The configuration of PHP is typically done in the php.ini file. The php.ini file is a crucial configuration file for PHP. It contains various settings that govern how PHP behaves on your server. These settings can control everything from resource limits to security features and performance optimizations.

Enabling short open tags in PHP allows developers to use the <? and <? ?> tags as shorthand for <?php ?>.

To enable short open tags follow these general steps.

Enable short open tags

Find out php.ini location.

php --ini

Edit php.ini

Syntax

sudo nano /etc/php/<version>/cli/php.ini

Example

sudo nano /etc/php/8.1/cli/php.ini

Setting short_open_tag to On in the PHP configuration allows PHP code to be written with short tags (<? ?>) instead of the standard <?php ?> tags.

short_open_tag = On

To apply the changes, you need to restart the Apache web server.

sudo service apache2 restart

Possible issue

If the previous steps don’t work, try this.

Change permissions to full access to everyone.

sudo chmod -R 777 /etc/php/8.1/apache2

or use a safer approach to limit permissions to access the files within the apache2 directory. Then verify if the change has taken effect.

sudo chmod -R 644 /etc/php/8.1/apache2/php.ini

Edit php.ini file.

sudo nano /etc/php//apache2/php.ini

Set short_open_tag to On

short_open_tag = On

Restart Apache service

sudo service apache2 restart