I want Emulate.pm's logging behavior to be determined by the Log4perl conf file of the program calling on Emulate.pm.

If Emulate.pm isn't doing anything OO-ish then something like the following should work (untested):

package Emulate;
use Log::Log4perl;

my  $Logger = Log::Log4perl->get_logger(  __PACKAGE__ );

...

sub something_that_needs_to_log {
  $Logger->info('Foo');
}
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If Emulate.pm is implementing a class, especially one that's likely to be subclassed, you need to be a little bit more careful about just using __PACKAGE__ as the logging category passed to get_logger(). See the section "Pitfalls with Categories" in the Log::Log4perl docs for more info.