define("LOGGER_DEFAULT_LOG_FILE","/path/to/app/log/log");
define("LOGGER_DEFAULT_NOTIFY_EMAIL","webmaster@example.com");

$logger = new Logger("import_articles");

// do something

$logger->info("Total articles to import ".sizeof($articles));

// in order to write buffered messages to a file, just call flush() method
$logger->flush();

// a the end of a script call flushAll();
$logger->flushAll();

Levels of messages importance

$logger->debug("some debug information");
$logger->info("a message");
$logger->warn("a warning");
$logger->error("error message");
$logger->security("a security message");