Question

My UI blocked only in 4.0.* by using clause:”Runtime.getRuntime().exec(“cat proc/meminfo”);”.
Is there something wrong in following code?
Thanks in advance.

Log:

03-27 13:37:18.545: I/MyActivity(19730): ini().429: 1332826638549
03-27 13:37:18.545: I/MyActivity(19730): ini().434: 1332826638549
03-27 13:37:18.865: D/dalvikvm(19611): GC_CONCURRENT freed 389K, 6% free 9733K/10311K, paused 1ms+2ms

Code:

Log.i(getClass().getName(), "ini().434: " + System.currentTimeMillis());

try {
    Process process = Runtime.getRuntime().exec("cat proc/meminfo");//! hang here       
    Log.i(getClass().getName(), "ini().436: " + System.currentTimeMillis());
    BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));                            
    Log.i(getClass().getName(), "ini().438: " + System.currentTimeMillis());
    String str = bufferedReader.readLine();
    totleMemory = Long.parseLong(str.replaceAll("\\s+", "").replaceAll("[a-zA-Z]", "").replaceAll(":", ""));                            
    Log.i(getClass().getName(), "ini().441: " + System.currentTimeMillis());
    totleMemory *= 1024;
    } catch (Exception e) {
    }   

Log.i(getClass().getName(), "ini().446: " + System.currentTimeMillis());

Answer 1

I just opened the terminal app on my phone which is running Android 4.0+ and ran your command “cat /proc/meminfo”. I did not allow the app to have “su” or “root” permissions, running as a normal app. The command completed successfully.

So if I can run it via command line using an application running on the phone, I am sure I can do via ADB shell and most likely in Java.

I’ve used this code in my applications before:

try 
    {
    Process process = Runtime.getRuntime().exec("/system/bin/cat /proc/meminfo");
    BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
    int read;
    char[] buffer = new char[4096];
    StringBuffer output = new StringBuffer();
    while ((read = reader.read(buffer)) > 0) 
    {
        output.append(buffer, 0, read);
    }
    reader.close();
    process.waitFor();

    // wrap this in a method and return the string
    return output.toString();
} catch (Exception e) {
}

However, when I have tried to run commands what I do not have the correct permissions to run, I have gotten that error “GC_CONCURRENT”.

Regards,