我在9.2上更新了xcode，然后创建了一个项目并在其上安装了pod。 Pod已成功安装，但未创建白色文件.xcodeproj。然后我跑了sudo gem uninstall cocoapods，然后跑了sudo gem install cocoapods --pre。
它显示了此错误：
Could not find a valid gem 'cocoapods' (>= 0), here is why:
Unable to download data from https://rubygems.org/ - SSL_connect returned=1 errno=0 state=SSLv2/v3 read server hello A: tlsv1 alert protocol version (https://rubygems.org/specs.4.8.gz)