Description

   This routine obtains both the current scheduling policy and
   associated scheduling parameters of the thread specified by the
   thread argument.

   The priority value returned in the param structure is the value
   specified either in the attr argument passed to pthread_create()
   or by the most recent call to pthread_setschedparam() that
   affects the target thread.

   This routine differs from pthread_attr_getschedpolicy() and
   pthread_attr_getschedparam(), in that those routines get the
   scheduling policy and parameter attributes that are used to
   establish the priority and scheduling policy of a new thread
   when it is created. This routine, however, obtains the scheduling
   policy and parameters of an existing thread.