Function objc_sys::protocol_addProperty

pub unsafe extern "C" fn protocol_addProperty(
    proto: *mut objc_protocol,
    name: *const c_char,
    attributes: *const objc_property_attribute_t,
    attributes_len: c_uint,
    is_required_property: BOOL,
    is_instance_property: BOOL
)

Available on non-objfw only.