The problem is that Parallel::Jobs::start_job takes an external program to run as an argument.

You're passing it a reference the result of invoking hello() or middle(), a reference to 1 in both cases (the result of print).

It looks like P::J::s_j is smart enough to dereference that scalar reference, so it tries to run the program "1", and doesn't find it...

You probably want to read the docs again.

The STDIN => *HANDLE notation means that you can pass an open filehandle in to the start_jobs routine, which the called program will use for input.

The outputs can either be fed to handles of their own, OR be passed back to your program. If you choose the capture option, then you'll get the outputs as events when you watch_jobs.

It would look like this:

open(SCRIPT, "<", "script.txt") or die "Can't open script.txt, error $
+!";
Parallel::Fork::start_job("bc", stdin_handle => *SCRIPT,
                          stdout_capture=>1, stderr_capture=>1);
[download]

This would make the "bc" calculator program execute your script, and let you read the results with watch_jobs.
--
Mike