Copy files to root Partition programatically

Question

I am developing a root app for modifying build.prop programatically. I copied build.prop from /system/build.prop to /sdcard/ but after modifying it I was unable to copy back to root partition

here is my code for copying build.prop from /system/build.prop to /sdcard/

protected void SUCommand()
{
    String sSUCommand = "cp /system/build.prop /sdcard/";
    final String[] sCommand = {"su","-c",sSUCommand};

    Thread thSUProcess = new Thread()
    {
        public void run()
        {
            try
            {
                Process p = Runtime.getRuntime().exec(sCommand);

            }
            catch(Exception e){}
        }

    };


    thSUProcess.start();

}

I changed String sSUCommand = "cp /system/build.prop /sdcard/"; to String sSUCommand = "cp /sdcard/build.prop /system/"; to copy it to system partition but didn't worked

I already rooted my phone and running lot of root apps successfully please tell me the right way to do it

Answer 1

You might want to mount system partition as rw instead of rd so as to do it

https://android.stackexchange.com/questions/25250/how-to-mount-system-in-rw-mode-if-no-custom-recovery