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Postings from September 2000
This and other RFCs are available on the web at http://dev.perl.org/rfc/ =head1 TITLE Standardize ALL Perl platforms on UNIX epoch =head1 VERSION Maintainer: Nathan Wiger <nate@wiger.org> Date: 14 Aug 2000 Last-Modified: 12 Sep 2000 Mailing List: perl6-language-datetime@perl.org Number: 99 Version: 3 Status: Developing =head1 ABSTRACT Currently, internal time in Perl is maintained via C<time>, which is highly system-dependent. On some systems, this is relative to the UNIX epoch, while others use their own epochs (MacPerl uses 1904, for example). All versions of Perl on all platforms should maintain time both internally and externally as seconds since the UNIX epoch (00:00:00 01 Jan 1970 UTC). =head1 DESCRIPTION Time is a dicey issue. While everyone disagrees on what the "right" epoch is to use, everyone generally agrees that time synchronization across different versions of Perl is a good thing. The UNIX epoch is already a widely-established standard and seems as good as any. This has the added benefit that most users will see no change, since most users use a version of Perl which is already based on the UNIX epoch. =head1 IMPLEMENTATION A simplistic Perl 5 implementation of this can be found as Time::Unix http://www.perl.com/CPAN/authors/id/N/NW/NWIGER/Time-Unix-1.02.tar.gz The C<time> core function must be changed to return the number of seconds since the UNIX epoch on ALL platforms. Note this behavior is inconsistent with previous versions of C<time> and must be noted clearly in the documentation. In addition, a C<systime> function should be added which provides access to the native epoch/system time. For simplification, it might be best if this C<systime> function remain the basis for other library-related functions, such as C<stat>, C<lstat>, and so on, which typically rely on native system time. An alternative to C<systime>, proposed by Chaim Frenkel, is to have a C<time> object which is magical yet walks and talks like a number (much like the C<date> objects proposed in RFC 48). In the author's opinion, either method is quite suitable (in fact I tend to like Chaim's idea a lot). =head1 CHANGES Version 2: 1. Added extra implementation notes 2. Wrote a I<very> simple Perl 5 implementation Version 1 of this RFC was entitled "Maintain internal time in Modified Julian (not epoch)". =head1 REFERENCES RFC 48: Replace localtime() and gmtime() with date() and utcdate() http://www.mail-archive.com/perl6-language-datetime%40perl.org/msg00001.html http://www.mail-archive.com/perl6-language-datetime%40perl.org/msg00002.html http://www.mail-archive.com/perl6-language-datetime%40perl.org/msg00025.html