Security on External HDD

[Souma]

Is there a way to check if external hard disk is plug in?

 

Coz what i'm trying to do here is, i'm creating a small app which protects the folder on the external hard disk. The app itself is on the external hard disk, so when non-authorized person try to access to the folder which is protected it will denied it.

 

Main points:

- The app is on the external hard disk

- How do i code the part when user try to access to a restricted folder, the app runs itself and check for authentication (pass key, let say it prompt user).

- Setting folder security attributes

 

Guide me pls~