My current project involves building a lot of executable files, each
with custom settings in a header that uses the project configuration:

#ifdef _FOO1
 #define bar foobaz
 #define foo foobar
#endif

_FOO1 is defined via the project configuration.

Within this, I would like to add a #define OUTPUT_FILE "FOO1.exe", and
then programmatically set the linker's /OUT flag to OUTPUT_FILE.

MSDN directs me to import VCProjectEngine.dll, which has an
OutputFile.set() function, but I cannot find any example of this for
VC anywhere (the example they provide is in VB, which I am not fluent
in, and have not been able to translate to VC).

Their example:
Public Module Module1
   Sub Test()
       Dim prj As VCProject
       Dim cfgs, tools As IVCCollection
       Dim cfg As VCConfiguration
       Dim tool As VCLinkerTool
       prj = DTE.Solution.Projects.Item(1).Object
       cfgs = prj.Configurations
       cfg = cfgs.Item(1)
       tool = cfg.Tools("VCLinkerTool")
       tool.<b>OutputFile</b> = "$(ProjectName).x"
   End Sub
End Module

I have tried instantiating a VCProject object, a VCLinkerTool object,
a VCConfiguration object, etc, to no avail ("cannot instantiate
abstract class due to following members: 'HRESULT
IUnknown::QueryInterface(const IID &_void **)'  : is abstract")

Can anybody help me out?  There has to be a simple way to set the
OutputFile programmatically.

Thank you for your time,

~Shane