Environment variables in project .includes?

How do I reference environment variables in my project's .includes file? For the environment variable "SDK" I've tied %SDK% and $SDK. How do I reference it?

Try

Code:

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$$(var)

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That doesn't work either. This is what I tried:

Code:

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$$(CC_VC2010)/VC/atlmfc/include

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I added this to my .pro file:

Code:

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message(QTDIR %QTDIR% $QTDIR $$(QTDIR))

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which resulted in this output:

Code:

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Project MESSAGE: QTDIR %QTDIR% $QTDIR C:/Qt/2009.03/qt

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This shows $$(var) worked for me. Maybe I misunderstood what you mean by ".includes file".

I don't know if it's different from a normal project. I have a file that was created with my makefile import project that is (projectname).includes which allows QT Creator to find directories used for code completion and syntax checking.