Would be nice to have a built-in function for preventing Directory Traversal Attacks

[Patchx]

Description

I apologize if this is a duplicate. I searched a bit but didn't see this topic existing in the issues.

Given the potential security impact of a file_get_contents, unlink, etc call without directory traversal attack prevention, it would be nice to have some built-in protection, either in the form of a parameter to these existing types of functions, or a dedicated checker function, such as that described in https://stackoverflow.com/questions/4205141/preventing-directory-traversal-in-php-but-allowing-paths

It's not hard to implement this per-project, but having something built-in would help more projects have better security hygiene by default.