Fix multithreading example #221

Also, all examples run and work except the multi-threading one, which compiles but doesn't work most of the time and I'm not sure why. Help appreciated here!

Was this merged before fixing the multi threading example? If that is the case, that is fine, but if it's broken I'd like to make sure an issue is opened to track that

Yes, the multi-threading example is still broken.

Originally posted by @AnErrupTion in #220 (comment)