Error running exec(). Command: Working Directory: null Environment: null - how to execute a binary in Android correctly on a non-rooted device?

Question

I want to run an executable on a non-rooted android device.

Using the following commands in java

Runtime.getRuntime().exec("/bin/chmod 744 /data/data/com.example.myapp/myBin");
Runtime.getRuntime().exec("/data/data/com.example.myapp/myBin");

results in

Error running exec(). Command: [/data/data/com.example.myapp/myBin] 
    Working Directory: null Environment: null

I found alot of questions on this but no answer that worked in my case. How can I execute the binary file correctly?

When I see such a question, I normally think to poorly written code. Or to **malware**. — Phantômaxx, Feb 21 '15 at 13:59

score 3 · Accepted Answer · answered Mar 02 '15 at 12:04

3

If you are running this from a service (and not a app activity), you will have to set the permissions as 777.

answered Mar 02 '15 at 12:04

Shashank Singla

1,797
17
13

score 1 · Answer 2 · answered Feb 21 '15 at 17:48

Runtime.getRuntime().exec("/bin/chmod 744 /data/data/com.example.myapp/myBin");

While it may not be your only problem, on most builds of Android chmod lives in /system/bin and there is no /bin directory, so your failure is likely actually on the attempt to execute a non-existent tool, even before getting to your custom binary.

Error running exec(). Command: Working Directory: null Environment: null - how to execute a binary in Android correctly on a non-rooted device?

2 Answers2