In D21338#464272, @sucanjan_gmail.com wrote:

I'm not sure if I understand you correctly.
This is ping's use of F_NUMERIC flag in pr_addr():

	if (options & F_NUMERIC)
		return inet_ntoa(ina);
	hp = cap_gethostbyaddr(capdns, (char *)&ina, 4, AF_INET);
	if (hp == NULL)
		return inet_ntoa(ina);
	(void)snprintf(buf, sizeof(buf), "%s (%s)", hp->h_name,
	    inet_ntoa(ina));
	return(buf);

and this is ping6's use of F_HOSTNAME in pr_addr():

	if ((options & F_HOSTNAME) == 0)
		flag |= NI_NUMERICHOST;
	if (cap_getnameinfo(capdns, addr, addrlen, buf, sizeof(buf), NULL, 0,
		flag) == 0)
		return (buf);
	else
		return "?";

I'm not sure if I understand you correctly.