Dear all,

I have created a web interface that runs a perl script once the form has been submitted. The server is tomcat and the webpages are JSP.

I have written a little line in the beginning of the perl script that 'touches' a new file to indicate that it is running. Whilst running it, it puts its results into a previously created and unique directory.

This results are then in turn accessed again by the web interface.

Everything goes well except for one weird thing, when I want to run the script again, ie re-submit the form WITHIN the same session. The 'touched' file that indicates that the perl script was started is updated, so I KNOW that the perl script started to run. But there is NO OTHER output, and the script itself crashes or exits before I even can find it with 'ps ax'.

I am confused as to why it does this after the first time it is run. if I close the browser completely, and wait 60 minutes, then it will work again just fine.

I really believe it's something to do with the output streams: 

open SAVEERR, ">&STDERR";
open SAVEOUT, ">&STDOUT";
$|=1;
...rest of script...
close STDERR;
open STDERR, ">&main::SAVEERR";
close STDOUT;
open STDOUT, ">&main::SAVEOUT";

[download]
in the bean that runs the script I have this java code: 
String[] cmd ={"/home/seaver/MONSTER/monster", "-i" + jobID, filePath 
++ pdbFileName};
        try{
            Process proc = Runtime.getRuntime().exec(cmd);
            BufferedWriter output = new BufferedWriter(new OutputStrea
+mWriter(proc.getOutputStream()));
            BufferedReader input = new BufferedReader(new InputStreamR
+eader(proc.getInputStream()));
            BufferedReader error = new BufferedReader(new InputStreamR
+eader(proc.getErrorStream()));
            output.close();
            input.close();
            error.close();
        }catch (Throwable t){
            t.printStackTrace();
        }

[download]

can anyone throw any light on this?

thanks Sam

edit jeffa - s/pre/code/g

In reply to Perl script ran from Java Bean by seaver

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