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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c++,comp.lang.c
Subject: Re: "C++: Size Matters in Platform Compatibility"
Date: Sun, 18 Aug 2019 14:51:32 -0700
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Keith Thompson <kst-u@mib.org> writes:
> Geoff <geoff@invalid.invalid> writes:
>> On Sun, 18 Aug 2019 12:32:18 +0200, David Brown
>> <david.brown@hesbynett.no> wrote:
>>
>>>> The UNIX epoch-based 64-bit time is good only if you believe the sun
>>>> will only last another 2.147 billion years.
>>>
>>>292 billion years, by my counting.  By that time, any issues with 
>>>rollover will be an SEP¹.
>>
>> Where are you getting that? time_t is the number of seconds since
>> January 1, 1970, 0:00 UTC and as a 64-bit integer that's not 292
>> billion years.
>
> Yes, it is.  A signed 64-bit time_t has a maximum value of 2**63-1.
> 2**63-1 seconds is just over 292 billion years.

And I meant to mention that the C and C++ standards do not specify
that time_t represents seconds since 1970, though that is the most
common implementation.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */