Re: Question/comment regarding RFC1123 hostnames
Phil Karn <karn@qualcomm.com> Fri, 24 December 1993 07:35 UTC
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Date: Thu, 23 Dec 1993 23:16:02 -0800
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From: Phil Karn <karn@qualcomm.com>
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To: braden@isi.edu
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In-Reply-To: <199312231922.AA04209@zephyr.isi.edu> (braden@ISI.EDU)
Subject: Re: Question/comment regarding RFC1123 hostnames
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The rule I've used for some time with good results is the following: if the argument to the lookup routine consists entirely of decimal digits and dots, then it's an IP address in dotted decimal form. Otherwise it's a domain name, possibly abbreviated. I suppose the rule could be extended to require at least one dot for it to be considered an IP address. Phil