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include vmm.inc
 
mov     ebx, SysVM                  ; system VM handle
mov     esi, OFFSET32 CommandTail   ; points to WIN386 command tail
mov     eax, Sys_Critical_Init
VMMcall System_Control
 
The Sys_Critical_Init message notifies the virtual device that Windows is
starting. The system sends this message to direct virtual devices to carry
out, as quickly as possible, the minimum number of tasks needed to prepare
the device for enabled interrupts. While virtual devices process this
message, interrupts are disabled.
 
Parameter    Description
────────────────────────────────────────────────────────────────────────────
 
SysVM        Specifies a handle identifying the system virtual machine.
 
CommandTail  Points to the command tail retrieved from the program segment
             prefix (PSP) of WIN386.EXE. The first byte in the command tail
             specifies the length in bytes of the tail.
 
Return Value
 
The carry flag is clear if the virtual device initialized successfully.
Otherwise, the carry flag is set to prevent the system from loading the
virtual device.
 
Comments
 
While processing this message, virtual devices typically initialize any
critical functions needed to support interrupts and claim any V86 pages
required to support the device. For example, the virtual display device
claims the video memory. If a virtual device provides services, it should
initialize any data associated with those services.
 
The virtual device must not use the Simulate_Int or Exec_Int services.
 
Uses
 
Flags
 
See Also
 
Device_Init, Sys_Critical_Exit
 
 
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