logger

$filter_crlf = array("\n", "\r");
$message = date("Y-m-d H:i:s")." : ".$message;
$mesg = str_replace($filter_crlf,'',$message);
$mesg .= "\n";
$logfile = DOCROOT."application/logs/upgrade_".$this->session->get('upgrade_session').".txt";
$logfile = fopen($logfile, 'a+');
fwrite($logfile, $mesg);
fclose($logfile);