由于安装cocopds出现的错误

错误提示1

Error installing cocoapods:  activesupport requires Ruby version >= 2.2.2.

解决方案 ：

1、安装 RVM baby 版本管理器

$curl -L get.rvm.io | bash -s stable

//________等安装完成 出现下面这行提示以下___________

In case of problems: https://rvm.io/helpandhttps://twitter.com/rvm_io

执行

$source ~/.bashrc

$source ~/.bash_profile

测试是否安装正常

$rvm -v

//________提示以下___________

rvm 1.27.0 (latest) by Wayne E. Seguin, Michal Papis[https://rvm.io/]

2、用RVM升级Ruby查看当前ruby版本

$ruby -v

$rvm list known

//________提示以下___________

# MRI Rubies

[ruby-]1.8.6[-p420]

[ruby-]1.8.7[-head] # security released on head

[ruby-]1.9.1[-p431]

[ruby-]1.9.2[-p330]

[ruby-]1.9.3[-p551]

[ruby-]2.0.0[-p648]

[ruby-]2.1[.8]

[ruby-]2.2[.4]

[ruby-]2.3[.0]

[ruby-]2.2-headruby-head

# for forks use: rvm install ruby-head---url https://github.com/github/ruby.git --branch 2.2

# JRuby

安装ruby 2.2.2 执行

$rvm install 2.2.2

如果打印：

……  ruby-2.2.2 - #validate archive    ruby-2.2.2 - #extract    ruby-2.2.2 - #validate binary    ruby-2.2.2 - #setup    ruby-2.2.2 - #gemset created /Users/abc/.rvm/gems/ruby-2.2.2@global    ruby-2.2.2 - #importing gemset

/Users/abc/.rvm/gemsets/global.gems..............................    ruby-2.2.2 - #generating global wrappers........    ruby-2.2.2 - #gemset created /Users/abc/.rvm/gems/ruby-2.2.2    ruby-2.2.2 - #importing gemsetfile /Users/abc/.rvm/gemsets/default.gems

evaluated to empty gem list    ruby-2.2.2 - #generating default wrappers........    Updating certificates in '/etc/openssl/cert.pem'.    mkdir: /etc/openssl: Permission denied    mkdir -p "/etc/openssl" failed, retrying with sudo    LiuWenqiang password required for 'mkdir -p /etc/openssl':    and sudo mkdir worked

则说明安装成功了

打印代码：

Done with Command Line Tools (OS X 10.11) for Xcode

Done.

==> /usr/bin/sudo /bin/rm -f /tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress

==> Installing the Command Line Tools (expect a GUI popup):

==> /usr/bin/sudo /usr/bin/xcode-select --install

xcode-select: error: command line tools are already installed, use "Software Update" to install updates

Failed during: /usr/bin/sudo /usr/bin/xcode-select --install

Requirements installation failed with status: 1.