NOTE: As noted below, I will not be updating this. Interest for it has been nonexistant and I think LittleOBJLoader is a better solution for our purposes.
Although loadobj.c in the lab material is very tight and simple and great for its purpose, it can not handle all models, in particular not multi-shape models which the OBJ format supports.
An alternative that you may want to check out is TinyObjLoader. It is a lot bigger than loadobj, but that comes with more features, supporting more of the format.
One thing that it does not have is a really small and tight demo, and of course it didn’t have one based on my course material. This demo solves both problems! It is the smallest TOL demo by far, and it plugs right into our pipeline!
PS: After writing this demo, I also updated the limited loadobj.c, which is now renamed LittleOBJLoader, which is smaller than TOL, and according to my tests just as capable! :) Therefore, I see little reason to work more on this demo.