Starting an external, independent process from a script

[Henrik Lied]

Hi there!

I'm trying to create a video uploading service (just to learn). The
system is mostly based on Django, but the question I'm looking an
answer for is more related to Python.

So, the user gets to upload a video file. This can either be a mpg,
avi or mp4-file. When the file is saved to its location, I want to
convert it to FLA (Flash Video). I'm currently using Mplayers
Mencoder, and this works great. The Mencoder is retrieved through
running os.system("mencoder variables here")

The problem with this is that the user has to wait until the movie is
done encoding until he can go around with his business. I don't look
upon this as ideal.

So - I want to spawn a new system process. I need some good pointers
on how to do this right.

Any input? :-)

Thanks a lot in advance!