Personally I hate using platform specific modules if I can avoid it. When you start with a nice portable language, it is worth a little effort to not lose portability.

The key to my approach is the IPC::Open3 module and the wait command. The module exports open3, which lets you launch a process with specified STDIN, STDOUT, and STDERR. The return of that is a process ID. Conversely wait will collect the return of a process you launched (the processes are called "children" and this is called "reaping the process" since it is the last step before the process can finish dying) returning the process ID and setting $? to its return code.

What I did is launched processes hooked directly to my output but supressing all input (because there is no easy way to sort out you being able to talk to 5 processes at once on one pipe) and kept track of what I launched. When I reaped them if there was a problem I would give a message based on what I had. My logic was complicated by the fact that I might have 200 jobs to launch, but don't want to run more than 5 at a time. However that is the idea.

See if you can't get that to work. If you do you will both have more portable code and will have learned a lot about process communication..both good things IMO. :-)