tail -f debug.log to read the log from terminal

debug_log.php

/**
 * php line debug
 */
function debug_log($data) {
    $filename = realpath(__DIR__ . './debug.log');
    if (!file_exists($filename) || !is_writable($filename)) {
        return;
    }

    file_put_contents($filename, sprintf("[%s] %s \n",
        date('m-d-Y h:i:s', time()),
        trim(var_export($data, true), "'")
    ), FILE_APPEND);
}