Determine calling application GUID

I want to add a form of access security to a DLL that I created and I was hoping to restrict within the code a check of the calling application's GUID. I cannot seem to find a way to retrieve the calling app's GUID to verify if it has access.

Is this even possible, and if so could someone pr开发者_如何学运维ovide a code snippet on how to determine the GUID?

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I found my answer...here is an example in VB:

    Dim asm As Assembly = Assembly.GetExecutingAssembly()
    Dim attribs = (asm.GetCustomAttributes(GetType(GuidAttribute), True))
    MsgBox(DirectCast(attribs(0), GuidAttribute).Value.ToUpper)

This provides the calling application's GUID.