negative time_t values

Moderator, John Quarterman std-unix at ut-sally.UUCP
Sat Aug 30 04:51:09 AEST 1986


From: elsie!ado at seismo.UUCP 
Date: Mon, 25 Aug 86 18:35:05 EDT
Subject: negative time_t values

While it's true that no UNIX files date back to before January 1, 1970,
there *are* uses for times before that epoch:  in personnel data bases where
birth dates are recorded; in data bases recording astronomical events;
in stock market price data bases (as used by chartist fanatics); and elsewhere.
(And what of all those old 7094 executables that are being used on IBM machines
running UNIX or a cousin?  :-))

I see more use in the short run for being able to record times between
1901 and 1970 that I see for being able to record times after 2038.
And if we do make it into the twenty-first century, I imagine we'll be working
on machines with 256-bit registers where time_t will have a type that allows
it to represent times into the very distant future; if it's defined properly,
time_t variables will also be able to represent times into the very distant
past.

In summary:  I'd recommend retaining the ability for time_t variables to
represent times before 1970.
--
UNIX is an AT&T registered trademark.
Time is a Time/Life Incorporated trademark.
IBM is an IBM trademark.
--
	UUCP: ..decvax!seismo!elsie!ado   ARPA: elsie!ado at seismo.ARPA
	DEC, VAX, Elsie & Ado are Digital, Borden & Ampex trademarks.


Volume-Number: Volume 6, Number 41



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