~ # php -v
PHP 7.4.33 (cli) (built: Nov  2 2022 16:00:55) ( ZTS Visual C++ 2017 x64 )
Copyright (c) The PHP Group
Zend Engine v3.4.0, Copyright (c) Zend Technologies

~ # php -a
Interactive shell

php > print mb_strtoupper("äöüß");
ÄÖÜSS
php >