更新cocoa pods 报错ERROR: While exe

1.今天update pod的时候报错,错误信息
[!] The master repo requires CocoaPods 1.0.0 - (currently using 0.39.0)

2.执行sudo gem update cocoapods 命令更新又报错.
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/xcodeproj

3.Google了一下执行下列命令
sudo gem install -n /usr/local/bin cocoa pods
更新成功。

                                                  完。