pub unsafe extern "C" fn im_matcat(
top: *mut DOUBLEMASK,
bottom: *mut DOUBLEMASK,
filename: *const c_char
) -> *mut DOUBLEMASK
pub unsafe extern "C" fn im_matcat(
top: *mut DOUBLEMASK,
bottom: *mut DOUBLEMASK,
filename: *const c_char
) -> *mut DOUBLEMASK