function add_text_to_file($file, $text, $replace = false) {
	if(file_exists($file) and is_writable($file)) {
		$filecontents = file($file);
		$fout = fopen($file, "w");

		$filecontents = array_map('rtrim', $filecontents);
		array_push($filecontents, $text);
		if ($replace)
			$filecontents = array_unique($filecontents);

		$file_text = implode("\n", $filecontents);

		fwrite($fout, $file_text);
		fclose($fout);
		return true;
	} else {
		return false;
	}
}