Need help with Runtime.getRuntime().exec

Question

If there is a better place to post please let me know. I need some help understanding what is going on and was hoping someone might be able to provide some information. I would like to use Runtime.getRuntime().exec to copy a file in linux. Here is the code I am using:
try {
Process p = Runtime.getRuntime().exec("cp -v foo foo2");
BufferedReader in = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = null;
while ((line = in.readLine()) != null) {
System.out.println(line);
} catch (IOException e) {
e.printStackTrace();
If I use cp, with the System.out.println(line) I can see that it has copied and of course when I check the command line indeed it has. My problem is that I really need to use the dd command, but I can't see the output that dd displays. It copies the file just fine but I need the output. If someone can provide some explaination or help I would really appreciate it. Thanks.

Answer 1

By default, dd sends its output to stdout, so any status messages it has go to stderr. Use getErrorStream (double check the docs for the method name) just like you're currently using getInputSTream.