Quick write to file with date/time, very crude.

gistfile1.php

function logToFile($msg) { 
        $filename = 'logfile.log';
        
        if(is_array($msg)){
                file_put_contents($filename, print_r($msg, true), FILE_APPEND);
        } else {
                $fd = fopen($filename, "a");
                $str = "[" . date("Y/m/d h:i:s", mktime()) . "] " . $msg; 
                fwrite($fd, $str . "\n");
                fclose($fd);
        }
}