/**
  * Writes a content in a local path and returns written length
  *
  * @param string $path
  * @param \MarkdownExtended\API\ContentInterface $content
  *
  * @return int
  */
 protected function writeOutputFile($path, ContentInterface $content)
 {
     // construct output file name
     $name = $content->getMetadata('file_name');
     $path = Helper::fillPlaceholders($path, !empty($name) ? pathinfo($name, PATHINFO_FILENAME) : Helper::header2Label($content->getTitle()));
     // make a backup if `option[force]!==true`
     $backup = (bool) $this->getKernel()->getConfig('force') !== true;
     // write output
     Helper::writeFile($path, (string) $content, $backup);
     // return created path
     return $path;
 }