Return the number of lines that scrolled to above the top of terminal {buf}. This is the offset between the row number used for |term_getline()| and |getline()|, so that: term_getline(buf, N) is equal to: getline(N + term_getscrolled(buf)) (if that line exists). {buf} is used as with |term_getsize()|. Can also be used as a |method|: GetBufnr()->term_getscrolled()