I can't install zsh with Homebrew

Question

OS X El Capitan version 10.11.2

I attempted brew update, but this error message is displayed.

/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require': cannot load such file -- mach (LoadError)
    from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/Library/Homebrew/extend/pathname.rb:2:in `<top (required)>'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/Library/Homebrew/global.rb:3:in `<top (required)>'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/Library/brew.rb:15:in `<main>'

I also attempted brew install zsh, but the above message is displayed.

Please let me know how to fix this error message.

Looks like your version of ruby is too old or your install of brew is broke. — bmargulies, Feb 28 '16 at 14:36
Your version of Ruby is fine. Does the `brew update` error happens again if you run `brew update` a second time? — bfontaine, Feb 29 '16 at 10:15
i'm facing the same issue. although brew was working fine with me before. i'm guessing it happened after i upgraded my system to El Capitan. — dima, Mar 03 '16 at 11:55

score 4 · Answer 1 · edited May 23 '17 at 11:51

Found an answer which worked for me here: https://stackoverflow.com/a/35495897/1354137

The problem mainly occurs after updating OS X to El Capitan (OS X 10.11). This is mainly because of file permission issues with file El Capitan’s new SIP process. Try changing permissions of /usr/local directory.
$ sudo chown -R $(whoami):admin /usr/local  
If it still doesn't work, use following steps and everything will be fine. This may be because homebrew is not updated.
1. open terminal  
2. $ cd /usr/local  
3. $ git reset --hard  
4. $ git clean -df
5. $ brew update

I can't install zsh with Homebrew

1 Answers1