[tz] POSIX epoch in the news?

Paul Eggert eggert at cs.ucla.edu
Sat Feb 13 03:28:49 UTC 2016

The bug reportedly affects only 64-bit platforms. Perhaps some part of the OS X 
boot process naively iterates from time stamps starting from 1970 up through 
"now", and treats 1969-12-31 UTC as a very large (perhaps unsigned) time stamp. 
On a 32-bit platform there are only 4 billion time stamps or so, so even a naive 
approach could work in a reasonable amount of time; a 64-bit platform, though, 
would have about 4 billion times more work to do, and users understandably don't 
want to wait that long.

If we were designing POSIX from scratch, perhaps we could let (time_t)0 denote 
the Big Bang. Then, iPhone users would need to set the date to ~13,798,000,000 
BCE to expose the bug. Nobody would have the patience to do that, since the UI 
forces them to scroll back year-by-year to the desired date. Problem solved!

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