Running commands from the Command Prompt - Runtime.getRuntime().exec()

Question

Hi there,
I'm already able to run several commands in the command prompt.
But my problem is that I need all the commands that I run share the same context.
If, for example, I run "cmd /c set HOME=C:" (1st command), I want to be able to access that variable the next time, so that later when I run "dir %home%" it shows the directories in c: (This is just a example this is not what I really want to do...)
I used code posted in a newsgroup (don't remember which)
This is the code I use to execute commands:
     private int execute(String command)
     int exitVal = 0;
try
String nomeOS = System.getProperty("os.name" );
String[] cmd = new String[3];
if( nomeOS.equals( "Windows NT" ) || nomeOS.equals("Windows 2000") )
cmd[0]="cmd.exe";
cmd[1]="/c";
cmd[2]=command;
else if( nomeOS.equals( "Windows 95" ) )
cmd[0]="command.com";
cmd[1]="/c";
cmd[2]=command;
if (rt==null)
     rt = Runtime.getRuntime();
          Process proc = rt.exec(cmd);
          CommandStream erro = null;
          // erros?
          if (proc.getErrorStream()!=null)
               erro = new CommandStream(proc.getErrorStream());
               erro.start();
// output?
CommandStream output = new
CommandStream(proc.getInputStream());
// arranque
output.start();
// erros???
exitVal = proc.waitFor();
     } catch (IOException e)
               System.out.println("Exce !!!" );
               e.printStackTrace();
     catch (InterruptedException ie)
               System.out.println("Ocorreu uma excep��o !!!" );
               ie.printStackTrace();
return exitVal;      

Answer 1

My problem is bigger than setting a few parameters,
I'm doing a GUI to a CVS client and the problem is that some commands of CVS only work if you're in the right directory, or if you're authenticated, and all of this is easily done doing a series of execution:
In a command prompt opened I would:
set cvsroot=:pserver:lpinho@w2palf38:/project
cvs -d :pserver:lpinho:xxxxx@w2palf38:/project login
mkdir temp_my_proj
cd temp_my_proj
cvs checkout my_projectAll this would make what I wanted...
And there's another thing, when I set the envp, I get some errors like "cvs.exe is not recognized as an internal or external command" (the path went bye bye) and if I set the path (envp[0]="path=c:\cvsnt"), I'm able to run cvs but I get a crazy error "No such host is known" (I run exactly the same command in the command prompt and it works...)
Do you know any way of getting the current environment, and pass it as the envp parameter?
Thank You
Luis Pinho