Android, Logcat and BufferedReader - no logs

Question

I'm making an application, which must show me in logs which applications I start on device. I use logcat ActivityManager:I *:S and it doing this well.. at some devices and emulators.

But at some devices it has strange behavior - everything I see in log is repetition of:

02-18 16:32:09.132: D/LockApp(4082): --------- beginning of /dev/log/main

Code snippet:

Process process = null;
try {
    process = Runtime.getRuntime().exec("logcat -c");
    process = null;
    process = Runtime.getRuntime().exec("logcat ActivityManager:I *:S");
    br = new BufferedReader(new InputStreamReader(process.getInputStream()));
    String line = null;

    line = br.readLine();

    while( line != null && !this.isInterrupted()){
        Log.d(Tag, "Start LockApp loop");
        Log.d(Tag, line);
    }
} catch (IOException e) {
    Log.d(Tag, e.toString());
}

And I have android.permission.READ_LOGS in Manifest

I`m doing it in Android 4.1 and 4.2

Answer 1

What is this logcat -c> this will Clears (flushes) the entire log and exits.

There are only V,D,I,W,E & WTF :-) Six type of logcat category

change it to Runtime.getRuntime().exec("logcat -e"); Link here:

EDIT: There is an problem in Reading in jelly bean link here

READ_LOGS permission on Jelly Beans (Android 4.1) will not be granted anymore to normal apps.

Apps are only allow to read their own logs.

See for more information

You could try to implement a function to grant yourself READ_LOGS permission with for users with rooted devices.