When I run phpinfo() and look by the Configuration category under PHP Core, I see a directive titled include_path, with a local value and a master value.
In this case, my local value is set to
.: ./include: ../include: /usr/share/php: /usr/share/php/smarty: /usr/share/pear
and my master value is set to
.: /usr/share/php: /usr/share/pear: /usr/share/php/pear: /usr/share/php/smarty
The reason I am trying to learn how this works is because there is a file in the system I am working on titled Smarty.class.php, which I'm sure sounds very familiar to anyone who uses Smarty Templating Engine.
One of the PHP files has the following includes:
require_once("Smarty.class.php");
require_once("user_info_class.inc");
The file user_info_class.inc is in the same directory as the file making the include, which makes perfect sense to me, and is the way that I've always referenced files. I decided that I wanted to open up the Smarty.class.php file and had assumed it would be in the same directory, but it was not.
After doing a bit of digging, I discovered those php_ini variables, and was finally able to locate the file in the directory usr/share/php/smarty/.
So it would seem that when making an include, it follows some sort of order between the Local and Master values for the include_path.
Assuming that my deductions were correct thus far, can someone explain the order in which PHP searches for the files to be included?