Messages in this thread |  | | From | "H. Peter Anvin" <> | Subject | Re: notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias bug 2.4.9 and 2.2.19] | Date | 6 Sep 2001 11:23:29 -0700 |
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Followup to: <20010906173948.502BFBC06C@spike.porcupine.org> By author: wietse@porcupine.org (Wietse Venema) In newsgroup: linux.dev.kernel > > The SMTP RFC requires that user@[ip.address] is correctly recognized > as a final destination. This requires that Linux provides the MTA > with information about IP addresses that correspond with INADDR_ANY. > > I am susprised that it is not possible to ask such information up > front (same with netmasks), and that an application has to actually > query a complex oracle, again and again, for every IP address. >
In autofs, I use the following technique to determine if the IP number for a host is local (and therefore vfsbinds can be used rather than NFS mounts):
connect a datagram socket (which won't produce any actual traffic) to the remote host with INADDR_ANY as the local address, and then query the local address. If the local address is the same as the remote address, the address is local.
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