$ homebrew updateがうまく実行されなかったので、メモします。 homebrewをアップデートしようとすると、 /usr/local/Library/brew.rbのpermissionが原因で、実行できない。 $ brew update /usr/local/bin/brew: line 28: /usr/local/Library/brew.rb: Permission denied /usr/local/bin/brew: line 28: exec: /usr/local/Library/brew.rb: cannot execute: Undefined error: 0
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