanged:: 2.5
    *funcName* was added.
 
 
 .. class:: Formatter([fmt[, datefmt]])
 
    Returns a new instance of the :class:`Formatter` class. The instance is
    initialized with a format string for the message as a whole, as well as a format
    string for the date/time portion of a message. If no *fmt* is specified,
    ``'%(message)s'`` is used. If no *datefmt* is specified, the ISO8601 date format
    is used.
 
 
-.. method:: Formatter.format(record)
-
-   The record's attribute dictionary is used as the operand to a string formatting
-   operation. Returns the resulting string. Before formatting the dictionary, a
-   couple of preparatory steps are carried out. The *message* attribute of the
-   record is computed using *msg* % *args*. If the formatting string contains
-   ``'(asctime)'``, :meth:`formatTime` is called to format the event time. If there
-   is exception information, it is formatted using :meth:`formatException` and
-   appended to the message.
-
-
-.. method:: Formatter.formatTime(record[, datefmt])
-
-   This method should be called from :meth:`format` by a formatter which wants to
-   make use of a formatted time. This method can be overridden in formatters to
-   provide for any specific requirement, but the basic behavior is as follows: if
-   *datefmt* (a string) is specified, it is used with :func:`time.strftime` to
-   format the creation time of the record. Otherwise, the ISO8601 format is used.
-   The resulting string is returned.
+   .. method:: format(record)
 
-
-.. method:: Formatter.formatException(exc_info)
-
-   Formats the specified exception information (a standard exception tuple as
-   returned by :func:`sys.exc_info`) as a string. This default implementation just
-   uses :func:`traceback.print_exception`. The resulting string is returned.
+      The record's attribute dictionary is used as the operand to a string
+      formatting operation. Returns the resulting string. Before formatting the
+      dictionary, a couple of preparatory steps are carried out. The *message*
+      attribute of the record is computed using *msg* % *args*. If the
+      formatting string contains ``'(asctime)'``, :meth:`formatTime` is called
+      to format the event time. If there is exception information, it is
+      formatted using :meth:`formatException` and appended to the message. Note
+      that the formatted exception information is cached in attribute
+      *exc_text*. This is useful because the exception information can be
+      pickled and sent across the wire, but you should be careful if you have
+      more than one :class:`Formatter` subclass which customizes the formatting
+      of exception information. In this case, you will have to clear the cached
+      value after a formatter has done its formatting, so that the next
+      formatter to handle the event doesn't use the cached value but
+      recalculates it afresh.
+
+
+   .. method:: formatTime(record[, datefmt])
+
+      This method should be called from :meth:`format` by a formatter which
+      wants to make use of a formatted time. This method can be overridden in
+      formatters to provide for any specific requirement, but the basic behavior
+      is as follows: if *datefmt* (a string) is specified, it is used with
+      :func:`time.strftime` to format the creation time of the
+      record. Otherwise, the ISO8601 format is used.  The resulting string is
+      returned.
+
+
+   .. method:: formatException(exc_info)
+
+      Formats the specified exception information (a standard exception tuple as
+      returned by :func:`sys.exc_info`) as a string. This default implementation
+      just uses :func:`traceback.print_exception`. The resulting string is
+      returned.
 
 
 Filter Objects
 --------------
 
 :class:`Filter`\ s can be used by :class:`Handler`\ s and :class:`Logger`\ s for
 more sophisticated filtering than is provided by levels. The base filter class
 only allows events which are below a certain point in the logger hierarchy. For
 example, a filter initialized with "A.B" will allow events logged by loggers
 "A.B", "A.B.C", "A.B.C.D", "A.B.D" etc. but not "A.BB", "B.A.B" etc. If
 initialized with the empty string, all events are passed.
 
 
 .. class:: Filter([name])
 
    Returns an instance of the :class:`Filter` class. If *name* is specified, it
    names a logger which, together with its children, will have its events allowed
    through the filter. If no name is specified, allows every event.
 
