Re: without message queue

Arkady Frenkel wrote:
Correct , that general purpose OS so it can't allow some thread to catch all CPU forever ( thread starvation used for the same purpose too ) , opposite to RT oses,like windows CE,when setting highest priority for some running thread stop all ( even system ) other threads execution

That's also true of XP, it's just that it only implements one of the usual scheduling models, namely round-robin, whereas other OSes generally include FIFO, LIFO and possibly others. While you are running a priority 31 thread, all lower priority threads (including system threads) will not run - the mouse pointer freezes for example.

Obviously, XP has additional problems that prevent it from being used very successfully as an RTOS, such as a lack of priority inheritance.