override php disable_function per account

Sometimes user needs functions like exec and proc_open etc which are required by their application but they are security risk for all other account. Currently, the only way is to allow the function use server wide per php version. If we have an ability to overide php disable function per account, so we can allow certain functions just for that account instead of allowing it for all.

As a web-hosting provider, I would like new feature to override php disable_function, so that functions which are needed per account can be allowed, and kept disable serverwide