 
-.. method:: Filter.filter(record)
+   .. method:: filter(record)
 
-   Is the specified record to be logged? Returns zero for no, nonzero for yes. If
-   deemed appropriate, the record may be modified in-place by this method.
+      Is the specified record to be logged? Returns zero for no, nonzero for
+      yes. If deemed appropriate, the record may be modified in-place by this
+      method.
 
 
 LogRecord Objects
 -----------------
 
 :class:`LogRecord` instances are created every time something is logged. They
 contain all the information pertinent to the event being logged. The main
 information passed in is in msg and args, which are combined using msg % args to
 create the message field of the record. The record also includes information
 such as when the record was created, the source line where the logging call was
 made, and any exception information to be logged.
 
 
-.. class:: LogRecord(name, lvl, pathname, lineno, msg, args, exc_info)
+.. class:: LogRecord(name, lvl, pathname, lineno, msg, args, exc_info [, func])
 
    Returns an instance of :class:`LogRecord` initialized with interesting
    information. The *name* is the logger name; *lvl* is the numeric level;
-   *pathname* is the absolute pathname of the source file in which the logging call
-   was made; *lineno* is the line number in that file where the logging call is
-   found; *msg* is the user-supplied message (a format string); *args* is the tuple
-   which, together with *msg*, makes up the user message; and *exc_info* is the
-   exception tuple obtained by calling :func:`sys.exc_info()`\ (or :const:`None`,
-   if no exception information is available).
+   *pathname* is the absolute pathname of the source file in which the logging
+   call was made; *lineno* is the line number in that file where the logging
+   call is found; *msg* is the user-supplied message (a format string); *args*
+   is the tuple which, together with *msg*, makes up the user message; and
+   *exc_info* is the exception tuple obtained by calling :func:`sys.exc_info`
+   (or :const:`None`, if no exception information is available). The *func* is
+   the name of the function from which the logging call was made. If not
+   specified, it defaults to ``None``.
+
+   .. versionchanged:: 2.5
+      *func* was added.
+
+
+   .. method:: getMessage()
+
+      Returns the message for this :class:`LogRecord` instance after merging any
+      user-supplied arguments with the message.
+
+
+LoggerAdapter Objects
+---------------------
+
+.. versionadded:: 2.6
+
+:class:`LoggerAdapter` instances are used to conveniently pass contextual
+information into logging calls. For a usage example , see the section on
+`adding contextual information to your logging output`__.
+
+__ context-info_
+
+.. class:: LoggerAdapter(logger, extra)
+
+  Returns an instance of :class:`LoggerAdapter` initialized with an
+  underlying :class:`Logger` instance and a dict-like object.
 
+  .. method:: process(msg, kwargs)
 
-.. method:: LogRecord.getMessage()
+    Modifies the message and/or keyword arguments passed to a logging call in
+    order to insert contextual information. This implementation takes the object
+    passed as *extra* to the constructor and adds it to *kwargs* using key
+    'extra'. The return value is a (*msg*, *kwargs*) tuple which has the
+    (possibly modified) versions of the arguments passed in.
 
-   Returns the message for this :class:`LogRecord` instance after merging any user-
-   supplied arguments with the message.
+In addition to the above, :class:`LoggerAdapter` supports all the logging
+methods of :class:`Logger`, i.e. :meth:`debug`, :meth:`info`, :meth:`warning`,
+:meth:`error`, :meth:`exception`, :meth:`critical` and :meth:`log`. These
+methods have the same signatures as their counterparts in :class:`Logger`, so
+you can use the two types of instances interchangeably.
 
 
 Thread Safety
 -------------
 
 The logging module is intended to be thread-safe without any special work
 needing to be done by its clients. It achieves this though using threading
 locks; there is one lock to serialize access to the module's shared data, and
 each handler also creates a lock to serialize access to its underlying I/O.
 
