getline() works for (single) character delimited reads and lets you use a std::string. The latter is reason enough to use it: it means you don't have to worry about manual dynamic memory allocation and have zero risk of overflows.

In any case, the C++ equivalent to fgets is sgetn on the underlying streambuf or filebuf - http://en.cppreference.com/w/cpp/io/basic_streambuf/sgetn . I'd use this before I used fgets, if for no other reason than I then don't have to remember to call fclose()

The fact that you haven't used one of the most trivial functions in the standard library because of a slight performance penalty 15 years ago is worrying.