How to check if there are multiple versions of PHP installed on Ubuntu 12.04 LTS?
To check your installed versions type:
cd /etc/php
in your terminal to go to the configuration folder of your PHP installations and then you type:
ls
The output will be the folders that corresponds to the versions installed in your machine. In my case the command outputs:
5.6 7.0 7.1
I use the following command to view installed PHP versions in Ubuntu:
sudo update-alternatives --list php
Second way go to php directory where all PHP version configuration file stored:
cd /etc/php
dir
Output:
> 5.6 7.0 7.1
Since you have a Linux environment, you can run this on your console:
locate bin/php
And then for anything that looks like a PHP binary, get the version. The output for me for the above is:
/home/xx/Development/Personal/Project1/webapp/bin/phpunit
/home/xx/Development/Personal/Project1/webapp-backup/vendor/bin/phpunit
/home/xx/Development/Personal/Project2/app/vendor/bin/phpunit
/home/xx/php-threaded/bin/php
/home/xx/php-threaded/bin/php-cgi
/home/xx/php-threaded/bin/php-config
/home/xx/php-threaded/bin/phpize
/usr/bin/php
/usr/bin/php5
/usr/local/bin/php-cgi
/usr/local/bin/php-config
/usr/local/bin/php53
/usr/local/bin/phpize
/usr/sbin/php5dismod
/usr/sbin/php5enmod
/usr/sbin/php5query
Out of those, there are a few that look like PHP binaries. So let's get the version for each:
/home/xx/php-threaded/bin/php -v
/usr/bin/php -v
/usr/bin/php5 -v
/usr/local/bin/php53 -v
That will give you the versions of PHP you have installed.
I wouldn't bother deleting an old version, it might remove files that will stop things working. You can just configure the console version, or the Apache version, to use the version you want.
In answer to your supplementary question: it seems that you've followed the instructions here to add an unofficial repo to your version of Ubuntu, since the standard repo does not support 5.5.
We discovered together that the way to get it working was first to upgrade Apache from 2.2 to 2.4:
sudo apt-get upgrade apache2
It should be noted that this can cause some vhost repair to be required, as some Apache directives changed in this version. Once you have done that, you can get the new version of mod_php:
sudo apt-get install libapache2-mod-php5