Re: what do jails map 127.0.0.1 to?

Bjoern A. Zeeb wrote:
[good stuff snipped]
>Yes, could do easily but wouldn’t work for my above case, would it?  I
>can help you with the code for v4 and jails if you help me with the code
>for IPv6?
Well, not quite what you volunteered to do, but can you fill in the INET6 code
for this code snippet? (It does what Alan suggested for INET.)


	/*
	 * Find out what IP# localhost maps to and whether or not use of
	 * INET6 is required.  Jails will map 127.0.0.1 to another INET
	 * address.
	 */
	use_inet6 = 0;
	s = socket(PF_INET, SOCK_DGRAM, 0);
	if (s < 0) {
		use_inet6 = 1;
		s = socket(PF_INET6, SOCK_DGRAM, 0);
	}
	if (s < 0)
		err(1, "Can't create a inet/inet6 socket");
	if (use_inet6 != 0) {
		;	/* Needs code... */
	} else {
		memset(&sad, 0, sizeof(sad));
		sad.sin_len = sizeof(sad);
		sad.sin_family = AF_INET;
		sad.sin_addr.s_addr = inet_addr("127.0.0.1");
		sad.sin_port = 0;
		ret = bind(s, (struct sockaddr *)&sad, sizeof(sad));
		if (ret > 0)
			err(1, "Can't bind 127.0.0.1");
		memset(&sad, 0, sizeof(sad));
		slen = sizeof(sad);
		ret = getsockname(s, (struct sockaddr *)&sad, &slen);
		if (ret < 0)
			err(1, "Can't get bound sockaddr");
		printf("locaddr: %s\n", inet_ntoa(sad.sin_addr));
	}

If the IPv4 code isn't sufficient, please let me know. (I think I know how to make
the RPC code use IPv6, but I need to know what IPv6 address to use. I get confused
by link local/site local/… It needs to be an address that is "this machine".

Thanks for your help with this, rick