brew install XXX错误

brew提示错误：

Error: The following directories are not writable by your user:
/usr/local/share/man/man3
/usr/local/share/man/man7

You should change the ownership of these directories to your user.
  sudo chown -R $(whoami) /usr/local/share/man/man3 /usr/local/share/man/man7

And make sure that your user has write permission.
  chmod u+w /usr/local/share/man/man3 /usr/local/share/man/man7

按照终端提示，我尝试了一下

1. 终端输入sudo chown -R `whoami`:admin /usr/local/bin
2. 系统提示输入密码，输入密码
3. 终端输入 输入sudo chown -R `whoami`:admin /usr/local/share

brew install xxx可以正常使用