转自:http://blog.csdn.net/xingxingrainlove/article/details/53257944
今天在运行项目时突然遇到异常报错：not find -lpod；一开始感觉很莫名其妙，随后意识到可能是cocoaPods的问题，于是尝试更新pod install，结果红色警告提示：
The `master` repo requires CocoaPods 1.0.0 - (currently using 0.39.0)；所以最终问题是cocoaPods版本太低，需要更新了（我的当前版本是0.39.0）。
《自以为是的更新步骤：
1.更新gem
$ sudo gem update
结果如下：
Updating installed gems
Updating CFPropertyList
Fetching: CFPropertyList-2.3.3.gem (100%)
Successfully installed CFPropertyList-2.3.3
Parsing documentation for CFPropertyList-2.3.3
Installing ri documentation for CFPropertyList-2.3.3
Installing darkfish documentation for CFPropertyList-2.3.3
Parsing documentation for CFPropertyList-2.3.3
Updating activesupport
Fetching: concurrent-ruby-1.0.2.gem (100%)
Successfully installed concurrent-ruby-1.0.2
Fetching: activesupport-5.0.0.1.gem (100%)
ERROR: Error installing activesupport:
activesupport requires Ruby version >= 2.2.2.//Ruby version的版本较低， 最低需要2.2.2版本
Updating bigdecimal
Fetching: bigdecimal-1.2.7.gem (100%)
Building native extensions. This could take a while...
Successfully installed bigdecimal-1.2.7
Parsing documentation for bigdecimal-1.2.7
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for /Library/Ruby/Gems/2.0.0/extensions/universal-darwin-15/2.0.0/bigdecimal-1.2.7/bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.o, skipping
Installing ri documentation for bigdecimal-1.2.7
Installing darkfish documentation for bigdecimal-1.2.7
Parsing documentation for bigdecimal-1.2.7
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for /Library/Ruby/Gems/2.0.0/extensions/universal-darwin-15/2.0.0/bigdecimal-1.2.7/bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.o, skipping
Updating claide
Fetching: claide-1.0.1.gem (100%)
Successfully installed claide-1.0.1
Installing darkfish documentation for CFPropertyList-2.3.3
Parsing documentation for CFPropertyList-2.3.3
Updating activesupport
Fetching: concurrent-ruby-1.0.2.gem (100%)
Successfully installed concurrent-ruby-1.0.2
Fetching: activesupport-5.0.0.1.gem (100%)
ERROR: Error installing activesupport:
activesupport requires Ruby version >= 2.2.2.//Ruby version的版本较低， 最低需要2.2.2版本
Updating bigdecimal
Fetching: bigdecimal-1.2.7.gem (100%)
Building native extensions. This could take a while...
Successfully installed bigdecimal-1.2.7
Parsing documentation for bigdecimal-1.2.7
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for /Library/Ruby/Gems/2.0.0/extensions/universal-darwin-15/2.0.0/bigdecimal-1.2.7/bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.o, skipping
Installing ri documentation for bigdecimal-1.2.7
Installing darkfish documentation for bigdecimal-1.2.7
Parsing documentation for bigdecimal-1.2.7
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for /Library/Ruby/Gems/2.0.0/extensions/universal-darwin-15/2.0.0/bigdecimal-1.2.7/bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.bundle, skipping
unable to convert "\xCA" from ASCII-8BIT to UTF-8 for bigdecimal.o, skipping
Updating claide
Fetching: claide-1.0.1.gem (100%)
……………...
