Permission denied while writing a systemfile on android

0
votes

I was trying to write to /sys/class/switch/hdmi/state but i got permission denied error.

# echo 0 > /sys/class/switch/hdmi/state                                 
/system/bin/sh: can't create /sys/class/switch/hdmi/state: Permission denied

I searched online and found the below answer.

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

My question is, where do i set this permission? If android_manifest.xml, then which one? there are a lot of android_manifest files.

androidandroid-permissionsandroid-sourcehdmiruntime-permissions
To your main app manifest not to any library if you are using. One more thing one app have only one manifest file until unless you use any library – Aadesh Mishra
@AadeshMishra: But I'm not using any app. I just wanted to see if my HDMI will get turned off if i gave /sys/class/switch/hdmi/state 0. – Sourabrt
If you use adb shell to execute this command, maybe you should execute adb root before you enter adb shell to execute the above command. – utzcoz