php - Relative include files

Question

I have a file

workers/activity/bulk_action.php which includes a file

include('../../classes/aclass.php');

Inside aclass.php it does:

include ('../tcpdf/config/lang/eng.php');

It seems that the include in the second file is using the first files working directory instead of being relative to itself, resulting in an error. How does this work?

Answer 1

You can adapt the second include with:

include (__DIR__.'/../tcpdf/config/lang/eng.php');

The magic constant __DIR__ refers to the current .php file, and by appending the relative path after that, will lead to the correct location.

But it only works since PHP5.3 and you would have to use the dirname(__FILE__) construct instead if you need compatibility to older setups.