# Direct
sudo update-alternatives --set php /usr/bin/php7.4
sudo update-alternatives --set php /usr/bin/php8.0
sudo update-alternatives --set php /usr/bin/php8.1
# To ask:
sudo update-alternatives --config php
# To show current
sudo update-alternatives --query phpThere are 3 choices for the alternative java (providing /usr/bin/java).
Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 auto mode
1 /usr/bin/gij-4.4 1044 manual mode
2 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 manual mode
3 /usr/lib/jvm/java-6-sun/jre/bin/java 63 manual mode
Press enter to keep the current choice[*], or type selection number: