Function - Set target thread's scheduling policy state.
[in thread send right]
The thread scheduling policy is to be set.
Policy to be set. The values currently defined are POLICY_TIMESHARE,
POLICY_RR (round robin) and POLICY_FIFO (firstin, first-out).
[pointer to in structure]
Base scheduling policy specific data,
policy_fifo_base, policy_rr_base or policy_timeshare_base.
The size of the buffer (in natural-sized units).
True if the thread's scheduling limits should be restricted to
allow no more service than specified by base.
The thread_policy function sets the scheduling policy
to be applied to thread. policy must be a scheduling policy
currently "enabled" for the thread's assigned processor set.
The processor set to which thread is currently assigned does
not currently enable policy.
The specified scheduling attributes exceeds the thread's limits.