You must be an administrator or root user, also called superuser, to execute many of the commands used to manage a server.
For example, if you’re not an administrator or a root user, entering the shutdown
command gives you an error:
How to open apps not from Mac App Store. Sudo spctl -master-disable. Now press Return, and you will be asked to enter your password. Once that's done, open System Preferences (if it's already. This is only for the apps being blocked by security and not opening after allowing as well. Disable the block. Sudo spctl -master-disable Launch the app and allow the update to complete then re-enable the block. I bet this will also resolve other software not opening as well. Sudo spctl -master-enable. To resolve Gatekeeper issues on macOS Sierra and unlock images and programs ( annoying image/application is damaged messages pretending you cannot open things ). For that reason you might have to completely disable Gatekeeper checks, and to do that open your terminal and type: sudo spctl -master-disable.Enter your password and you’re done.
This is because the shutdown
command can be run only by the root user or by an administrator user with root user privileges.
To run commands with superuser privileges, use the sudo
command. sudo
stands for superuser do.
The following example works on computers with macOS installed, so don’t run it unless you want to restart your computer:
% sudo shutdown
You’re asked for the password of the current user.
Only administrator users can use sudo
. If you’re not logged in as an administrator, you can do so by entering the following command, where adminUsername is the name of an administrator user:
You’re asked to enter the password for adminUsername, after which a new shell is opened for that user.
If a command requires it, you can use su
to switch to the root user. Under normal circumstances, you shouldn’t log in as the root user.
Important: If you use su
to log in as the root user, be especially careful, because you have sufficient privileges to make changes that can cause your computer to stop working.