[Twisted-Python] twisted and threading

I wrapped a c library using swig and was hoping to make use of it in a twisted server I am writing. The issue is that the c library fundamentally blocks waiting for input that may never come. Is there a way from twisted to deal with this cleanly within the framework? I.e. some combination of adding a reactor.addSystemEventTrigger event and calling reactor.threadpool.stop seem like it should work but I haven't had any luck yet. (I saw all the previous posts on this topic, but the recommendations don't seem applicable in my case since the blocking is occurring outside my control in a c library and the blocking call may never return.) Thanks, Steve Bauer