QT supports multithreading. See the QThread class after you visit this website and check out Developer->documentation < http://www.trolltech.com/
There are probably online references regarding processes and threads < http://www.cs.cf.ac.uk/Dave/C/CE.html
>. I can give you a couple book ISBN's that deal with either QT or Linux Programming (which includes theading/processes).
Programming with QT (ISBN: 0596000642).
Linux Programming Bible (ISBN: 0764546570).