cocoapods更新某个版本

看看cocoapod版本号

$pod --version

Ignoring ffi-1.9.23 because its extensions are not built.  Try: gem pristine ffi --version 1.9.23
1.6.1

1.6.1是我的版本号，改成你目前的，卸载老版本

$sudo gem uninstall cocoapods -v 1.6.1
Password:需要输入密码
Successfully uninstalled cocoapods-1.6.1

$sudo gem uninstall cocoapods-core -v 1.6.1
Successfully uninstalled cocoapods-core-1.6.1

安装1.6.0版本

$sudo gem install cocoapods -v 1.6.0

如果报错

ERROR:  While executing gem ... (Gem::FilePermissionError)
    You don't have write permissions for the /usr/bin directory.

使用如下

$sudo gem install cocoapods -v 1.6.0 -n /usr/local/bin
Fetching: cocoapods-core-1.6.0.gem (100%)
Successfully installed cocoapods-core-1.6.0
Fetching: cocoapods-1.6.0.gem (100%)
Successfully installed cocoapods-1.6.0
Parsing documentation for cocoapods-core-1.6.0
Installing ri documentation for cocoapods-core-1.6.0
Parsing documentation for cocoapods-1.6.0
Installing ri documentation for cocoapods-1.6.0
Done installing documentation for cocoapods-core, cocoapods after 6 seconds
2 gems installed

卸载全部cocoapods

sudo gem uninstall cocoapods

安装

sudo gem install -n /usr/local/bin cocoapods -v 1.6.0