Upgrade PHP 5.4 to PHP 5.5 on Ubuntu Server 12.10
By Shay Anderson on April 2014
Here are directions on how to upgrade from PHP 5.4 to PHP 5.5 on Ubuntu Server (12.10 in this example). Warning: the following instructions modify system settings and packages, make sure you know what you are doing before proceeding!

First, run update and install the package software-properties-common: # apt-get update && apt-get install software-properties-common
Next, add repo: # add-apt-repository ppa:ondrej/php5If you encounter an error and can’t add the repo try: # apt-get install python-software-properties
Finally, update the system and PHP 5.4 to PHP 5.5: # apt-get update && sudo apt-get dist-upgradeAfter finished restart Apache to make sure configuration file is working: # service apache2 restart

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