program start -> initialize logger <<Log::Log4perl::init("log.properties")>> -> get the logger <<my $logger = get_logger()>> -> use fork() to create threads -> wait for threads to die

##</code><code>##

child start -> change NDC <<Log::Log4perl::NDC->push($NDC)>> -> do their thing, including using customer modules

##</code><code>##

use Log::Log4perl (get_logger);
my $logger = get_logger();
sub sayHello
{
  $logger->info("Hello world!");
}