On Fri, Feb 22, 2013 at 04:57:42PM +1100, Mark Andrews wrote:
RFC 952 as modified by RFC 1123 describe the legal syntax of a hostname. There is no trailing period.
Mark is of course correct about this, but it doesn't fully help. The basic problem is (as always) the confusion about the difference between a hostname and a fully-qualified domain name, which so happens to be also a hostname. Whether we like it or not, this ambiguity is no longer something that can be resolved. What you have to do is know whether you are dealing with a hostname (no final dot, because the hostname syntax doesn't use it), a domain name relative to the root (no final dot, because implicitly you're not using the search path; it is nearly impossible to tell the difference between this and a host name), a domain name relative to something else, relying on your search path (bad, evil, and wrong, just stop it or you get what you deserve), or an actually fully-qualified domain name (final dot). The second of these is about to get harder to distinguish from the third, because of the new gTLD programme at ICANN. I wish there were a neat answer to the problem. There isn't. A -- Andrew Sullivan Dyn, Inc. asullivan@dyn.com v: +1 603 663 0448