Where can I find the description of the codes returned by exitValue()?

Question

Hi Everybody,
I have a java porgram on HP/UX and this program executes the OS level commands and exe file on HP UNIX. When I supply "/usr/bin ls -l" as a param to this program it executes it very well.
But if I pass the "/utils/Myapp/app arg1 arg2" as a parameter it returns some non zero codes
I tried several ways to make it work and I even harcoded the "/utils/Myapp/app arg1 arg2" in the program but it never executes it properly and I got the following return Code return by exitvalue() during my hit and trial method.
255,17,15,12
Does any one have clue what are they.
Note: When I executes /utils/Myapp/app arg1 arg2" from the UNIX prompt it works fine
The java program is given below.
Pl help
Thanks
Yatsomy.
This is my first program in JAVA.
import java.lang.Runtime;
import java.lang.Process;
import java.io.IOException;
import java.lang.InterruptedException;
class executecmd {
public static void main(String args[]) {
System.out.println("In main");
try {
/* Execute the command using the Runtime object and get the
Process which controls this command */
Process p = Runtime.getRuntime().exec(args[0]);
/* Use the following code to wait for the process to finish
and check the return code from the process */
try {
p.waitFor();
/* Handle exceptions for waitFor() */
} catch (InterruptedException intexc) {
System.out.println("Interrupted Exception on waitFor: " + intexc.getMessage());
System.out.println("Return code from process"+ p.exitValue());
System.out.println("Done executing");
/* Handle the exceptions for exec() */
} catch (IOException e) {
System.out.println("IO Exception from exec : " + e.getMessage());
e.printStackTrace();

Answer 1

1. exitValue() codes are the numeric codes returned by native applications you're calling: the meaning of this code is both application and platform dependant (it has nothing to do with java), so you should try to find those info in "app" documentation, or in HP Unix standard docs.
2. I think you'd better "debug" the Runtime.exec() behaviour by capturing stdout and especially stderr of the spawned process: doing so, you will be able to see error messages printed out by called applications or commands...
It's very simple using this small class:
/** connects I/O streams, just like a pipe :-)
* @author: Giorgio Maone
class Pipe {
private InputStream in;
private OutputStream out;
public Pipe(InputStream in, OutputStream out) {
   this.in=in; this.out=out;
public void connect() {
   new Thread() {
    public void run() {
     try {
      for(int b;(b=in.read())!=-1;) {
        out.write(b);
      out.flush();
    } catch(IOException ex) {}
  }.start();
}So you can do this:
Process p = Runtime.getRuntime().exec(args[0]);
new Pipe(p.getInputStream(),System.out).connect();
new Pipe(p.getErrorStream(),System.out).connect();
new Pipe(System.in,p.getOutputStream()).connect();
try {
System.out.println("Exit code: "+p.waitFor());
} catch(InterruptedException ex) {}If you want to use a "smart wrapper" on Runtime.exec(), feel free to use my MultiExec class:
/** executes multiple commands in one shell
* @author: Giorgio Maone
import java.io.*;
public class MultiExec {
static final boolean IS_WIN=System.getProperty("os.name").toLowerCase().indexOf("win")==0;
protected String shell=IS_WIN?"":"sh";
public void setShell(String s) {
   shell=s;
public String getShell() {
   return shell;
public Process exec(String cmds[]) throws IOException {
  File f=File.createTempFile("muexec",".bat");
  PrintWriter out=new PrintWriter(new FileWriter(f));
  if(IS_WIN) out.println("@echo off");
  for(int j=0,len=cmds.length; j<len; j++)
    out.println(cmds[j]);
  out.close();
  f.deleteOnExit();
  return Runtime.getRuntime().exec(shell+" "+f.getCanonicalPath());
public int execAndWait(String cmds[]) throws IOException {
   Process p=exec(cmds);
  new Pipe(p.getInputStream(),System.out).connect();
  new Pipe(p.getErrorStream(),System.out).connect();
  new Pipe(System.in,p.getOutputStream()).connect();
  int exitCode=-1;
  try {
   exitCode=p.waitFor();
   } catch(InterruptedException ex) {}
  return exitCode;
static class Pipe {
   private InputStream in;
  private OutputStream out;
  public Pipe(InputStream in, OutputStream out) {
    this.in=in; this.out=out;
  public void connect() {
    new Thread() {
     public void run() {
      try {
       for(int b;(b=in.read())!=-1;) {
         out.write(b);
       out.flush();
     } catch(IOException ex) {}
   }.start();