5 ms·

Fighting a 30-year-old software bug

78 points by levosmetalo 13y ago

ttflee 13y ago
Sometimes I feel guilty for not insisting to use 64-bit time stamp for company's products. Hope anyone keeping those gadgets long enough to hit year 2038 would get sufficient fortune.
deleted 13y ago
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apaprocki 13y ago
Related anecdote: Interestingly enough, Excel doesn't support dates prior to the "Excel epoch". I had some genealogical spreadsheets that I had to move to Google Docs from Excel because Docs supports arbitrary years and Excel treats anything prior than 1900 as strings instead of dates, losing the ability to perform date/time operations.
- ttflee 13y ago
  I guess those dates must be treated with greater caution, as the history and calendar used to be complicated(, not as smooth as UTC time). http://www.quirksmode.org/blog/archives/2009/04/making_time_saf.html http://www.quirksmode.org/blog/archives/2009/04/making_time_...
  - apaprocki 13y ago
    Sure, but I'm mainly talking about using a spreadsheet just as a spreadsheet. If you enter a bunch of mixed pre-/post-1900 dates into a column and then change the formatting to display as "DD-Mon-YYYY" everything will change except the pre- dates. There isn't really anything complicated needed to make that work, implementation-wise.
xntrk 13y ago
How old is the bug? The url says 20 the link and header both say 30.
- agrona 13y ago
  FTA >Er, an earlier version of this said the software bug was 20 years old. It's 30! Thanks, Sidhekin
- eCa 13y ago
  Lotus 1-2-3, the cause of the bug/feature, was released in 1983 [1]. [1] http://en.wikipedia.org/wiki/Lotus_1-2-3 http://en.wikipedia.org/wiki/Lotus_1-2-3
- Ovid 13y ago
  Yeah, I'm the author of that post and I elected not to change the link after I changed the title. I love the irony of me originally making a date math error in the title when the bug was about date math :)
curveship 13y ago
Given Excel's popularity in the business world, I wonder if an exploit of some sort could be built into scheduling a transaction for February 29th, 1900. The date exists in Excel, but not the real world.
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finnh 13y ago
Classic example of why greenfield development is much more pleasant than dealing with legacy systems. Of course, you have to do your new dev well to prevent it from becoming a legacy system that you have to fight with... But I do think the world of development is just soooo much better now that it was 10 or 20 years ago. We, as a profession, have much to be thankful for.
patmcguire 13y ago
My first thought was, "I remember this. Blame Joel Spolsky:" http://www.joelonsoftware.com/items/2006/06/16.html http://www.joelonsoftware.com/items/2006/06/16.html (well maybe not blame, it's a tradeoff.) But he mentions it at the end.
- oaktowner 13y ago
  Nice call! I was coming in to post that link, but I see you beat me to the punch.

78 points by levosmetalo 13y ago

Sometimes I feel guilty for not insisting to use 64-bit time stamp for company's products. Hope anyone keeping those gadgets long enough to hit year 2038 would get sufficient fortune.

deleted 13y ago

[deleted]

apaprocki 13y ago

Related anecdote: Interestingly enough, Excel doesn't support dates prior to the "Excel epoch". I had some genealogical spreadsheets that I had to move to Google Docs from Excel because Docs supports arbitrary years and Excel treats anything prior than 1900 as strings instead of dates, losing the ability to perform date/time operations.

ttflee 13y ago
I guess those dates must be treated with greater caution, as the history and calendar used to be complicated(, not as smooth as UTC time). http://www.quirksmode.org/blog/archives/2009/04/making_time_saf.html http://www.quirksmode.org/blog/archives/2009/04/making_time_...
- apaprocki 13y ago
  Sure, but I'm mainly talking about using a spreadsheet just as a spreadsheet. If you enter a bunch of mixed pre-/post-1900 dates into a column and then change the formatting to display as "DD-Mon-YYYY" everything will change except the pre- dates. There isn't really anything complicated needed to make that work, implementation-wise.

xntrk 13y ago

How old is the bug? The url says 20 the link and header both say 30.

agrona 13y ago
FTA >Er, an earlier version of this said the software bug was 20 years old. It's 30! Thanks, Sidhekin
eCa 13y ago
Lotus 1-2-3, the cause of the bug/feature, was released in 1983 [1]. [1] http://en.wikipedia.org/wiki/Lotus_1-2-3 http://en.wikipedia.org/wiki/Lotus_1-2-3
Ovid 13y ago
Yeah, I'm the author of that post and I elected not to change the link after I changed the title. I love the irony of me originally making a date math error in the title when the bug was about date math :)

curveship 13y ago

Given Excel's popularity in the business world, I wonder if an exploit of some sort could be built into scheduling a transaction for February 29th, 1900. The date exists in Excel, but not the real world.

deleted 13y ago

[deleted]

finnh 13y ago

Classic example of why greenfield development is much more pleasant than dealing with legacy systems. Of course, you have to do your new dev well to prevent it from becoming a legacy system that you have to fight with... But I do think the world of development is just soooo much better now that it was 10 or 20 years ago. We, as a profession, have much to be thankful for.

patmcguire 13y ago

My first thought was, "I remember this. Blame Joel Spolsky:" http://www.joelonsoftware.com/items/2006/06/16.html http://www.joelonsoftware.com/items/2006/06/16.html (well maybe not blame, it's a tradeoff.) But he mentions it at the end.

oaktowner 13y ago
Nice call! I was coming in to post that link, but I see you beat me to the punch.