Assuming you use IVI-COM and IVI-C drivers in mixture, the simplest solution is write language-based wrappers, that are all common style wrapping your IVI-COM and IVI-C. For example (assuming you use VC++), you can write CIviDriver abstract class with InitWithOptions() and Close() and some other necessary methods and data members that can be applied to all the drivers. Then write model-specific wrapper classes such as CYourInstr class, which is derived from CIviDriver, then add model-specific wrapper methods. This approach can be used not only for C++, but C# and VB.NET can also be okay. By this approach, your app will be able to handle all the drivers as a collection or array of multiple CIviDriver instances.
Or, other way is write a "pseudo" IVI-COM thin wrapper DLL for the IVI-C. (Applicable only if you have skill to write ATL COM DLL with VC++.) Although this COM DLL is ***not fully*** complant with IVI-COM spec, you can treat it as if it was a true IVI-COM driver. Actually, create an ATL COM DLL project, then add a component class such as CYourInstr with IYourInstr interface (IDL is auto-generated). Add import directive to IDL and #import to stdafx.h to import typilib part from "IviDriverTypeLib.DLL" Then hand-edit the IDL so that your IYourInstr interface is derived from IIviDriver rather than IUnknwon. Hand-edit the C++'s CYourInstr class header and add IIviDriver, IIviDriver, IIviDriverUtility, IIviDriverIdentity, IIviDriverOperation as its base interface classes being inherited. Finally you will have to add 10 ~ 20 additional method (of IIviXXXX interfaces that you added) to build the DLL without compile error. Actual implementation of the DLL will be probably redirection code to the IVI-C driver. By this approach, all the drivers can be handled as a collection or array of IIviDriverPtr (smart ptr of C++) objects.
