當我把電腦系統升級到OS10.11之後cocoapods不好用了，各種錯誤，各種不對，卸載重裝依然有一些問題，在經歷各種試探和搜索之後找到合適的解決方法，記錄下來以便爲以後做參考。
原文地址：http://stackoverflow.com/questions/30812777/cannot-install-cocoa-pods-after-uninstalling-results-in-error/30851030#30851030
Answer：
As it has been pointed out below, this is a cleaner way of doing it, instead of getting around the Security features of OS X.
sudo gem install -n /usr/local/bin cocoapodsOriginal Answer
I'm assuming you're running OS X 10.11.
This is happening because Apple has enabled rootless on the new install.
If you type:
sudo nvram boot-args="rootless=0"; sudo reboot
in terminal.app,
your computer will reboot with it disabled.
Once that is done, type:
sudo gem install cocoapods -V
the -V is
for verbose and will spit out any errors if they happen.