FileUploader::saveUploadedPartLocal

static function saveUploadedPartLocal($fileName, $data)
{
	$result = new Result();

	$file = new BitrixMainIOFile($fileName);
	if(!static::isCorrectFile($file))
	{
		$result->addError(new Error('Wrong fileName'));
	}
	if(!$file->putContents($data, BitrixMainIOFile::APPEND))
	{
		$result->addError(new Error('Cant write local file'));
	}

	return $result;
}