走过岁月......

在mac下执行brew update时出现以下错误提示

MacPC:~ liuxin$ brew update

Error: /usr/local must be writable!

以前一直默认用的好好的,突然出现这种情况导致不能正常使用,下面详细排查

MacPC:~ liuxin$ brew doctor

Please note that these warnings are just used to help the Homebrew maintainers

with debugging if you file an issue. If everything you use Homebrew for is

working fine: please don't worry and just ignore them. Thanks!

Warning: /usr/local is not writable.

You should probably change the ownership and permissions of /usr/local

back to your user account.

  sudo chown -R $(whoami) /usr/local

Warning: /usr/local is not writable.

Even if this directory was writable when you installed Homebrew, other

software may change permissions on this directory. For example, upgrading

to OS X El Capitan has been known to do this. Some versions of the

"InstantOn" component of Airfoil or running Cocktail cleanup/optimizations

are known to do this as well.

You should probably change the ownership and permissions of /usr/local

back to your user account.

  sudo chown -R $(whoami) /usr/local

Error: Failure while executing: /usr/bin/otool -L /usr/bin/install_name_tool

解决方法

根据上面的提示,执行以下命令

MacPC:~ liuxin$ sudo chown -R $(whoami) /usr/local

Password:

测试效果

MacPC:~ liuxin$ brew update

==> Installing git dependency: cctools

......

成功