title: How to resolve flutter doctor issues with home brew?
body: <p>I am using OS X High Sierra.
  I started with the install documentation here:
  <a href="https://flutter.io/setup-macos/" rel="nofollow noreferrer">https://flutter.io/setup-macos/</a>
  however I cannot seem to install libimobiledevice and ideviceinstaller.</p>
  
  <p>When I start flutter doctor I get the following:</p>
  
  <pre><code>✗ libimobiledevice and ideviceinstaller are not installed. To install, run:
          brew install --HEAD libimobiledevice
          brew install ideviceinstaller
  </code></pre>
  
  <p>So I do as requested:</p>
  
  <pre><code>brew install --HEAD libimobiledevice
  Error: libimobiledevice 1.2.0_2 is already installed
  To install HEAD_2, first run `brew unlink libimobiledevice`
  
  
  brew install ideviceinstaller
  Warning: ideviceinstaller 1.1.0_4 is already installed
  </code></pre>
  
  <p>After that if I call the doctor again, the same error as above is displayed. How can I fix this?</p>