 
 Configuration
 -------------
 
 
 .. _logging-config-api:
 
 Configuration functions
 ^^^^^^^^^^^^^^^^^^^^^^^
 
-.. % 
-
 The following functions configure the logging module. They are located in the
 :mod:`logging.config` module.  Their use is optional --- you can configure the
 logging module using these functions or by making calls to the main API (defined
 in :mod:`logging` itself) and defining handlers which are declared either in
 :mod:`logging` or :mod:`logging.handlers`.
 
 
 .. function:: fileConfig(fname[, defaults])
 
    Reads the logging configuration from a ConfigParser-format file named *fname*.
    This function can be called several times from an application, allowing an end
    user the ability to select from various pre-canned configurations (if the
@@ -1619,43 +2307,43 @@
    configuration). Defaults to be passed to ConfigParser can be specified in the
    *defaults* argument.
 
 
 .. function:: listen([port])
 
    Starts up a socket server on the specified port, and listens for new
    configurations. If no port is specified, the module's default
    :const:`DEFAULT_LOGGING_CONFIG_PORT` is used. Logging configurations will be
    sent as a file suitable for processing by :func:`fileConfig`. Returns a
    :class:`Thread` instance on which you can call :meth:`start` to start the
    server, and which you can :meth:`join` when appropriate. To stop the server,
-   call :func:`stopListening`. To send a configuration to the socket, read in the
-   configuration file and send it to the socket as a string of bytes preceded by a
-   four-byte length packed in binary using struct.\ ``pack('>L', n)``.
+   call :func:`stopListening`.
+
+   To send a configuration to the socket, read in the configuration file and
+   send it to the socket as a string of bytes preceded by a four-byte length
+   string packed in binary using ``struct.pack('>L', n)``.
 
 
 .. function:: stopListening()
 
-   Stops the listening server which was created with a call to :func:`listen`. This
-   is typically called before calling :meth:`join` on the return value from
+   Stops the listening server which was created with a call to :func:`listen`.
+   This is typically called before calling :meth:`join` on the return value from
    :func:`listen`.
 
 
 .. _logging-config-fileformat:
 
 Configuration file format
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 
-.. % 
-
 The configuration file format understood by :func:`fileConfig` is based on
 ConfigParser functionality. The file must contain sections called ``[loggers]``,
 ``[handlers]`` and ``[formatters]`` which identify by name the entities of each
 type which are defined in the file. For each such entity, there is a separate
 section which identified how that entity is configured. Thus, for a logger named
 ``log01`` in the ``[loggers]`` section, the relevant configuration details are
 held in a section ``[logger_log01]``. Similarly, a handler called ``hand01`` in
 the ``[handlers]`` section will have its configuration held in a section called
 ``[handler_hand01]``, while a formatter called ``form01`` in the
 ``[formatters]`` section will have its configuration specified in a section
 called ``[formatter_form01]``. The root logger configuration must be specified
 in a section called ``[logger_root]``.
@@ -1710,24 +2398,28 @@
 ::
 
    [handler_hand01]
    class=StreamHandler
    level=NOTSET
    formatter=form01
    args=(sys.stdout,)
 
 The ``class`` entry indicates the handler's class (as determined by :func:`eval`
 in the ``logging`` package's namespace). The ``level`` is interpreted as for
 loggers, and ``NOTSET`` is taken to mean "log everything".
 
+.. versionchanged:: 2.6
+  Added support for resolving the handler's class as a dotted module and class
+  name.
+
 The ``formatter`` entry indicates the key name of the formatter for this
 handler. If blank, a default formatter (``logging._defaultFormatter``) is used.
 If a name is specified, it must appear in the ``[formatters]`` section and have
 a corresponding section in the configuration file.
 
