Cocoapos 报错 Generating Pods proj

cocoapos 执行 install  时  报错如下错误

Generating Pods project Abort trap: 6

需要执行如下命令

sudo gem uninstall cocoapods

sudo gem uninstall cocoapods-core

sudo gem uninstall cocoapods-deintegrate

sudo gem uninstall cocoapods-downloader

sudo gem uninstall cocoapods-plugins

sudo gem uninstall cocoapods-search

sudo gem uninstall cocoapods-stats

sudo gem uninstall cocoapods-try

sudo gem uninstall cocoapods-trunk

然后在执行 ：

sudo gem install cocoapods --pre

如果执行  sudo gem install cocoapods --pre 遇见

ERROR:  While executing gem ... (Gem::DependencyError)

    Unable to resolve dependencies: cocoapods requires molinillo 

需要：更新  gem 运行一下命令

sudo gem update --system

如果出现 错误：

ERROR:  While executing gem ... (Errno::EPERM)

    Operation not permitted - /usr/bin/xcodeproj

sudo gem install -n /usr/local/bin cocoapods --pre