| UserDB (bool verbose) | UserDB | 
| ~UserDB () | ~UserDB | 
| User*  add_user (uid_t user_id, const string& username, gid_t gid) | add_user | 
| void  load_password_file () | load_password_file | 
| const User*  find_user_by_user_id (uid_t user_id) | find_user_by_user_id | 
| void  remove_user (uid_t user_id) | remove_user | 
| bool  has_capability (uid_t user_id, const string& capability) | has_capability |