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include vmm.inc
 
mov     eax, Interrupt      ; interrupt number
mov     edx, Type           ; zero for trap gate, nonzero for interrupt gate
VMMcall Set_PM_Int_Type
 
The Set_PM_Int_Type service sets the gate type for a protected-mode
interrupt vector.
 
Parameter  Description
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Interrupt  Specifies the number of the interrupt to set.
 
Type       Specifies the type of gate to set. If this parameter is zero, the
           service sets a trap gate; if nonzero, it sets an interrupt gate.
 
Return Value
 
This service has no return value.
 
Comments
 
An interrupt through an interrupt gate automatically clears the interrupt
flag bit to disable interrupts. Interrupts through trap gate do not modify
the interrupt bit. All protected-mode interrupts default to the trap gate
type, but virtual devices such as the virtual PIC device, may change some
trap gates to interrupt gates so that hardware interrupts disable
interrupts. The virtual PIC device leaves software interrupts, such as
Interrupt 21h, unchanged. This avoids an unnecessary ring transition by
eliminating the need for the software interrupt handlers to execute an sti
instruction.
 
Uses
 
Flags
 
See Also
 
Get_PM_Int_Type, Set_PM_Int_Vector
 
 
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