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diff --git a/contrib/perl5/README.Y2K b/contrib/perl5/README.Y2K new file mode 100644 index 0000000..378db15 --- /dev/null +++ b/contrib/perl5/README.Y2K @@ -0,0 +1,47 @@ +The following information about Perl and the year 2000 is a modified +version of the information that can be found in the Frequently Asked +Question (FAQ) documents. + +Does Perl have a year 2000 problem? Is Perl Y2K compliant? + +Short answer: No, Perl does not have a year 2000 problem. Yes, + Perl is Y2K compliant (whatever that means). The + programmers you've hired to use it, however, probably are + not. If you want perl to complain when your programmers + create programs with certain types of possible year 2000 + problems, a build option allows you to turn on warnings. + +Long answer: The question belies a true understanding of the + issue. Perl is just as Y2K compliant as your pencil + --no more, and no less. Can you use your pencil to write + a non-Y2K-compliant memo? Of course you can. Is that + the pencil's fault? Of course it isn't. + + The date and time functions supplied with perl (gmtime and + localtime) supply adequate information to determine the + year well beyond 2000 (2038 is when trouble strikes for + 32-bit machines). The year returned by these functions + when used in an array context is the year minus 1900. For + years between 1910 and 1999 this happens to be a 2-digit + decimal number. To avoid the year 2000 problem simply do + not treat the year as a 2-digit number. It isn't. + + When gmtime() and localtime() are used in scalar context + they return a timestamp string that contains a fully- + expanded year. For example, $timestamp = + gmtime(1005613200) sets $timestamp to "Tue Nov 13 01:00:00 + 2001". There's no year 2000 problem here. + + That doesn't mean that Perl can't be used to create non- + Y2K compliant programs. It can. But so can your pencil. + It's the fault of the user, not the language. At the risk + of inflaming the NRA: ``Perl doesn't break Y2K, people + do.'' See http://language.perl.com/news/y2k.html for a + longer exposition. + + If you want perl to warn you when it sees a program which + catenates a number with the string "19" -- a common + indication of a year 2000 problem -- build perl using the + Configure option "-Accflags=-DPERL_Y2KWARN". + (See the file INSTALL for more information about building + perl.) |
