OS_TYPE Enumeration

The OS_TYPE enumeration specifies information about the operating system (OS) type for use with Server Handle Key Values (section<169>

 typedef  enum 
   VER_NT_WORKSTATION = 0x00000001,
   VER_NT_SERVER = 0x00000003

VER_NT_WORKSTATION:  The OS is a Windows NT operating system workstation.

VER_NT_DOMAIN_CONTROLLER:  The OS is a Windows NT domain controller.

VER_NT_SERVER:  The OS is a Windows NT server. A server that is also a domain controller is reported as VER_NT_DOMAIN_CONTROLLER, not VER_NT_SERVER.