ABSTRACT
Writing a VxD, however, is a different matter, because a VxD runs in a supervisor context — meaning it runs outside of any of the virtual machines. In fact, a VxD becomes a part of the software which implements the virtual machine. Thus, the VxD writer needs a more complete understanding of how the virtual environment differs from the physical environment and how Windows creates the illusion of the virtual machine. A full understanding of the virtual machine is especially important to pro grammers who are developing VxDs that need to manipulate resources in an applica tion’s virtual environment, as many are.
