FAQ 4.18 Does Perl have a Year 2000 or 2038 problem? Is Perl Y2K compliant?

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4.18: Does Perl have a Year 2000 or 2038 problem? Is Perl Y2K compliant?

    (contributed by brian d foy)

    Perl itself never had a Y2K problem, although that never stopped people
    from creating Y2K problems on their own. See the documentation for
    "localtime" for its proper use.

    Starting with Perl 5.11, "localtime" and "gmtime" can handle dates past
    03:14:08 January 19, 2038, when a 32-bit based time would overflow. You
    still might get a warning on a 32-bit "perl":

            % perl5.11.2 -E 'say scalar localtime( 0x9FFF_FFFFFFFF )'
            Integer overflow in hexadecimal number at -e line 1.
            Wed Nov  1 19:42:39 5576711

    On a 64-bit "perl", you can get even larger dates for those really long
    running projects:

            % perl5.11.2 -E 'say scalar gmtime( 0x9FFF_FFFFFFFF )'
            Thu Nov  2 00:42:39 5576711

    You're still out of luck if you need to keep track of decaying protons


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