title: How to make system partition in AVD in emulator writable
body: <p>This is fairly a very old question but I am surprised that none of the solutions are working for me. I need to run an android app as system app in an AVD (in emulator) created for Android version 7.0. For this, I want to push apk file to system partition but I keep getting error saying it is read only file system. I found many similar questions on stackoverflow but nothing is working for me. I restarted adb in root, executed it with remount as suggested in answers to similar questions, but system partition file system permissions do not change. Here is a sample session:</p>
  
  <pre><code>mvsagar@mvslt:~/sw/android_sdk/platform-tools$ ./adb root
  restarting adbd as root
  mvsagar@mvslt:~/sw/android_sdk/platform-tools$ ./adb remount
  remount succeeded
  mvsagar@mvslt:~/sw/android_sdk/platform-tools$ ./adb push /home/mvsagar/projects/AndroidStudioProjects/LcnApps/app/LCNUE.apk  /system/app/LCNUE.apk
  adb: error: failed to copy '/home/mvsagar/projects/AndroidStudioProjects/LcnApps/app/LCNUE.apk' to '/system/app/LCNUE.apk': couldn't create file: Read-only file system
  </code></pre>
  
  <p>I have tried manually remounting with read/write(rw) options using adb shell, but the remounting fails.  </p>
  
  <p>Is there any way to have read/write permission on system partition?</p>
  
  <p>My dev env is Android Studio on Ubuntu.</p>