Question

how do you execute gdb commands using process object in java?

charmae@charmae-pc:~/Desktop$ gcc -g file.c
charmae@charmae-pc:~/Desktop$ gdb ./a.out
GNU gdb (Ubuntu/Linaro 7.3-0ubuntu2) 7.3-2011.08
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
For bug reporting instructions, please see:
<http://bugs.launchpad.net/gdb-linaro/>...
Reading symbols from /home/charmae/Desktop/a.out...done.
(gdb) run
Starting program: /home/charmae/Desktop/a.out 
address of x = 0xbffff2f8
address of y= 0xbffff2fc
address of x = 0xbffff2f8
value of x = 1
[Inferior 1 (process 4268) exited with code 017]
(gdb) 

In my java code:

 Runtime rt = Runtime.getRuntime();
 Process proc = rt.exec("gdb ./a.out");
                rt.exec("run");
 BufferedReader std = new BufferedReader(new 
                     InputStreamReader(proc.getErrorStream()));
 while ((s = std.readLine()) != null) {
                 System.out.println(s);
               }

Answer 1

Yey! Answered my own question.. i used pipe processing.

    public class GDBpipeWriter extends Thread{

        public void run(){
        Process p = null;
        try {
        p = Runtime.getRuntime().exec("gdb a.out --interpreter=console");
       new Thread(new SyncPipe(p.getErrorStream(), System.err)).start();
       new Thread(new SyncPipe(p.getInputStream(), System.out)).start();
        PrintWriter stdin = new PrintWriter(p.getOutputStream());

        stdin.flush();
        stdin.println("break 4");
        stdin.flush();
        stdin.println("break 10");
        stdin.flush();
        stdin.println("run");
        stdin.flush();

        /// write any other commands you want here
       // stdin.close();


        } catch (Exception e) {
            e.printStackTrace();
        }
        }
    }


class SyncPipe implements Runnable
{
public SyncPipe(InputStream istrm, OutputStream ostrm) {
      istrm_ = istrm;
      ostrm_ = ostrm;
  }
  public void run() {
      try
      {
          final byte[] buffer = new byte[1024];
          for (int length = 0; (length = istrm_.read(buffer)) != -1; )
          {
              ostrm_.write(buffer, 0, length);
          }

      }
      catch (Exception e)
      {
          e.printStackTrace();
      }
  }
  private final OutputStream ostrm_;
  private final InputStream istrm_;
}