PHP Atomic file put content

file_put_contents_atomic.php

function file_put_contents_atomic($filename, $content) {

    $temp = tempnam(FILE_PUT_CONTENTS_ATOMIC_TEMP, 'temp');
    if (!($f = @fopen($temp, 'wb'))) {
        $temp = FILE_PUT_CONTENTS_ATOMIC_TEMP . DIRECTORY_SEPARATOR . uniqid('temp');
        if (!($f = @fopen($temp, 'wb'))) {
            trigger_error("file_put_contents_atomic() : error writing temporary file '$temp'", E_USER_WARNING);
            return false;
        }
    }

    fwrite($f, $content);
    fclose($f);

    if (!@rename($temp, $filename)) {
        @unlink($filename);
        @rename($temp, $filename);
    }

    @chmod($filename, FILE_PUT_CONTENTS_ATOMIC_MODE);

    return true;

}