Directed_Sys_Control

include vmm.inc

mov     ecx, DDB
VMMCall Directed_Sys_Control
 

Jumps to the VxD's device-control procedure. Use this service instead of calling the control procedure directly.

• Return value depends on the message sent to the virtual device.

DDB

VxD's DDB (Device Description Block) that contains device control procedure. All other registers are passed unaltered to the control procedure.