It would be really handy to add a way to portably kill process groups of 
a process spawned with subprocess.Popen. My project starts a process, 
which then starts other long running processes. Because of this process 
tree, there's no way for me to portably kill all of those processes. 
Would it be possible to extend subprocess with these features? I did 
find someone who's already implemented this [1], and it's working well 
in my project. There was some discussion about adding this, but it seems 
no one actually committed a patch to implement it.

Anyway, I've attached a patch against python3.0's svn branch that 
implements this. I don't have access to windows, so I'm not able to make 
sure that the TerminateJobObject is correct, and works.

[1]: http://benjamin.smedbergs.us/blog/2006-12-11/killableprocesspy/
[2]: http://mail.python.org/pipermail/python-list/2008-April/487588.html