Re: Increasing precision of Last-Modified header to allow sub-second granularity?

"Poul-Henning Kamp" <phk@phk.freebsd.dk> Wed, 01 February 2012 00:31 UTC

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To: Adrien de Croy <adrien@qbik.com>
cc: Julian Reschke <julian.reschke@gmx.de>, David Booth <david@dbooth.org>, ietf-http-wg@w3.org
From: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Subject: Re: Increasing precision of Last-Modified header to allow sub-second granularity?
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In message <4F286012.6040205@qbik.com>, Adrien de Croy writes:

>>>    Last-Modified: Fri, 27 Jan 2012 20:21:10.011483 GMT
>
>the ability to compare against other previous Last-Modified headers.  
>That allows the client to know whether a version supercedes another, 
>rather than having to defer to the server.
>
>I'd be in favour.

Me too.

But there are necessary consequential changes:
	Expires: headers
	Cache-Control: age fields.
	Age: header.
Possibly more.

Have anybody tried sending such dates to see how much code it breaks ?

I would fear a lot of both clients and servers would choke on it.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.