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/xcodeproj//意思是gem更新失败了，出现了错误，究其原因就是Ruby version的版本较低导致。
注：这种情况是不正常的，说明更新失败，其它可以忽略：失败原因就在画线的两行ERROR里面。
2.我自动忽略了以上报错继续进行下面的操作：
gem sources -l
sudo gem install cocoapods
很显然注定是要失败的，一直报错：
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/xcodeproj
最后一步pod setup
继续报错：[!] The `master` repo requires CocoaPods 1.0.0 - (currently using 0.39.0)
所以什么用也没有！！！！！
《正确的解决步骤
从网上搜索解决方案，经过实践总结正确的步骤。（帮助文章链接：http://blog.csdn.net/yangyangzhang1990/article/details/52252146）
很明显从上面的问题中找到了最根本的原因是Ruby的版本较低。
第一步：首先检测各种版本是否合格：
rvm-v :ram相当于一个ruby仓库，管理ruby不同版本。（我的当前版本是1.26.11，可以，当然最好更新到1.27.0）
如果低于1.26.11需要安装一下：source ~/.rvm/scripts/rvm
安装成功提示是：rvm 1.27.0 (latest) by Wayne E. Seguin
版本为：1.27.0
第二步：将Ruby的版本升级到2.2.2，（建议不要安装 最新版的 2.3.0）
rvm install ruby 2.2.2
安装成功提示是：ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin14]
我的提示是：Warning, new version of rvm available '1.27.0', you are using older version '1.26.11'.j警告版本低于最新版，暂时不影响。
ruby -v:看一下当前版本
安装成功提示是：ruby 2.2.2p95 (2015-04-13 revision 50295) [x86_64-darwin15]
如果还没有安装成功，提示你 home－brew 没有安装，那你需要安装home－brew
第三步：安装home-brew
/usr/bin/ruby -e "$(curl -fsSLhttps://raw.githubusercontent.com/Homebrew/install/master/install)"
详细安装 步骤 可查看博客地址：http://blog.csdn.net/yangyangzhang1990/article/details/51578565
第四步：安装cocoaPods
安装home－brew 成功后，执行 brew install ruby 2.2.2 。
首先 ruby －v 查看你的ruby 版本
接着 rvm －v 查看你的rvm 版本
接着gem－v查看你的gem版本
接着 brew －v 查看你的brew 版本
gem source－l查看你的镜像源。这里推荐使用 腾讯云 镜像。
gem sources --remove老得镜像源地址
gem sources -a新的镜像源地址
gem sources -l查看当前最新的镜像源地址
具体操作提示：
czhdeiMac:kuihuajingyingwang czh$gem sources -l
*** CURRENT SOURCES ***
https://ruby.taobao.org
https://ruby.taobao.org/
czhdeiMac:kuihuajingyingwang czh$gem sources --removehttps://ruby.taobao.org
https://ruby.taobao.orgremoved from sources
czhdeiMac:kuihuajingyingwang czh$gem sources -ahttp://gems.ruby-china.org/
http://gems.ruby-china.org/added to sources
czhdeiMac:kuihuajingyingwang czh$sudo gem install -n /usr/local/bin cocoa pods //这个地方不能用之前旧的更新方法：sudo gem install cocoapods
Password:
Fetching: i18n-0.7.0.gem (100%)
Successfully installed i18n-0.7.0
如果这样执行 pod install的时候还出现
The dependency ``isnotusedinany concrete target
The dependency `AFNetworking`isnotusedinany concrete target
官网是这样给推荐的：
在创建Podfile的时候，用这种格式使用，
platform:ios,'8.0'
#use_frameworks!个别需要用到它，比如reactiveCocoa
target 'MyApp' do
pod'AFNetworking','~> 2.6'
pod'ORStackView','~> 3.0'
pod'SwiftyJSON','~> 2.3'
end
里面的MyApp记得替换为自己攻城里面的target。这样就基本OK了，执行pod install / pod update 就都可以了。（use_frameworks! 这个是个别需要的，这里修改一下，可以把我上面的代码中的这一行【删除】）
Successfully installed claide-1.0.1
[!] Pods written in Swift can only be integrated as frameworks; add `use_frameworks!` to your Podfile
正确的写法Swift：
platform :ios, ‘8.0’
target ‘TestObjectTwo’do
pod ‘Alamofire’, ‘~>4.0’
pod ‘SnapKit’, ‘~>3.0.2’
use_frameworks!
end
在安装CocoaPods出现了以下问题:
ERROR: SSL verification error at depth 1: unable to get local issuer certificate (20)
ERROR: You must add /C=IL/O=StartCom Ltd./OU=Secure Digital Certificate Signing/CN=StartCom Certification Authority to your local trusted store
ERROR: SSL verification error at depth 2: self signed certificate in certificate chain (19)
ERROR: Root certificate is not trusted (/C=US/O=GeoTrust Inc./CN=GeoTrust Global CA)
出现这个问题的原因主要是Ruby环境需要2.2版本以上，所以要更新Ruby环境。
更新Ruby环境
0.首先要安装 Homebrew 终端输入这条命令即可 /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
1.安装rvm $ curl -L get.rvm.io | bash -s stable
2.装载rvm $ source ~/.rvm/scripts/rvm
3.安装2.3.0版本ruby $ rvm install 2.3.0
4.将2.3.0设为默认 $ rvm use 2.3.0 --default