Question

I just want to execute my file from a specific folder. in my case /data/data/my-package/files/.
So i tried :

 Process process2=Runtime.getRuntime().exec("cd /data/data/my-package/files/");
 process2.waitFor();
 process2=Runtime.getRuntime().exec("./myfile");

It doesn’t work. could anyone tell me please the right way to do that . Thanks

Answer 1

It should be possible to call the executable with a specific working directory using Runtime.exec(String command, String[] envp, File dir)

as follows:

Process process2=Runtime.getRuntime().exec("/data/data/my-package/files/myfile",
        null, new File("/data/data/my-package/files"));

maybe without the full path to myfile

Process process2=Runtime.getRuntime().exec("myfile",
        null, new File("/data/data/my-package/files"));

Context#getFilesDir() instead of hardcoding the path should work too and is safer / cleaner than specifying the path yourself since it is not guaranteed that /data/data/..
is always the correct path for all devices.

Process process2=Runtime.getRuntime().exec("myfile",
        null, getFilesDir()));

The problem with cd somewhere is that the directory is changed for a different Process so the second call to exec in a new Process does not see the change.