Using a mac system font in TTF_OpenFont()

is there a way to pass for instance ?Arial? WITHOUT having to include the Arial.ttf in my bundle ?

I would like the users to be able to pick any system font available on their computer

I?ve read as much as I could about NSFontManager and this call :

NSMutableArray * fontList = [[NSMutableArray alloc] initWithArray:[[NSFontManager sharedFontManager] availableFontFamilies]];

gives me a list of available fonts, but simply passing one of these strings to TTF_openFont won?t work since it isn?t a full path. And I have no idea how to figure out where each font of these families is stored (could be /Library/Fonts but also ~/Library/Fonts)

any hints ?