Re: [apps-discuss] "X-" revisited

Frank Ellermann <> Thu, 30 June 2011 07:19 UTC

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From: Frank Ellermann <>
Date: Thu, 30 Jun 2011 09:19:21 +0200
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To: Peter Saint-Andre <>
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Subject: Re: [apps-discuss] "X-" revisited
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On 27 June 2011 20:36, Peter Saint-Andre wrote:

> I've published a heavily-revised version of the "X-" proposal

Thanks.  The worst case I'm aware of is image/x-icon vs. MIME type
image/ - add this if you need more bad examples.

Maybe pick some well-known RFCs and honour them with an "updates",
obsoleting their x-foo conventions.

IIRC the NetNews RFC also inherited this x-cruft.  As Dave wrote,
I also considered "x-foo" as cool idea, but it turned out to work
like "bar", and we need no "x-" to arrive at "foobar".

Wrt RFC 5064, as long as the relevant message format / mail /
netnews / MIME / http / etc. RFCs are not updated a BCP calling
for updates doesn't help, and developers will continue to invent
new x-cruft, because it's their only "officially allowed" option.

It could be also tricky to fix x-issues in the future message
format and mail STDs, because STDs are not supposed to be very
different from the DS.  A newer BCP overruling the older DS with
an "updates" could justify to adopt the new state of the art in
the STD.  Or maybe I'm just a bit paranoid... ;-)