diff --git a/include/net/ip.h b/include/net/ip.h
index f41ce07..bb207db 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -166,6 +166,7 @@
 #define NET_ADD_STATS_BH(field, adnd)	SNMP_ADD_STATS_BH(net_statistics, field, adnd)
 #define NET_ADD_STATS_USER(field, adnd)	SNMP_ADD_STATS_USER(net_statistics, field, adnd)
 
+extern unsigned long snmp_fold_field(void *mib[], int offt);
 extern int snmp_mib_init(void *ptr[2], size_t mibsize, size_t mibalign);
 extern void snmp_mib_free(void *ptr[2]);