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Accessing Common Registry Settings on Windows
On Windows, it is possible for a key to have both a value and subkeys. Its default value is accessed by using "Default" or "." in place of a subkey:
settings.setValue("HKEY_CURRENT_USER\\MySoft\\Star Runner\\Galaxy", "Milkyway");
settings.setValue("HKEY_CURRENT_USER\\MySoft\\Star Runner\\Galaxy\\Sun", "OurStar");
settings.value("HKEY_CURRENT_USER\\MySoft\\Star Runner\\Galaxy\\Default"); // returns "Milkyway"
On other platforms than Windows, "Default" and "." would be treated as regular subkeys.
