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=item Log File Permissions

If the process is started as root but later drops permissions to a
non-priviledged user for security purposes, it's important that 
logfiles are created with correct permissions.

If they're created as root when the program starts, the non-priviledged
user won't be able to write to them later (unless they're world-writable
which is also undesirable because of security concerns).

The best strategy to handle this case is to specify the non-priviledged
user as the owner of the logfile in the Log4perl configuration:

    log4perl.logger = DEBUG, FileApp
    log4perl.appender.FileApp = Log::Log4perl::Appender::File
    log4perl.appender.FileApp.filename = /var/log/foo-app.log
    log4perl.appender.FileApp.owner    = nobody
    log4perl.appender.FileApp.layout   = PatternLayout
    log4perl.appender.FileApp.layout.ConversionPattern = %d %m%n

This way, the process starts up as root, creates the logfile if it 
doesn't exist yet, and changes its owner to 'nobody'. Later, when the
process assumes the identity of the user 'nobody', it will continue
to write to the logfile without permission problems.

=item Log4perl Categories

Note that App::Daemon is logging messages in Log4perl's App::Daemon 
namespace. So, if you're running your own Log4perl configuration and
define a root logger like

    log4perl.logger=DEBUG, appendername

then App::Daemon's messages will bubble up to it and be visible in
the output. If you don't want that, either use

    log4perl.logger.My.App=DEBUG, appendername

to explicitly enable verbose logging in your application namespace
(and not in App::Daemon's) or tone down App::Daemon's verbosity via

    log4perl.logger.App.Daemon=ERROR

explicitly. If you want more details on basic Log4perl features,
check out the L<Log::Log4perl> manual page.

=back

=head2 Detach only

If you want to create a daemon without the fancy command line parsing
and PID file checking functions, use

    use App::Daemon qw(detach);
    detach();
    # ... some code here

This will fork a child, terminate the parent and detach the child from
the terminal. Issued from the command line, the program above will
continue to run the code following the detach() call but return to the
shell prompt immediately.

=head1 AUTHOR

    2008, Mike Schilli <cpan@perlmeister.com>
    
=head1 LICENSE

Copyright 2008-2012 by Mike Schilli, all rights reserved.
This program is free software, you can redistribute it and/or
modify it under the same terms as Perl itself.