| lwIP
    2.1.2
    Lightweight IP stack | 
#include <netif.h>
| Data Fields | |
| const ip_addr_t * | old_address | 
Args to LWIP_NSC_IPV4_ADDRESS_CHANGED|LWIP_NSC_IPV4_GATEWAY_CHANGED|LWIP_NSC_IPV4_NETMASK_CHANGED|LWIP_NSC_IPV4_SETTINGS_CHANGED callback
| const ip_addr_t* netif_ext_callback_args_t::ipv4_changed_s::old_address | 
Old IPv4 address