Re: "C++: Size Matters in Platform Compatibility"

From	Geoff <geoff@invalid.invalid>
Newsgroups	comp.lang.c++, comp.lang.c
Subject	Re: "C++: Size Matters in Platform Compatibility"
Date	2019-08-17 12:43 -0700
Organization	A noiseless patient Spider
Message-ID	<mnkglelt8koldbugfin9q27eb3qptod8b5@4ax.com> (permalink)
References	<qj6ung$map$1@dont-email.me> <qj8u95$3if$1@dont-email.me>

Cross-posted to 2 groups.

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On Sat, 17 Aug 2019 15:08:52 +0200, David Brown
<david.brown@hesbynett.no> wrote:

[snip]

>
>If you are storing data in binary formats that need to be portable, you 
>need to define and document the format, making it independent of the 
>platform.  The author here glosses over the important bits - endianness 
>and alignment (and consequently padding), which he doesn't mention at all.
>

He does mention endianess and he declined to discuss it, saying it
needs a separate discussion. You are the second poster here to
overlook that.

[snip]

> Often the most sensible formats 
>is 64 bit Unix epoch timestamps (happily covering the big bang up to 
>well past the death of our sun).  IEEE floating point double Unix epoch 
>seconds will last longer than protons, and give you accurate fractions 
>of a second for more normal timeframes.  If these are not suitable, 
>define a format for your particular requirements.

The UNIX epoch-based 64-bit time is good only if you believe the sun
will only last another 2.147 billion years. The epoch time rolls over
in the year 2,147,485,547 on MacOS. The sun is calculated to have
another 5.4 billion years of hydrogen fuel left. 

Proton decay, so far, is only theoretical. It has never been observed.

[snip]

Thread

"C++: Size Matters in Platform Compatibility" Lynn McGuire <lynnmcguire5@gmail.com> - 2019-08-16 14:04 -0500
  Re: "C++: Size Matters in Platform Compatibility" Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-08-16 20:45 +0000
  Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-17 15:08 +0200
    Re: "C++: Size Matters in Platform Compatibility" Geoff <geoff@invalid.invalid> - 2019-08-17 12:43 -0700
      Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-18 12:32 +0200
        Re: "C++: Size Matters in Platform Compatibility" Geoff <geoff@invalid.invalid> - 2019-08-18 13:10 -0700
          Re: "C++: Size Matters in Platform Compatibility" Bart <bc@freeuk.com> - 2019-08-18 21:15 +0100
          Re: "C++: Size Matters in Platform Compatibility" Keith Thompson <kst-u@mib.org> - 2019-08-18 14:49 -0700
            Re: "C++: Size Matters in Platform Compatibility" Keith Thompson <kst-u@mib.org> - 2019-08-18 14:51 -0700
          Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-19 08:43 +0200
            Re: "C++: Size Matters in Platform Compatibility" "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-19 09:15 +0200
            Re: "C++: Size Matters in Platform Compatibility" Öö Tiib <ootiib@hot.ee> - 2019-08-19 01:07 -0700
      Re: "C++: Size Matters in Platform Compatibility" Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-21 17:14 +0200
        Re: "C++: Size Matters in Platform Compatibility" Eli the Bearded <*@eli.users.panix.com> - 2019-08-21 18:30 +0000
          Re: "C++: Size Matters in Platform Compatibility" scott@slp53.sl.home (Scott Lurndal) - 2019-08-21 19:05 +0000
          Re: "C++: Size Matters in Platform Compatibility" Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-21 21:25 +0200
          Re: "C++: Size Matters in Platform Compatibility" Keith Thompson <kst-u@mib.org> - 2019-08-21 12:28 -0700
          Re: "C++: Size Matters in Platform Compatibility" Richard Damon <Richard@Damon-Family.org> - 2019-08-22 22:58 -0400
            Re: "C++: Size Matters in Platform Compatibility" Eli the Bearded <*@eli.users.panix.com> - 2019-08-23 19:15 +0000
    Re: "C++: Size Matters in Platform Compatibility" Anton Shepelev <anton.txt@gmail.com> - 2019-08-18 15:59 +0300
      Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-18 16:32 +0200
    Re: "C++: Size Matters in Platform Compatibility" Juha Nieminen <nospam@thanks.invalid> - 2019-08-19 07:29 +0000
      Re: "C++: Size Matters in Platform Compatibility" Paavo Helde <myfirstname@osa.pri.ee> - 2019-08-19 12:20 +0300
      Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-19 11:22 +0200
        Re: "C++: Size Matters in Platform Compatibility" Richard Damon <Richard@Damon-Family.org> - 2019-08-23 14:14 -0400
          Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-24 20:56 +0200
            Re: "C++: Size Matters in Platform Compatibility" Robert Wessel <robertwessel2@yahoo.com> - 2019-08-24 23:43 -0500
              Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-25 12:11 +0200
                Re: "C++: Size Matters in Platform Compatibility" Richard Damon <Richard@Damon-Family.org> - 2019-08-25 07:33 -0700
                Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-25 20:27 +0200
                Re: "C++: Size Matters in Platform Compatibility" Robert Wessel <robertwessel2@yahoo.com> - 2019-08-25 10:22 -0500
    Re: "C++: Size Matters in Platform Compatibility" Lynn McGuire <lynnmcguire5@gmail.com> - 2019-08-19 15:05 -0500
      Re: "C++: Size Matters in Platform Compatibility" scott@slp53.sl.home (Scott Lurndal) - 2019-08-19 20:17 +0000
        Re: "C++: Size Matters in Platform Compatibility" David Brown <david.brown@hesbynett.no> - 2019-08-20 08:21 +0200
          Re: "C++: Size Matters in Platform Compatibility" Lynn McGuire <lynnmcguire5@gmail.com> - 2019-08-20 14:38 -0500
      Re: "C++: Size Matters in Platform Compatibility" James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-21 09:15 -0400
  Re: "C++: Size Matters in Platform Compatibility" Anton Shepelev <anton.txt@gmail.com> - 2019-08-18 15:20 +0300
    Re: "C++: Size Matters in Platform Compatibility" Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-08-18 14:50 +0100

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