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From: Warner Losh <imp@bsdimp.com>
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Date: Fri, 8 Apr 2011 11:43:16 -0600
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Cc: FreeBSD Hackers <freebsd-hackers@freebsd.org>,
	Sergey Vinogradov <boogie@lazybytes.org>
Subject: Re: ifconfig output: ipv4 netmask format
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On Apr 8, 2011, at 9:55 AM, Mike Bristow wrote:

> On Fri, Apr 08, 2011 at 07:40:56PM +0400, Sergey Vinogradov wrote:
>> On 08.04.2011 19:23, Warner Losh wrote:
>>> On Apr 8, 2011, at 6:08 AM, Sergey Vinogradov wrote:
>>> If we really wanted to make it human readable, we'd output 10.2.3.4/24
>> 
>> So, maybe, while following the POLA, we should add an option, as Daniel 
>> mentioned above? To output the CIDR?
> 
> Non-contigous netmasks are legal in IPv4.  What do you do if someone adds
> the CIDR flag but the netmask cannot be represented in CIDR notation?

They have become illegal in the fullness of time.

Warner