func.php

<?php

function write_php_ini($array, $file)
{
    $res = array();
    foreach ($array as $key => $val) {
        if (is_array($val)) {
            $res[] = "[$key]";
            foreach ($val as $skey => $sval) $res[] = "$skey = " . (is_numeric($sval) ? $sval : '"' . $sval . '"');
        } else $res[] = "$key = " . (is_numeric($val) ? $val : '"' . $val . '"');
    }
    safe_file_rewrite($file, implode("\r\n", $res));
}

function safe_file_rewrite($fileName, $dataToSave)
{
    if ($fp = fopen($fileName, 'w')) {
        $startTime = microtime(TRUE);
        do {
            $canWrite = flock($fp, LOCK_EX);
            // If lock not obtained sleep for 0 - 100 milliseconds, to avoid collision and CPU load
            if (!$canWrite) usleep(round(rand(0, 100) * 1000));
        } while ((!$canWrite) and ((microtime(TRUE) - $startTime) < 5));

        //file was locked so now we can store information
        if ($canWrite) {
            fwrite($fp, $dataToSave);
            flock($fp, LOCK_UN);
        }
        fclose($fp);
    }
}