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include vmm.inc
 
VMMcall Begin_Nest_V86_Exec
 
The Begin_Nest_V86_Exec service sets the current virtual machine to V86 mode
and prepares the virtual machine for nested execution. This service is used
in conjunction with the End_Nest_Exec service to create a nested execution
block in which a virtual device may call the Exec_Int and Resume_Exec
services. Virtual devices use these services to call software in the virtual
machine.
 
This service has no parameters.
 
Return Value
 
The Client_CS and Client_IP registers contain a break point used by nested
execution services.
 
Comments
 
When in a nested execution block, a virtual device may call the Exec_Int and
Resume_Exec services any number of times.
 
This service should only be used by virtual devices that convert
protected-mode calls into V86 calls. For example, the virtual MS-DOS manager
uses this service to map calls to MS-DOS functions (Interrupt 21h) issued by
protected-mode programs into calls to MS-DOS functions in V86 mode.
 
This service saves the current execution mode of the virtual machine and
End_Nest_Exec restores the mode.
 
Uses
 
Client_CS, Client_IP, Flags
 
See Also
 
Begin_Nest_Exec, End_Nest_Exec
 
 
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