使用pod install安裝第三方插件時，可能會出現如下異常：
Installing SDWebImage (3.7.3)
[!] Error installing SDWebImage
[!] /usr/bin/git clone https://github.com/rs/SDWebImage.git /var/folders/n2/hd05fc151kbb41qjbrrrbx2c0000gn/T/d20151109-4159-e0n2lh --single-branch --depth 1 --branch 3.7.3
Cloning into '/var/folders/n2/hd05fc151kbb41qjbrrrbx2c0000gn/T/d20151109-4159-e0n2lh'...
error: RPC failed; result=18, HTTP code = 200
fatal: The remote end hung up unexpectedly
fatal: early EOF
fatal: unpack-objects failed
此時，解決方法是，在終端運行如下語句
[objc] view plain copy
sudo gem install cocoapods
待運行完成后，在終端再次執行命令
[objc] view plain copy
pod install