Operating systems of the 1970s handling dates beyond the year 2000

John Wilson wilson at dbit.com
Mon Jan 19 11:13:54 CST 2015


On Mon, Jan 19, 2015 at 02:15:38PM +0100, Johnny Billquist wrote:
>The 10000 day limit was a problem that hit the C runtime library,
>since C programs like to, and expect code, to express time as an
>offset from the epoch, which is Jan 1, 1970.
>Of course, VMS used delta times for this, and that hit 10000 days a
>little while ago, which barfed things up. I don't remember offhand
>exactly what the solution looked like.

I don't either, but I do remember an *awesome* cover letter that DEC
sent out with the fix, assuring everyone that the libraries were now good
internally until some crazy year like 31078, but there was still formatting
code that assumed years fit in four digits so there would be Y10K bugs;
but don't worry, DEC will issue a patch to VMS at that time.

John Wilson
D Bit


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