I want to disable some functions on server to improve security of server. I followed these steps:

**STEP: 1**
Open `php.ini` file:
 `vi /etc/php.ini`

**STEP: 2**
Find `disable_functions` and set new list as follows:
 disable\_functions= exec,passthru,shell\_exec,system

**STEP: 3**
 service httpd restart

With the help of above steps I am able to disable all the above functions. Now these functions are no longer available on server. 

If I want to enable or disable these functions for particular directories then it is possible or not?