Question

What is set_include_path Relative to, in PHP? Is it the folder where the PHP.exe resides? Is it the webroot? In other words, what folder would set_include_path(‘/’) or set_include_path(‘.’) be referring to?

Answer 1

Relative paths are resolved from the location of the file where include or another function that uses include_path is used in (see description of include_path):

Using a . in the include path allows for relative includes as it means the current directory. However, it is more efficient to explicitly use include './file' than having PHP always check the current directory for every include.

/ would describe the root of your filesystem and . the current directory.