cpuset_t vs. cpu_set_t

Hi all,

I noticed that the recently added sys/pset.h defines a cpuset_t type, and
the int   pthread_setaffinity_np(pthread_t, size_t, cpuset_t *);
function.

On a Linux 2.6, I can find the cpu_set_t type, and
int pthreadr_setaffinity_np(pthread_t, size_t, cpu_set_t *);

What is the correct type name? (from a POSIX p.o.v. I mean).