Cocoapos 报错信息 Generating Pods project Abort trap: 6

cocoapos 执行 pod install 时 报错如下错误

Generating Pods project
 Abort trap: 6

需要逐步执行下面的命令

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

最后在执行就可以了

sudo gem install cocoapods --pre

如果出现下面的错误信息，只要执行对应的命令就可以了，最后再重新执行上面那一行命令
-----------------------------我是分割线-------------------------------------
问题一：

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

问题二：

ERROR:  While executing gem ... (Errno::EPERM)
    Operation not permitted - /usr/bin/xcodeproj

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

问题三：

ERROR:  While executing gem ... (Errno::EPERM) 
Operation not permitted - /usr/bin/pod

可以参考这篇文章 http://blog.csdn.net/andanlan/article/details/50061775
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