I'd like to see some comparison with the STREAMS layered/stackable API from SVR4 which let a developer do just the sort of layering this API proposes. What make

I'd like to see some comparison with the STREAMS layered/stackable API from SVR4 which let a developer do just the sort of layering this API proposes. What makes it better than STREAMS, does it share the same pitfalls, etc.?