Re[2]: [Oslib-devel] how to...

[Juras B. <yb...@tu...>]

Hello Luca,

Friday, February 28, 2003, 4:13:12 PM, you wrote:

LA> Ok, I hope this clarified things a little bit... If your scheduler is
LA> driven by the timer interrupt, I would simply avoid to invoke it if the
LA> interrupted task is the vm86 task.

Do you mean something like this:

void mytimerhandler()
{
 if (vm86task)
  {
   // jump to vm86 timer handler through real mode interrupt table
   // by setting VM86 task's CS:IP pointer, pushing flags etc.
   return;
  }

  // switch to the next task in the scheduler's queue and
  // handle timer interrupt for 32-bit OS needs

}

?

I think this will HALT the task-switching mechanism while a VM86-task is not
yet finished and paralyze the system...

But maybe I should handle an interrupt twice, i.e. emulate interrupt for VM86
task (pushing flags, setting CS:IP...) and handle the interrupt as usual for OS
needs?



-- 
Best regards,
 Juras                            mailto:yb...@tu...