I'd like to write a program (I'm flexible on language; C/C++ was my original idea but a scripting language would probably be better) that runs hundreds of programs, but only N = 4 (say) at a time. The idea is to keep all the cores on a multicore machine busy.

How can I do this? In particular, I'd like a library call I can make in some appropriate language that can

• Start a new thread
• Start a command-line process in the thread with arbitrary arguments
• Recognize when the process is complete, return information to the main thread and terminate the helper/slave thread
• Ideally, send and receive information on standard in/out

This seems like a very basic thing to ask; I'm just looking for something that would make this simple. I'm probably going to write many programs like this for various tasks, and I thought it would be good to ask around before diving into something that's not quite appropriate. I started reading about the (new) Python threading earlier before I thought to ask for advice/help.