title: Cannot install cocoa pods after uninstalling, results in error
body: <p>I removed cocoa pods because it claimed it had installed, but kept saying the command pod wasn't found afterward. When trying to reinstall cocoapods (<code>sudo gem install cocoa pods -v</code>) I get this error:</p>
  
  <blockquote>
    <p>ERROR:  While executing gem ... (Errno::EPERM)
        Operation not permitted - /usr/bin/pod</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/xDNoa.png"><img src="https://i.stack.imgur.com/xDNoa.png" alt="Screenshot for error"></a></p>
  
  <p>Any ideas?</p>