[Boost-users] [geometry] how to set number of points / chord length in buffer() join_round strategy?

I see in the released buffer() algorithm, there is a chord length argument: void buffer(Input const & geometry_in, Output & geometry_out, Distance const & distance, Distance const & chord_length = -1) But I can't seem to find an equivalent for buffer_inserter<> with a join_round strategy. How do I set the chord length or number of approximating points? John Lilley