[log4perl-devel] Log::Log4perl Recipe of the Week (#10)

[<log...@pe...>]

Welcome to the Log::Log4perl recipe of the week. Today:

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Log::Log4perl Recipe of the Week (#10):

What's the easiest way to turn off all logging, even with a
lengthy Log4perl configuration file?
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In addition to category-based levels and appender
thresholds, Log::Log4perl supports system-wide logging
thresholds. This is the minimum level the system will
require of any logging events in order for them to make it
through to any configured appenders.

For example, putting the line

    log4perl.threshold = ERROR

anywhere in your configuration file will limit any output to
any appender to events with priority of ERROR or higher
(ERROR or FATAL that is).

However, in order to suppress all logging entirely, you need
to use a priority that's higher than FATAL: It is simply
called "OFF", and it is never used by any logger. By
definition, it is higher than the highest defined logger
level.

Therefore, if you keep the line

    log4perl.threshold = OFF

somewhere in your Log::Log4perl configuration, the system
will be quiet as a graveyard. If you deactivate the line
(e.g. by commenting it out), the system will, upon config
reload, snap back to normal operation, providing logging
messages according to the rest of the configuration file
again.


Have fun! Until next week.

-- Mike

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# Mike Schilli                    #
# log...@pe...        #
# http://perlmeister.com          #
# http://log4perl.sourceforge.net #
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