 The ``args`` entry, when :func:`eval`\ uated in the context of the ``logging``
 package's namespace, is the list of arguments to the constructor for the handler
 class. Refer to the constructors for the relevant handlers, or to the examples
 below, to see how typical entries are constructed. ::
 
    [handler_hand02]
    class=FileHandler
@@ -1777,25 +2469,215 @@
    level=NOTSET
    formatter=form09
    args=('localhost:9022', '/log', 'GET')
 
 Sections which specify formatter configuration are typified by the following. ::
 
    [formatter_form01]
    format=F1 %(asctime)s %(levelname)s %(message)s
    datefmt=
    class=logging.Formatter
 
 The ``format`` entry is the overall format string, and the ``datefmt`` entry is
-the :func:`strftime`\ -compatible date/time format string. If empty, the package
-substitutes ISO8601 format date/times, which is almost equivalent to specifying
-the date format string "The ISO8601 format also specifies milliseconds, which
-are appended to the result of using the above format string, with a comma
-separator. An example time in ISO8601 format is ``2003-01-23 00:29:50,411``.
-
-.. % Y-%m-%d %H:%M:%S".
+the :func:`strftime`\ -compatible date/time format string.  If empty, the
+package substitutes ISO8601 format date/times, which is almost equivalent to
+specifying the date format string ``"%Y-%m-%d %H:%M:%S"``.  The ISO8601 format
+also specifies milliseconds, which are appended to the result of using the above
+format string, with a comma separator.  An example time in ISO8601 format is
+``2003-01-23 00:29:50,411``.
 
 The ``class`` entry is optional.  It indicates the name of the formatter's class
 (as a dotted module and class name.)  This option is useful for instantiating a
 :class:`Formatter` subclass.  Subclasses of :class:`Formatter` can present
 exception tracebacks in an expanded or condensed format.
 
