What is this 19100 date and is it easy to fix?

greenspun.com : LUSENET : TimeBomb 2000 (Y2000) : One Thread

Captain Dave's Board and Portup.com both show a date of 19100 on the web pages. If this appeared in a financial database, how would this affect operation or would it? Could it be serious?

http://survival-center.com/

Above requires a subscription, but many here can authenticate this.

http://portup.com

-- Laurane (familyties@rttinc.com), January 01, 2000

Answers

The Debunky board is doing the same thing

-- (cavscout@fix.net), January 01, 2000.

May people are under the mistaken impression that when you add 1 to 99 you get 00. Take 99, add 1 and you get 100. Stick a 19 in front and voila: 19100

This problem will come up in general programs. It has the same effect as 00 being interpreted 1900 rather than 2000. This needs to be corrected in the same way that any other y2k problem is fixed... Change the line of code that causes the problem.

-- Mark (mpmayer@powerway.com), January 01, 2000.


Laurane,

This could never appear in any industrial strngth database, Not to worry. Remeber, anyone can design a wepage. Little date glitches on webpages are a far cry from a financial institutions software control policy. Plus Id imagine the owners of this page werent forced by the fed to perform Y2k testing on there pages, Financial instiutions were. This type of bug would have been shaken out instantly in the unlikely event it had ever crept in.

Hope this puts your mind at ease

Nyc

-- nyc (nycnyc@hotmail.com), January 01, 2000.


Thank god we have such experts on call to offer their bits of wisdom in a lurch. NOT!

First of all, Mark. What happens to the 99 depends on the number of bytes assigned to the numeric variable, it's type -- integer, floating point etc., and the action of the compiler and run-time environment.

NYC. Light weight programmers (and especially managers) can make lightweight programming errors on important, heavyweight database systems.

Pete

-- Peter Starr (startrak@northcoast.com), January 01, 2000.


Computer programmers were wrong!

greenspun.com : LUSENET : TimeBomb 2000 (Y2000) : One Thread

The Computer programmers told us that on January 1st the computer date would go back to 1900 and that would confuse the computers and cause the systems to crash. They were wrong.

In Russia where they did not do any repairs, electricity stayed up. Why?.... Simple. Yesterday the date was 1999. The computer thinks today is 19100. What is the number that comes after 99? It is 100. Next year the computer date will be 19101. We may see that date on statements from businesses, but who cares? We know that is means 2000.

I checked several websites and they all show the date as 19100. The programmers were wrong and I'm glad! Now we can go on with life as we were acustomed to. YIPPEEEEEEE!!!

HAPPY NEW YEAR "19100" to all!

-- Freddie (freddie@thefreeloader.com), January 01, 2000

Answers

Happy 19100 to you my friend! And to all!

The first 19099 have certainly been a blast. Looking forward to the next 20000 years!

-- Gordon (g_gecko_69@hotmail.com), January 01, 2000.

Huh?

This logic makes even LL look brilliant....

-- (cavscout@fix.net), January 01, 2000.

Hey Gordo-

Don't you wish you could meet some of these folks in person?

-- (cavscout@fix.net), January 01, 2000.

WOW. As a programmer for 35 years, your logic really shocks me. I sure hope none of those systems use a standard date format such as yymmdd downstream. Because this little 'error' will cause a date truncation!

-- bill dangelo (bdangelo1@home.com), January 01, 2000.

There will be problems later

-- Moore dinty Moore (dac@ccrtc.com), January 01, 2000.

Freddie,

It was the _journalists_ who kept hammering the narrow "back to 1900" theme, not the programmers. All the articles you read that mentioned only that "1900" effect were written by journalists, not programmers.

Programmers knew that the Y2k effects would be more varied than that, including the "19100" which was widely foreseen years ago (among programmers) as the result of misusing a certain function call. But the average journalist would not have understood why this problem would occur, so did not write about it.

-- No Spam Please (nos_pam_please@hotmail.com), January 01, 2000.

Just thinking about the dates being truncated. Thats why some systems have been showing dates like 1910 (the extra 0 in 100 has been clipped.)

-- Jim Bob (vibratomachina@aol.com), January 01, 2000.

What "computer programmers" told you that? It is one possible scenario--treating a 2-digit year as a simple contraction and prefixing it with "19" to form a 4-digit date instead of following a windowing rule.

In my work this last year (I have worked as a programmer for 21 years, and have been programming for 32), which involved a small amount of Y2K repair & testing work, there were no 1999->1900 problems at all. With one exception, they all involved the 99->100 or 1999->19100 error. (The exception was once piece of code that treated the two-digit year 00 as "no year entered".)

A common way of representing the date and time in the Unix (C/C++) world is via a "struct tm". This structure stores the year reduced by 1900. 1999 is represented as "99", and 2000 is represented as "100". Well, guess what happens when tens of thousands of programmers decide to save themselves several keystrokes of typing effort by treating the value as if it were really a 2-digit year.

The "struct tm" representation found its way to other platforms via the C programming language. It also found its way into to Perl (used widely for web server programming and just about anything else imaginable). Now it's all over the place, and you'll probably be viewing the fruits of those "keystroke savings" for quite some time to come.

The other part of this story is that "struct tm", at least in its original C incarnation, is a decode of a "time_t" value, which represents the number of seconds since January 1, 1970 as a 32-bit number. It runs out of capacity on January 18, 2038 at 19:14:07. Start making your plans now...

-- Ralph Scowden (res@pobox.com), January 01, 2000.

Not to worry. 2038---have enough pinto beans to last. Gee, what a thought, 93 years old and still eating pinto beans. I'm just a little goofy with delight that we have electricity today. Pam

-- Pamela (jpjgood@penn.com), January 01, 2000.

If you want to get a great picture, is it sufficient to have a great camera? My personal definition of photography is "the recording of light rays." It is therefore difficult to take a decent picture if you have not chosen the lighting carefully. ... (more)



-- ... (...@...com), January 01, 2000.



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