My normal OS X account is not the "Administrator" account. For daily use, I want as much protection as possible so that I don't screw up the system. However, there are times when I need Admin privileges or even root privileges. In the past, I used to logout of my user account and login to my Admin account to perform these tasks.
I've discovered an easier way for simple jobs. Since OS X is a true multiuser system I can be logged in more than once at the same time! I open a terminal window and from my user prompt, I type login admin_name where admin_name is the name of my Admin account. I then enter my Admin password when prompted and voila, I'm logged in as the Administrator.
From there, I can do anything I want with all of the privileges of my Admin account. And if I need temporary root privileges, I can use sudo. All the while, of course, I am still logged into the GUI with my normal user account.
When you are done in the terminal, type 'exit' or 'logout' to sequentially log out of each account that was logged in.
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