KERNEL DESIGN ISSUES - Hard Real-Time Computing Systems: Predictable Scheduling Algorithms and Applications - page 379

There are two primitives for terminating a process: the first, called end process , di-
rectly operates on the calling task; the other one, called kill , terminates the task passed
as a formal parameter. Note that if the task is HARD, it is not immediately removed
from the system but put in ZOMBIE state. In this case, the complete removal will be
done by the timer routine at the end of the current period:
/*-----------------------------------------------------------*/
/* end process -- terminates the running task */
/*-----------------------------------------------------------*/
void end process (void)
{ <disable cpu interrupts>
if (vdes[pexe].type == HARD)
insert(pexe, &zombie);
else vdes[pexe].state = FREE;
insert(pexe, &freetcb);
dispatch();
load context();
}