Int 15 Fn 101A  - Topview - "ostack" - Switch To Task's Internal Stack     [Q]

   AX = 101Ah

Return: stack switched

Notes: this call may not be nested; a second call must be preceded by a call
     to "USTACK" (AX=1025h)
   while TopView requires many API calls to be executed while on the
     task's internal stack, DESQview allows those calls to be executed
     regardless of the current stack

See Also: AX=1025h