title: screenrecord not working in emulator
body: <p>Since 4.4 KitKat, Android has a shell utility screenrecord to record the Android device screen. </p>
  
  <p>If I connect a physical device with the adb utility over USB, I can do the following:</p>
  
  <pre><code>adb shell screenrecord /sdcard/sample.mp4
  adb pull /sdcard/sample.mp4
  </code></pre>
  
  <p>But if I do the above for an Android emulator, I will get an empty sample.mp4 file.</p>
  
  <pre><code>adb shell screenrecord /sdcard/sample.mp4
  adb shell ls -l /sdcard/sample.mp4
  -rw-rw---- root     sdcard_r        0 2016-06-18 05:37 sample.mp4
  </code></pre>
  
  <p>If I execute screenrecord directly in a root console in emulator, I see the following:</p>
  
  <pre><code>root@flo:/system/bin # ./screenrecord /sdcard/sample.mp4                       
  [1] + Stopped (signal)     ./screenrecord /sdcard/sample.mp4 
  root@flo:/system/bin # 
  [1] + Illegal instruction  ./screenrecord /sdcard/sample.mp4 
  </code></pre>
  
  <p>Why does screenrecord not work for emulator?</p>