Function esp_wifi_register_if_rxcb 

pub unsafe extern "C" fn esp_wifi_register_if_rxcb(
    ifx: *mut wifi_netif_driver,
    fn_: Option<unsafe extern "C" fn(*mut esp_netif_obj, *mut c_void, usize, *mut c_void) -> i32>,
    arg: *mut c_void,
) -> i32

@brief Register interface receive callback function with argument

@param[in] ifx pointer to wifi interface handle @param[in] fn function to be registered (typically esp_netif_receive) @param[in] arg argument to be supplied to registered function (typically esp_netif ptr)

@return ESP_OK on success