int in_addr_default_prefixlen(const struct in_addr *addr, unsigned char *prefixlen);
int in_addr_default_subnet_mask(const struct in_addr *addr, struct in_addr *mask);
int in_addr_mask(int family, union in_addr_union *addr, unsigned char prefixlen);
+int in_addr_prefix_from_string(const char *p, int family, union in_addr_union *ret_prefix, uint8_t *ret_prefixlen);
static inline size_t FAMILY_ADDRESS_SIZE(int family) {
assert(family == AF_INET || family == AF_INET6);