Running Shell commands though java code on Android?

Question

I've got an app that's supposed to use some shell commands to copy a file from the sdcard to /system/media/. It will require root, and I am testing on a rooted device. I'm using runtimes to execute the shell commands, but it's not working. Here's what I've got for my runtimes

public void RunAsRoot{String[] commands = {"sysrw", "rm /data/local/bootanimation.zip", "sysro"};{
    Process p = Runtime.getRuntime().exec("su");
    DataOutputStream os = new DataOutputStream(p.getOutputStream());            
    for (String tmpCmd : commands) {
    os.writeBytes(tmpCmd+"\n");
    }           
    os.writeBytes("exit\n");  
    os.flush();
}

But my logcat only shows two of them not getting rejected

07-30 03:14:11.112: WARN/su(3593): request rejected (10047->0 /system/bin/sh)
07-30 03:14:11.132: DEBUG/su(3592): 10047 com.bba.stormdroid executing 0 /system/bin/sh using shell /system/bin/sh : sh
07-30 03:14:11.152: WARN/su(3594): request rejected (0->0 /system/bin/sh)
07-30 03:14:11.182: WARN/su(3595): request rejected (0->0 /system/bin/sh)
07-30 03:14:11.202: WARN/su(3596): request rejected (0->0 /system/bin/sh)
07-30 03:14:11.242: DEBUG/su(3597): 10047 com.bba.stormdroid executing 0 /system/bin/sh using shell /system/bin/sh : sh

Those two look to be the sysrw and sysro commands, yet the app still asks for root permission when I trigger this code. I'm new to working with root stuff and I can't seem to figure out how to get this to work.

This isn't working for me and I'm not getting any FileNotFound exceptions or anything in Java. Also, SuperSU intercepts the root request and I'm able to grant it so I know that `getRuntime()` is working. For some reason it just won't let me manipulate files in the `/system/media` folder. — fIwJlxSzApHEZIl, Mar 14 '13 at 00:24
Sorry for the naive question: this only works with a rooted device, isn't it? — Diana, Oct 24 '13 at 10:09

user496854 · Accepted Answer · 2011-07-31T21:46:20.787

28

To run root commands, you have to use the flllowing format:

    public void RunAsRoot(String[] cmds){
            Process p = Runtime.getRuntime().exec("su");
            DataOutputStream os = new DataOutputStream(p.getOutputStream());            
            for (String tmpCmd : cmds) {
                    os.writeBytes(tmpCmd+"\n");
            }           
            os.writeBytes("exit\n");  
            os.flush();
}

where you pass in an array of strings, each string being a command that needs to be executed. For example:

String[] commands = {"sysrw", "rm /data/local/bootanimation.zip", "sysro"};

edited Jul 31 '11 at 21:46

answered Jul 30 '11 at 09:32

user496854

6,461
10
47
84

When I put that in my onClick, it says the ()'s around (String[] cmds) should be ;'s, which just adds more errors when I do that. – Ben Jul 31 '11 at 04:26
I just edited my original answer to show an example of the string array that needs to be passed in – user496854 Jul 31 '11 at 21:48
Unless I'm doing this wrong, it's highlighting RunAsRoot and saying void is an invalid type for RunAsRoot. I've updated my question with the code I have now – Ben Aug 01 '11 at 01:12
You can't pass in a string array like that. You have to assign it first, then pass it in as a variable. The RunAsRoot function should be identical to what I posted – user496854 Aug 02 '11 at 09:05
3

One thing I wonder is why input is via `outputstream` and output via `inputstream`, naming issue ? – S.D. Apr 29 '13 at 06:18
3

Is it possible to get the output of the command I just executed..? for example "ls /data" – 3lokh May 26 '15 at 17:14
1

The above code seems not working with non-Rooted devices – vgokul129 Jan 03 '17 at 14:22

Running Shell commands though java code on Android?

1 Answers1

Linked