Path: utzoo!utstat!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!shadooby!sharkey!cfctech!teemc!ka3ovk!drilex!dricejb
From: dricejb@drilex.UUCP (Craig Jackson drilex1)
Newsgroups: news.software.b
Subject: Re: Is anyone interested in putting local time in the "Date:" header?
Message-ID: <6420@drilex.UUCP>
Date: 30 Nov 89 14:35:31 GMT
References: <14749@well.UUCP>
Reply-To: dricejb@drilex.UUCP (Craig Jackson drilex1)
Organization: DRI/McGraw-Hill, Lexington, MA
Lines: 62

In article <14749@well.UUCP> Jef Poskanzer <jef@well.sf.ca.us> writes:
>I'll be posting patches to add a checksum header sometime soon, but
>meanwhile here's something else to discuss.  News articles currently
>put GMT in the "Date:" header.  This may even be required by the news
>RFC, I don't know.  It is obviously not required by the mail RFC that
>the news one is built on.  But RFC or no RFC, it seems to me that it
>would be better if the date were in the local time at the originating
>machine.  The reasoning is twofold:
>
>1) It's easy to go from local times to GMT, but it's impossible to go
>from GMT to the appropriate local time since you don't know which one
>is appropriate.  Thus if people started posting in local time but someone
>absolutely had to see GMT, he could easily modify his newsreaders to
>parse the date field and convert.  In other words, it doesn't break
>anything (too badly).

This is not true.  There is no universally accepted list of local time
abbreviations.  The classic example is "BST"--it can either mean
"British Summer Time" or "Bering Standard Time" (in the regions around
the Bering Strait).

The only way they could be easily convertable is if there were a
minutes-from-GMT field included as well.

In addition, "GMT" is all you can count on when the OS is Unix--by definition.
If the kernel hasn't been reconfigured and the system isn't running ADO's
time-conversion package, then the local time is likely to be off.
If it's an older Unix system, the local time is likely to be off where
the local legislature has changed the rules.

I quote "GMT" above because Unix time is only *defined* as GMT.  That
doesn't mean that the clocks are set right.

>2) Displaying the time in GMT is of limited utility - the only reason
>for it that I can think of is to enable a human to tell the posting
>order of a set of messages, but who does that kind of thing manually?

You have a point here--I've often looked at the Date header, then looked
at the organization line for a location, and tried to interpolate a
timezone to figure out what the local time of the poster was.

>On the other hand, displaying local time would be very useful.  In
>local-distribution newsgroups, there is no reason to use anything
>else.  In world-wide newsgroups, local time might tell you that a
>message was posted at 4 in the morning, explaining its lack of
>coherence.

How do you know that the poster isn't really on the night shift, about
ready for dinner?

>Am I missing anything, or should I go ahead and post the patches?

I don't think it would be a good idea--unless your patches merely added
a local-time offset to the headers.

>  Jef Poskanzer  jef@well.sf.ca.us  {ucbvax, apple, hplabs}!well!jef


-- 
Craig Jackson
dricejb@drilex.dri.mgh.com
{bbn,axiom,redsox,atexnet,ka3ovk}!drilex!{dricej,dricejb}