    C:\>scons -Q OS=windows
    Install file: "build/windows/world/world.h" as "export/windows/include/world.h"
    cl /Fobuild\windows\hello\hello.obj /c build\windows\hello\hello.c /nologo /Iexport\windows\include
    cl /Fobuild\windows\world\world.obj /c build\windows\world\world.c /nologo /Iexport\windows\include
    lib /nologo /OUT:build\windows\world\world.lib build\windows\world\world.obj
    Install file: "build/windows/world/world.lib" as "export/windows/lib/world.lib"
    link /nologo /OUT:build\windows\hello\hello.exe /LIBPATH:export\windows\lib world.lib build\windows\hello\hello.obj
    embedManifestExeCheck(target, source, env)
    Install file: "build/windows/hello/hello.exe" as "export/windows/bin/hello.exe"