今天用pod install时出现错误：
The `master` repo requires CocoaPods
0.29.0
但是，终端gem update CocoaPods 显示
Updating installed gems
Nothing to
update
原因是gem版本不支持升级至0.29.0
具体见：http://stackoverflow.com/questions/16511705/the-master-repo-requires-cocoapods-0-18-1
解决步骤如下：
sudo
gem update
sudo gem install CocoaPods
The `master` repo requires CocoaPods 0.29.0,布布扣,bubuko.com
The `master` repo requires CocoaPods 0.29.0
原文：http://www.cnblogs.com/so-magic/p/3580100.html