After upgrading the mac system, brew reported an error and reinstalled homebrew
Brew reported an error after upgrading the mac system
Brew update
Error: Running Homebrew as root is extremely dangerous and no longer supported.
As Homebrew does not drop privileges on installation you would be giving all
Build scripts full access to your system.
Just reinstall a new version of brew
Mkdir homebrew & & curl-L https://github.com/Homebrew/brew/tarball/master | tar xz-- strip 1-C homebrew