title: Ninja command not found in terminal
body: <p>-bash: ninja: command not found not found error in terminal. I am building webrtc for iOS and therefore I am following <a href="https://webrtc.org/native-code/ios/" rel="nofollow">WebRTC Guide</a> when I run below command in terminal it says <code>-bash: ninja: command not found</code>, am I missing anything? I have followed guide.</p>
  
  <pre><code>    ninja -C out_ios/Debug-iphoneos AppRTCDemo
      ninja -C out_ios/Release-iphoneos AppRTCDemo
      ninja -C out_sim/Debug-iphonesimulator AppRTCDemo
  </code></pre>