security - Is there an exhaustive list of functions that can be disabled using disable_functions in PHP?

I have always wondered if there is an exhaustive list of functions that could be disabled using disable_functions in php.ini?

I question if there is a specific list that can vs can't be because PHP.net says:

This directive allows you to disable certain functions for security reasons.

It reads like there are certain functions that can be. And certain functions that can't be.