On 2019 Jan 15 17:51:46, you wrote to me:

 ml>> systems that display the message's written time in local time or UTC
 ml>> if configured to do so

 MK> I've yet to see any BBS get that right if indeed the BBS software can
 MK> be configured to do so.

i didn't say anyting about a BBS 

 MK> Do you have or know of a working example that indeed gets it right?

i've known of several over the years... i think Synchronet BBS does but i
haven't looked very closely to see for sure... i'm not positive but maybe some
of the sysop readers like golded and timed... i know i've seen the capability
in the past because it was interesting to read a message that had only been
posted minutes before and i was able to tell this because the "date written"
displayed in the reader i was using was my local time and the writer was
several timezones removed... looking at the raw message showed the actual date
stored in the message...

 ml>> you cannot convert to/from local/UTC if the TZ isn't known

 MK> Understood.  Speaking for myself, I have never bothered and don't use the
 MK> FTN datetime for anything, nevermind converting it even if only display
 MK> purposes.  What I was taught AGES ago is the data is the data even when it
 MK> is obviously wrong, and that to tamper with raw data is EXTREMELY
 MK> vorbotten.

we're not tampering with anything... we taking one set of time representation
numbers and adjusting them to local or UTC time... it is a simple thing to do
if all the necessary parts are available...

 MK> If I cared, for local display I would do something like this (using
 MK> the datetime and TZUTC from "MSGID: 1:3634/12.73 5c3e3137";

yes, i'm very familiar with the date command... i normally use it for something
 like this...

  blahblah | tee $(date +%Y%m%d%H%M%SUTC%z)-blahblah.log

depending on the processing being logged, "%S" may be left out... and then
there's a majikal

  $(date +%j)

that one might find useful when dealing with FTN nodelists and similar other
things that need the DOY for their work 

)\/(ark

Always Mount a Scratch Monkey
Do you manage your own servers? If you are not running an IDS/IPS yer doin' it
wrong...
... A single great deed can be undone by the sum of many small actions.
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 * Origin:  (1:3634/12.73)