Function FreeImage_OpenMultiBitmap 

pub unsafe extern "C" fn FreeImage_OpenMultiBitmap(
    fif: FREE_IMAGE_FORMAT,
    filename: *const c_char,
    create_new: BOOL,
    read_only: BOOL,
    keep_cache_in_memory: BOOL,
    flags: c_int,
) -> *mut FIMULTIBITMAP