DocumentController::getFileSrcToPublish

protected function getFileSrcToPublish()
{
	if($this->isSpecificVersion())
	{
		$fileId = $this->version->getFileId();
	}
	else
	{
		$fileId = $this->file->getFileId();
	}
	$fileArray = CFile::makeFileArray($fileId);
	if(!is_array($fileArray))
	{
		return null;
	}

	return $fileArray['tmp_name'];
}