There are a lot of questions about how to get extension X for PHP Version Y on Linux Distro Z running.
What I'm missing out there are comprehensive general tutorials about how PHP on Linux works.
As an example: I am currently trying to get mysqli working and I know I can either compile PHP with mysqli or include the extension. Well yeah, but how do I exactly compile PHP with a certain extension, where do I get the necessary files for my Linux Distro and if I want to include it as extension.so, where do I get this? Also if I look at my phpInfo() I see that PHP 5.2.14 is running but if I do yum info php, it tells me that the version is PHP 5.1.6. How come, do I have two differen PHP versions running, what would I do to get clarity into this... etc.
What I need is a clear description of the general mechanisms, something like a tutorial called: How to enable PHP extensions on Linux servers.
Any part-tutorials or links to such things are greatly appreciated!