Re: Suspended processes

I knew it was something like that!

I just had a look at the NIO classes, and to be honest, i dont see where
they fit in, it would be great to simply have non-blocking IO, but does
anyone have an example of how I can have a non-blocking read of output and
stderr?

Thanks
Sam




>    I'm not sure but it I would guess at one of two issues:
>
>   1. You don't seem to be reading the output and stderr in the
>      fragment.  You need to keep these channels moving, otherwise the
>      process will hang trying to deliver output.  You could consider
>      setting the IO to /dev/null (or NUL:) in the script so as to
>      assure there is no output pending.
>   2. If you do start reading from these, keep in mind that the
>      container is usually in charge of managing threads.  Since most
>      examples show creating threads to read and process the output,
>      this may be a problem.  This is because the default read/write
>      facilities don't support non-blocking IO, you need to use the NIO
>      classes for that.
>
>
>
>Sam Seaver wrote:
>
>>I have a JSP web interface that runs a perl script natively using a bean:
>>
>>String[] cmd ={"/home/seaver/MONSTER/monster", "-i" + getJobID(),
>>filePath +
>>dir + getPdbFileName()};
>>        try{
>>            Process proc = Runtime.getRuntime().exec(cmd);
>>            BufferedWriter output = new BufferedWriter(new
>>OutputStreamWriter(proc.getOutputStream()));
>>            BufferedReader input = new BufferedReader(new
>>InputStreamReader(proc.getInputStream()));
>>            BufferedReader error = new BufferedReader(new
>>InputStreamReader(proc.getErrorStream()));
>>        }catch (Throwable t){
>>            t.printStackTrace();
>>        }
>>
>>The program perl script, monster, runs fine natively, and it runs fine
>>when
>>activated from the web interface.
>>
>>The files passed into the web interface contains records which monster
>>parses and then inputs into a small C program.  This all works fine, even
>>with multiple records (leading to the one monster instance running the C
>>program multiple times)
>>
>>however, if a file with multiple records is passed through the web
>>interface, after doing the first few records, the perl script just simply
>>suspends.  From the look of the output, it is almost as if it never
>>recieves
>>back a PID from the C program, and so it hangs.
>>
>>But this only happens when i run it via the web interface, so what is
>>happening here!?
>>
>>S
>>
>>_________________________________________________________________
>>MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*.
>>http://join.msn.com/?page=features/virus
>>
>>___________________________________________________________________________
>>
>>To unsubscribe, send email to [email protected] and include in the
>>body
>>of the message "signoff SERVLET-INTEREST".
>>
>>Archives: http://archives.java.sun.com/archives/servlet-interest.html
>>Resources: http://java.sun.com/products/servlet/external-resources.html
>>LISTSERV Help: http://www.lsoft.com/manuals/user/user.html
>>
>
>___________________________________________________________________________
>To unsubscribe, send email to [email protected] and include in the body
>of the message "signoff SERVLET-INTEREST".
>
>Archives: http://archives.java.sun.com/archives/servlet-interest.html
>Resources: http://java.sun.com/products/servlet/external-resources.html
>LISTSERV Help: http://www.lsoft.com/manuals/user/user.html


_________________________________________________________________
The new MSN 8: advanced junk mail protection and 2 months FREE*
http://join.msn.com/?page=features/junkmail

___________________________________________________________________________
To unsubscribe, send email to [email protected] and include in the body
of the message "signoff SERVLET-INTEREST".

Archives: http://archives.java.sun.com/archives/servlet-interest.html
Resources: http://java.sun.com/products/servlet/external-resources.html
LISTSERV Help: http://www.lsoft.com/manuals/user/user.html