+
+Configuration server example
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Here is an example of a module using the logging configuration server::
+
+    import logging
+    import logging.config
+    import time
+    import os
+
+    # read initial config file
+    logging.config.fileConfig("logging.conf")
+
+    # create and start listener on port 9999
+    t = logging.config.listen(9999)
+    t.start()
+
+    logger = logging.getLogger("simpleExample")
+
+    try:
+        # loop through logging calls to see the difference
+        # new configurations make, until Ctrl+C is pressed
+        while True:
+            logger.debug("debug message")
+            logger.info("info message")
+            logger.warn("warn message")
+            logger.error("error message")
+            logger.critical("critical message")
+            time.sleep(5)
+    except KeyboardInterrupt:
+        # cleanup
+        logging.config.stopListening()
+        t.join()
+
+And here is a script that takes a filename and sends that file to the server,
+properly preceded with the binary-encoded length, as the new logging
+configuration::
+
+    #!/usr/bin/env python
+    import socket, sys, struct
+
+    data_to_send = open(sys.argv[1], "r").read()
+
+    HOST = 'localhost'
+    PORT = 9999
+    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    print "connecting..."
+    s.connect((HOST, PORT))
+    print "sending config..."
+    s.send(struct.pack(">L", len(data_to_send)))
+    s.send(data_to_send)
+    s.close()
+    print "complete"
+
+
+More examples
+-------------
+
+Multiple handlers and formatters
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Loggers are plain Python objects.  The :func:`addHandler` method has no minimum
+or maximum quota for the number of handlers you may add.  Sometimes it will be
+beneficial for an application to log all messages of all severities to a text
+file while simultaneously logging errors or above to the console.  To set this
+up, simply configure the appropriate handlers.  The logging calls in the
+application code will remain unchanged.  Here is a slight modification to the
+previous simple module-based configuration example::
+
+    import logging
+
+    logger = logging.getLogger("simple_example")
+    logger.setLevel(logging.DEBUG)
+    # create file handler which logs even debug messages
+    fh = logging.FileHandler("spam.log")
+    fh.setLevel(logging.DEBUG)
+    # create console handler with a higher log level
+    ch = logging.StreamHandler()
+    ch.setLevel(logging.ERROR)
+    # create formatter and add it to the handlers
+    formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+    ch.setFormatter(formatter)
+    fh.setFormatter(formatter)
+    # add the handlers to logger
+    logger.addHandler(ch)
+    logger.addHandler(fh)
+
+    # "application" code
+    logger.debug("debug message")
+    logger.info("info message")
+    logger.warn("warn message")
+    logger.error("error message")
+    logger.critical("critical message")
+
+Notice that the "application" code does not care about multiple handlers.  All
+that changed was the addition and configuration of a new handler named *fh*.
+
+The ability to create new handlers with higher- or lower-severity filters can be
+very helpful when writing and testing an application.  Instead of using many
+``print`` statements for debugging, use ``logger.debug``: Unlike the print
+statements, which you will have to delete or comment out later, the logger.debug
+statements can remain intact in the source code and remain dormant until you
+need them again.  At that time, the only change that needs to happen is to
+modify the severity level of the logger and/or handler to debug.
+
+
+Using logging in multiple modules
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+It was mentioned above that multiple calls to
+``logging.getLogger('someLogger')`` return a reference to the same logger
+object.  This is true not only within the same module, but also across modules
+as long as it is in the same Python interpreter process.  It is true for
+references to the same object; additionally, application code can define and
+configure a parent logger in one module and create (but not configure) a child
+logger in a separate module, and all logger calls to the child will pass up to
+the parent.  Here is a main module::
+
+    import logging
+    import auxiliary_module
+
+    # create logger with "spam_application"
+    logger = logging.getLogger("spam_application")
+    logger.setLevel(logging.DEBUG)
+    # create file handler which logs even debug messages
+    fh = logging.FileHandler("spam.log")
+    fh.setLevel(logging.DEBUG)
+    # create console handler with a higher log level
+    ch = logging.StreamHandler()
+    ch.setLevel(logging.ERROR)
+    # create formatter and add it to the handlers
+    formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")
+    fh.setFormatter(formatter)
+    ch.setFormatter(formatter)
+    # add the handlers to the logger
+    logger.addHandler(fh)
+    logger.addHandler(ch)
+
+    logger.info("creating an instance of auxiliary_module.Auxiliary")
+    a = auxiliary_module.Auxiliary()
+    logger.info("created an instance of auxiliary_module.Auxiliary")
+    logger.info("calling auxiliary_module.Auxiliary.do_something")
+    a.do_something()
+    logger.info("finished auxiliary_module.Auxiliary.do_something")
+    logger.info("calling auxiliary_module.some_function()")
+    auxiliary_module.some_function()
+    logger.info("done with auxiliary_module.some_function()")
+
+Here is the auxiliary module::
+
+    import logging
+
+    # create logger
+    module_logger = logging.getLogger("spam_application.auxiliary")
+
+    class Auxiliary:
+        def __init__(self):
+            self.logger = logging.getLogger("spam_application.auxiliary.Auxiliary")
+            self.logger.info("creating an instance of Auxiliary")
+        def do_something(self):
+            self.logger.info("doing something")
+            a = 1 + 1
+            self.logger.info("done doing something")
+
+    def some_function():
+        module_logger.info("received a call to \"some_function\"")
+
+The output looks like this::
+
+    2005-03-23 23:47:11,663 - spam_application - INFO -
+       creating an instance of auxiliary_module.Auxiliary
+    2005-03-23 23:47:11,665 - spam_application.auxiliary.Auxiliary - INFO -
+       creating an instance of Auxiliary
+    2005-03-23 23:47:11,665 - spam_application - INFO -
+       created an instance of auxiliary_module.Auxiliary
+    2005-03-23 23:47:11,668 - spam_application - INFO -
+       calling auxiliary_module.Auxiliary.do_something
+    2005-03-23 23:47:11,668 - spam_application.auxiliary.Auxiliary - INFO -
+       doing something
+    2005-03-23 23:47:11,669 - spam_application.auxiliary.Auxiliary - INFO -
+       done doing something
+    2005-03-23 23:47:11,670 - spam_application - INFO -
+       finished auxiliary_module.Auxiliary.do_something
+    2005-03-23 23:47:11,671 - spam_application - INFO -
+       calling auxiliary_module.some_function()
+    2005-03-23 23:47:11,672 - spam_application.auxiliary - INFO -
+       received a call to "some_function"
+    2005-03-23 23:47:11,673 - spam_application - INFO -
+       done with auxiliary_module.some_function()
+
