Using runtime.exec,process streams

Hi all,
I am using runtime.exec to execute a batch file(rmdir /s/q directoryname) which deletes all the files in a certain directory(including subdirectories). However, some of the files are not deleted since they are being used by other processes.
I have closed all file references but still the batch file says they are being used by other processes. The File.canWrite() method however, returns true for all the files. I have also tried to delete the files using file.delete but it does not work.
So I have 2 questions.
1. Can I forcibly delete these files some other way.
2. If i call a batch file to delete the files and it fails on some files, the command window displays "cannot delete files". How can I write out thse messages into a text file which i can use as a log file.Do I have to use Process.getInputstream()/Process.getInputstream() ? If so, how?
Thanks for your help.
Vinny

I tried the following before but the string i get is always empty, but i can see there are messages in the command window. Please let me now if i am doing something wrong.
try{
Process p = rt.exec("cmd.exe /c start deletefiles.bat");
InputStream ins = p.getInputStream();
byte[] bytearray = new byte[1024];
int bytecount;
String dos_string="";
BufferedInputStream bis = new BufferedInputStream(ins);
while ((bytecount = bis.read(bytearray, 0, 1024)) > -1) {
String str = new String(bytearray,0,bytecount);
dos_string += str;
System.out.println("dos string is" +dos_string);
catch (Exception e) {
System.out.println("Error: " + e);

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    java.io.IOException: java.io.IOException: "/home/vilas/Documents/Project/build/CLISP/linux/lisp.run": not found
            at java.lang.UNIXProcess.<init>(UNIXProcess.java:143)
            at java.lang.Runtime.execInternal(Native Method)
            at java.lang.Runtime.exec(Runtime.java:566)
            at java.lang.Runtime.exec(Runtime.java:428)
            at jplan.communication.lispserver.LispServer.startupServer(LispServer.java:143)
            at jplan.communication.lispserver.LispServer.run(LispServer.java:109)
            at java.lang.Thread.run(Thread.java:534)lisp.run has all the necessary permissions. If I copy the string (/home/vilas/Documents/Project/build/CLISP/linux/lisp.run) and paste it in a terminal and press enter, the application starts up fine without any problems!! Can you please tell me what could be going wrong?
    The following extra information maybe helpfull:
    1) I use the exec(String command, String[] envp, File dir) version of exec.
    2) The complete format of the command is as follows (one long string):
    "/home/vilas/Documents/Project/build/CLISP/linux/lisp.run" -B "/home/vilas/Documents/Project/build/CLISP/linux" -M "/home/vilas/Documents/Project/build/CLISP/linux/lispinit.mem" -i loader.lisp
    Thanks in advance for your time and efforts.

    I found the problem after extensively searing the forums (looking upto page 4 !! of the results). The problem was that I was using quotes to surround the paths in the command. If you copy and paste it in a terminal it will work fine but it does not work with runtime.exec. I am not sure, but I think the reason is that when a terminal is used, some pre-processing of the commands take place before they are passed onto the OS(shell). But while using runtime.exec, that pre-processing is not peformed and therefore some things will not work.
    In order to fix the problem, I use quotes only when the OS is windows. In other cases(OS X, Linux) I escape the spaces i.e. replace " " with "\ ".
    PS: The executable is a binary compiled from C code.

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