pub unsafe extern "C-unwind" fn CFURLCreateWithFileSystemPathRelativeToBase(
allocator: Option<&CFAllocator>,
file_path: Option<&CFString>,
path_style: CFURLPathStyle,
is_directory: bool,
base_url: Option<&CFURL>,
) -> Option<CFRetained<CFURL>>Available on crate features
CFBase and CFURL only.