code: private static function findLsof()
      {
          $finder = new ExecutableFinder();
          $lsofPath = $finder->find('lsof', null, ['/sbin', '/usr/sbin']);
          if ($lsofPath === null) {
              throw new Exception\RuntimeException('Unable to find the "lsof" executable.');
          }
  
          return $lsofPath;
      }
docs: @throws Exception\RuntimeException
  
  @return string