find_inet_addr
if ((res0 = find_inet_addr(host, 0)) == NULL)
struct addrinfo *find_inet_addr(char *, int);
res = find_inet_addr(pat, AI_NUMERICHOST);
if ((res0 = find_inet_addr(server, 0)) == NULL)
res0 = find_inet_addr(client, AI_NUMERICHOST);
if ((res0 = find_inet_addr(client, 0)) == NULL)