Why is filter_input() incomplete?

Question

I am working a lot on a PHP-based CMS at the moment, and while I\'m at it I would like to move all the handling and sanitation of user input to one central place. (At the mo

Answer 1

"input filtering" or "sanitation" is an absurd idea. Stay away from it.

Explanations and further discussion

What's the best method for sanitizing user input with PHP?

What else should I be doing to sanitize user input?