php 및 mysql 변경 후 에러 어떻게 해결해야 하나요? 채택완료

웹호스팅 업체 미리내에 요청했어요.

php 5.5 / mysql 5.5 이 부분을 

php 7.2 /mariadb 10.4 이렇게 변경했습니다.

그런데 아래와 같은 에러가 발생합니다.

어떻게 해결을 해야하나요

감사합니다.

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 45

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 45

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 80

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 80

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 82

Warning: Use of undefined constant file - assumed 'file' (this will throw an Error in a future version of PHP) in /web/home/kht/html/theme/purewhite_wide/skin/board/product/view.skin.php on line 82