in-kernel priority is used. Reported by <drochner>.
Minor fixes for scheduling calls to conform the POSIX:
- If pid is equal to zero, use the calling process;
- In case of permission problem, return EPERM instead of EACESS;
- sched_setscheduler() should return previously used policy;
- pthread_* calls should return the error code or zero;
Should fix the namespace problems (and builds of some packages):
- Move cpuset_t defintion from pset.h to sched.h;
- Remove the #include of pset.h in pthread.h;
b5e9addd22