9 Iterators library [iterators]

9.8 Stream iterators [iterators.stream]

9.8.3 Class template istreambuf_iterator [istreambuf.iterator]

9.8.3.5 istreambuf_iterator::equal [istreambuf.iterator::equal]

bool equal(const istreambuf_iterator& b) const;

Returns: true if and only if both iterators are at end-of-stream, or neither is at end-of-stream, regardless of what streambuf object they use.