The question is ambiguous and misleading or just simply nonsensical.

This sort of thing is sadly common in interviews, where the interviewer some arbitrary answer in mind and expects you to read his mind, which is possible only some of the time.

By definition you can't sort an infinite list. You've conveniently turned the question, in your mind, into something like "how do you efficiently maintain an ordered list of incoming items?"

It's honestly pretty ridiculous seeing your tone in the comments and how you think that highly about your bad interview questions and your flawed conceptions about the solutions, including CSV and TSV confusion. This smile makes it embarrassing even.

Hope I never pass your interview!

Or pass the interview if it was a management role