I went through the joint honours degree in mathematics and computer science at Oxford (that's basically a particularly rigid double major for people unfamiliar

I went through the joint honours degree in mathematics and computer science at Oxford (that's basically a particularly rigid double major for people unfamiliar with the British system). I did not learn C, mostly because I spent a good deal of effort trying to stay as far from actual implementations as possible, but I'm sure it's quite possible for even straight CS students to not learn C. I don't believe that any required courses (which in particular does not include a course on operating systems) use C.