CocoaPods was not able to update the `master` repo. If this is an unexpected issue and persists you can inspect it running `pod repo update --verbose`
解决办法
先删除全局的缓存：
$ sudo rm -fr ~/Library/Caches/CocoaPods/
$ sudo rm -fr ~/.cocoapods/repos/master/
再执行：
$ sudo gem install cocoapods
$ pod setup
如果还是出现该问题则清空当前Pods目录然后再安装：
$ sudo rm -fr Pods/
[!] The `master` repo requires CocoaPods 1.0.0 - (currently using 0.39.0)
更新CocoaPods后问题解决
[!] /usr/bin/git clone https://github.com/CocoaPods/Specs.git master --depth=1
解决办法：执行 $sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer (-switch 后面加上你的Xcode.app包内容里的Developer的文件夹路径即可)
[!] /usr/bin/git clone https://github.com/CocoaPods/Specs.git master
Cloning into 'master'...
fatal: unable to access 'https://github.com/CocoaPods/Specs.git/': SSLRead() return error -9806
解决方法：clone Specs 到repos目录下面
$ cd ~/.cocoapods/repos
git clone https://github.com/CocoaPods/Specs.git
如果pod setup 依然失败，找到一个安装好了cocoapods的Mac电脑，在~/.cocoapods/repos目录下面拷贝出master文件到自己的Mac上的相应位置
ERROR: While executing gem ... (Errno::EPERM) Operation not permitted - /usr/bin/xcodeproj
$ sudo gem install cocoapods 时出现此问题
解决方法：sudo gem install -n /usr/local/bin cocoapods --pre
[!] /usr/bin/git clone https://github.com/CocoaPods/Specs.git master
Cloning into 'master'...
error: RPC failed; result=56, HTTP code = 200
fatal: The remote end hung up unexpectedly
fatal: early EOF
pod setup 时出现此问题；
解决方案一：
$ cd ~/.cocoapods/repo
$ git clone "https://github.com/CocoaPods/Specs"
解决方案二:
$ git config http.postBuffer 524288000
