mac에서 brew update 오류를 보고합니다. Error: 해결 및 brew 업그레이드

rm -rf /usr/local/etc/bash_completion.d/brew
rm -rf /usr/local/share/zsh/site-functions/_brew
rm -rf /usr/local/share/man/man1/brew.1
rm -rf /usr/local/share/doc/homebrew

brew update

ymdeMacBook-Pro:~ ym$ brew update

Already up-to-date.

brew update          #   Homebrew  
brew outdated        #  
brew upgrade    #  ， 

brew upgrade; brew cleanup    #  ，