I need root permissions to execute a native application under Android?

Question

I have compiled a native application, a terminal only application basically, with the android NDK, my main problem right is that I can't change the permissions on my executable ( a dynamically linked one ) like so chmod +x executable to test and use the application.

I need to root my device just to do that ?

I tried with both adb shell and a random terminal application directly from my phone.

score 2 · Answer 1 · edited May 23 '17 at 12:06

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These guys say root is needed: How to compile C into an executable binary file and run it in Android from Android Shell?

From my understanding, the regular sdcard is mounted with no execution permission, so you need to write to something like /data/local/, which indeed requires root access.

edited May 23 '17 at 12:06

Community

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answered Jul 27 '13 at 03:02

Damian

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score 2 · Accepted Answer · edited May 23 '17 at 12:20

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No, you don't need to root a device to use executable binaries. You cannot put it on /sdcard but on most devices there is a directory /data/tmp or /data/local/tmp where you can push files with adb and execute with adb shell.

The robust option is to package an executable in an APK and get it on device by installing the APK, see Is it possible to run a native arm binary on a non-rooted android phone? or How to package native commandline application in apk?.

Note that you cannot change the LD_LIBRARY_PATH, so be careful if your executable depends on some shared libs that are not part of /system/lib.

edited May 23 '17 at 12:20

Community

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answered Jul 27 '13 at 10:18

Alex Cohn

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and I suppose that there is no such thing as an `ldd`-like utility ... ? – user2485710 Jul 27 '13 at 10:20
You can run ldd on your PC – Alex Cohn Jul 27 '13 at 10:25
See also https://groups.google.com/forum/m/#!topic/android-developers/xYFvnBDfGu8 – Alex Cohn Jul 27 '13 at 10:28
Note that in the brand new NDK r9 there is a special tool for you: see [NDK-DEPENDS.html](https://android.googlesource.com/platform/ndk/+/master/docs/text/NDK-DEPENDS.text) – Alex Cohn Jul 28 '13 at 13:09
Update: after Android 4.4 (and higher), native program executable will need root access and need to be run on /data/local/tmp – dns May 04 '18 at 05:44
@dns please explain. I still can run executables installed to `ApplicationInfo.nativeLibraryDir` even on 8.1, without root – Alex Cohn May 04 '18 at 07:14
I can't run it without root on my phone (Haier) & tablet (Samsung Galaxy Tab) running android 5 & 6. Exactly like @3c71 answer. – dns May 04 '18 at 07:47
@dns That was about data directory, not libs – Alex Cohn May 04 '18 at 09:58

score 1 · Answer 3 · answered Mar 08 '15 at 13:31

If you don't package your native code as an Android app, you'll need to run it from shell.

Starting with Android KitKat/Lollipop, executables can only be run from restricted locations. eg an executable installed in /data/data//... will not be allowed to run in any ways, be it with or without root.

Before KitKat, one can copy the executable to its own data directory, make it executable and run it. Not anymore in more recent version of KitKat.

So you will definitively need root to run linux exe on recent versions of Android.

I need root permissions to execute a native application under Android?

3 Answers3