Re: Deploying new versions [Was: Versioning HTML at the server]

Chris Lilley, Computer Graphics Unit (
Mon, 31 Oct 1994 11:32:55 +0100

(This is actually Marc VanHeyningen's reply to my message. I am trying to get it
onto www-talk, again)

===== Marc's stuff below ========
(Is it just me, or is the www-talk list dead?)

You said:
>> Most of them are not smart
>> enough to parse content-types according to MIME rules
>Then perhaps it is about time that the browsers _did_ parse
>things according to the MIME rules. Like the mailcap file for
>instance; our site has two. One for metamail and one for
>Mosaic and Netscape to use. I have not tried putting a copy
>of the metamail one where Arena can see it; maybee I should.

I absolutely agree; I've tried to suggest that handling MIME stuff to
a reasonable degree is important in browsers, and been trying to make
mailcaps more friendly to the needs of WWW browsers. Most current
browsers understand mailcaps at a very crude level; for instance, they
don't understand the "test" clause (Netscape and Lynx do; Mosaic
doesn't. Haven't tried Arena.)

Unfortunately, it's a little late; virtually every existing browser
will barf on parameters in content-types, and even if these errors are
fixed tomorrow (which I've seen little sign they will be, I pointed
out this problem a couple times months ago and have seen no progress
towards fixing it) it'll be a problem for years.

Clearly we need some way to indicate parameter constraints with
Accept: headers; something like "Accept: text/html; version=3.1" or
the like. Tolerant servers could not include version parameters on
clients that don't indicate them in Accept: headers. Not a good
solution, but I don't know a better one.

- Marc

Marc VanHeyningen  <>