In uk.transport.london message , Sat, 2
Jan 2016 16:58:52, Richard J. posted:


You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".


--
(c) John Stockton, Surrey, UK. Turnpike v6.05 MIME.
Merlyn Web Site - FAQish topics, acronyms, & links.

Dr J R Stockton wrote:
In uk.transport.london message , Sat, 2
Jan 2016 16:58:52, Richard J. posted:


You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

Well, as we soon learned, the problem wasn't any sort of Y2K issue. But in
any case, Y2K type bugs date from software designed 40 or more years ago,
when every byte mattered; Oyster is far too recent for the designers to
have been trying to save microscopic amounts of memory.

In message
-sept
ember.org, at 23:52:54 on Mon, 4 Jan 2016, Recliner
remarked:
You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

Well, as we soon learned, the problem wasn't any sort of Y2K issue. But in
any case, Y2K type bugs date from software designed 40 or more years ago,

Nope, plenty of things which actually failed were much more recent than
that.

when every byte mattered; Oyster is far too recent for the designers to
have been trying to save microscopic amounts of memory.

That doesn't explain why the NCT Smartcards broke on 1/1/2006.
--
Roland Perry

In message
-sept
ember.org, at 23:52:54 on Mon, 4 Jan 2016, Recliner
remarked:

Y2K type bugs date from software designed 40 or more years ago

Here's another I came across by chance today:

http://www.theregister.co.uk/2012/03...day_confirmed/
--
Roland Perry

Roland Perry wrote:
In message
-sept
ember.org, at 23:52:54 on Mon, 4 Jan 2016, Recliner
remarked:

Y2K type bugs date from software designed 40 or more years ago

Here's another I came across by chance today:

http://www.theregister.co.uk/2012/03...day_confirmed/

Wonderful! I'm pretty sure that even my distinctly amateurish code does
date checks in a smarter way than that (just subtract a date from today and
see if the answer is greater than 365 -- the system clock at least should
know all about leap years).

In message
-sept
ember.org, Recliner wrote:
Oyster is far too recent for the designers to
have been trying to save microscopic amounts of memory.

Rubbish. In my job we're *still* worrying about every single byte, even
on brand new chips.

--
Clive D.W. Feather | Home:
Mobile: +44 7973 377646 | Web: http://www.davros.org
Please reply to the Reply-To address, which is:

In article id,
lid (Dr J R Stockton) wrote:

In uk.transport.london message , Sat, 2
Jan 2016 16:58:52, Richard J. posted:

You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

I think they'd learned that lesson before the millennium.

--
Colin Rosenstiel

Dr J R Stockton wrote in news:d6s+
lid:

In uk.transport.london message , Sat, 2
Jan 2016 16:58:52, Richard J. posted:


You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

The certainly was a time when saving 4 bits in a date would be worthwhile,
but by 1999 we'd got beyond that, I hope.

During a particularly wearisome Y2K fix job one of my team remarked that
we'd better allow for 5-digit years or we'd have to do the whole thing
again in 8000 years' time.

Peter

On Tue, 5 Jan 2016 11:21:09 +0000 (UTC)
Peter CS wrote:
Dr J R Stockton wrote in news:d6s+
:

In uk.transport.london message , Sat, 2
Jan 2016 16:58:52, Richard J. posted:


You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

The certainly was a time when saving 4 bits in a date would be worthwhile,
but by 1999 we'd got beyond that, I hope.

In a back end system certainly. In a smartcard with perhaps only a few KB of
RAM possibly not.

--
Spud

In article , d () wrote:

On Tue, 5 Jan 2016 11:21:09 +0000 (UTC)
Peter CS wrote:
Dr J R Stockton wrote in
. invalid:

In uk.transport.london message , Sat,
2 Jan 2016 16:58:52, Richard J. posted:


You mean there was a very similar incident 16 years ago? But what is
special about 1/1/2016 compared to 1/1/2015, 1/1/2014, etc?

It is the first year 20xx for which xx cannot be stored in four bits.

If memory space was limited in a system designed a decade ago, someone
might have chosen to use just four bits for the variable part of the
year, thinking "Well, I'll not be in this job in 2016, ha ha!".

The certainly was a time when saving 4 bits in a date would be
worthwhile, but by 1999 we'd got beyond that, I hope.

In a back end system certainly. In a smartcard with perhaps only a
few KB of RAM possibly not.

The time when dates had to be so compressed passed before the advent of
smartcards, believe me.

--
Colin Rosenstiel