import java.io.*;

public class Program01 {

    public static void main(String args[]) {
        String s = null;

        try {

            Process p = Runtime.getRuntime().exec("ls");

            BufferedReader stdInput = new BufferedReader(new
                    InputStreamReader(p.getInputStream()));

            BufferedReader stdError = new BufferedReader(new
                    InputStreamReader(p.getErrorStream()));

            // kimenet olvasása:
            System.out.println("A alapértelmezett kimenet:\n");
            while ((s = stdInput.readLine()) != null) {
                System.out.println(s);
            }

            // hibakimenet olvasása:
            System.out.println("Az alapértelmezett kimenet:\n");
            while ((s = stdError.readLine()) != null) {
                System.out.println(s);
            }

            System.exit(0);
        }catch (IOException e){
            System.out.println("Hiba történt - Oka: ");
            e.printStackTrace();
            System.exit(-1);
        }
    }
}