=head1 NAME Time::OlsonTZ::Data - Olson timezone data =head1 SYNOPSIS use Time::OlsonTZ::Data qw( olson_version olson_code_version olson_data_version ); $version = olson_version; $version = olson_code_version; $version = olson_data_version; use Time::OlsonTZ::Data qw( olson_canonical_names olson_link_names olson_all_names olson_links olson_country_selection ); $names = olson_canonical_names; $names = olson_link_names; $names = olson_all_names; $links = olson_links; $countries = olson_country_selection; use Time::OlsonTZ::Data qw(olson_tzfile); $filename = olson_tzfile("America/New_York"); =head1 DESCRIPTION This module encapsulates the Olson timezone database, providing binary tzfiles and ancillary data. Each version of this module encapsulates a particular version of the timezone database. It is intended to be regularly updated, as the timezone database changes. =cut package Time::OlsonTZ::Data; { use 5.006; } use warnings; use strict; our $VERSION = "0.201205"; use parent "Exporter"; our @EXPORT_OK = qw( olson_version olson_code_version olson_data_version olson_canonical_names olson_link_names olson_all_names olson_links olson_country_selection olson_tzfile ); my($datavol, $datadir); sub _data_file($) { my($upath) = @_; unless(defined $datadir) { require File::Spec; ($datavol, $datadir, undef) = File::Spec->splitpath($INC{"Time/OlsonTZ/Data.pm"}); } my @nameparts = split(/\//, $upath); my $filename = pop(@nameparts); return File::Spec->catpath($datavol, File::Spec->catdir($datadir, "Data", @nameparts), $filename); } =head1 FUNCTIONS =head2 Basic information =over =item olson_version Returns the version number of the database that this module encapsulates. Version numbers for the Olson database currently consist of a year number and a lowercase letter, such as "C<2010k>"; they are not guaranteed to retain this format in the future. =cut use constant olson_version => "2012e"; =item olson_code_version Returns the version number of the code part of the database that this module encapsulates. =cut use constant olson_code_version => "2012e"; =item olson_data_version Returns the version number of the data part of the database that this module encapsulates. =cut use constant olson_data_version => "2012e"; =back =head2 Zone metadata =over =item olson_canonical_names Returns the set of timezone names that this version of the database defines as canonical. These are the timezone names that are directly associated with a set of observance data. The return value is a reference to a hash, in which the keys are the canonical timezone names and the values are all C<undef>. =cut my $cn = q(+{ map { ($_ => undef) } qw( Africa/Abidjan Africa/Accra Africa/Addis_Ababa Africa/Algiers Africa/Asmara Africa/Bamako Africa/Bangui Africa/Banjul Africa/Bissau Africa/Blantyre Africa/Brazzaville Africa/Bujumbura Africa/Cairo Africa/Casablanca Africa/Ceuta Africa/Conakry Africa/Dakar Africa/Dar_es_Salaam Africa/Djibouti Africa/Douala Africa/El_Aaiun Africa/Freetown Africa/Gaborone Africa/Harare Africa/Johannesburg Africa/Juba Africa/Kampala Africa/Khartoum Africa/Kigali Africa/Kinshasa Africa/Lagos Africa/Libreville Africa/Lome Africa/Luanda Africa/Lubumbashi Africa/Lusaka Africa/Malabo Africa/Maputo Africa/Maseru Africa/Mbabane Africa/Mogadishu Africa/Monrovia Africa/Nairobi Africa/Ndjamena Africa/Niamey Africa/Nouakchott Africa/Ouagadougou Africa/Porto-Novo Africa/Sao_Tome Africa/Tripoli Africa/Tunis Africa/Windhoek America/Adak America/Anchorage America/Anguilla America/Antigua America/Araguaina America/Argentina/Buenos_Aires America/Argentina/Catamarca America/Argentina/Cordoba America/Argentina/Jujuy America/Argentina/La_Rioja America/Argentina/Mendoza America/Argentina/Rio_Gallegos America/Argentina/Salta America/Argentina/San_Juan America/Argentina/San_Luis America/Argentina/Tucuman America/Argentina/Ushuaia America/Aruba America/Asuncion America/Atikokan America/Bahia America/Bahia_Banderas America/Barbados America/Belem America/Belize America/Blanc-Sablon America/Boa_Vista America/Bogota America/Boise America/Cambridge_Bay America/Campo_Grande America/Cancun America/Caracas America/Cayenne America/Cayman America/Chicago America/Chihuahua America/Costa_Rica America/Creston America/Cuiaba America/Curacao America/Danmarkshavn America/Dawson America/Dawson_Creek America/Denver America/Detroit America/Dominica America/Edmonton America/Eirunepe America/El_Salvador America/Fortaleza America/Glace_Bay America/Godthab America/Goose_Bay America/Grand_Turk America/Grenada America/Guadeloupe America/Guatemala America/Guayaquil America/Guyana America/Halifax America/Havana America/Hermosillo America/Indiana/Indianapolis America/Indiana/Knox America/Indiana/Marengo America/Indiana/Petersburg America/Indiana/Tell_City America/Indiana/Vevay America/Indiana/Vincennes America/Indiana/Winamac America/Inuvik America/Iqaluit America/Jamaica America/Juneau America/Kentucky/Louisville America/Kentucky/Monticello America/La_Paz America/Lima America/Los_Angeles America/Maceio America/Managua America/Manaus America/Martinique America/Matamoros America/Mazatlan America/Menominee America/Merida America/Metlakatla America/Mexico_City America/Miquelon America/Moncton America/Monterrey America/Montevideo America/Montreal America/Montserrat America/Nassau America/New_York America/Nipigon America/Nome America/Noronha America/North_Dakota/Beulah America/North_Dakota/Center America/North_Dakota/New_Salem America/Ojinaga America/Panama America/Pangnirtung America/Paramaribo America/Phoenix America/Port-au-Prince America/Port_of_Spain America/Porto_Velho America/Puerto_Rico America/Rainy_River America/Rankin_Inlet America/Recife America/Regina America/Resolute America/Rio_Branco America/Santa_Isabel America/Santarem America/Santiago America/Santo_Domingo America/Sao_Paulo America/Scoresbysund America/Sitka America/St_Johns America/St_Kitts America/St_Lucia America/St_Thomas America/St_Vincent America/Swift_Current America/Tegucigalpa America/Thule America/Thunder_Bay America/Tijuana America/Toronto America/Tortola America/Vancouver America/Whitehorse America/Winnipeg America/Yakutat America/Yellowknife Antarctica/Casey Antarctica/Davis Antarctica/DumontDUrville Antarctica/Macquarie Antarctica/Mawson Antarctica/McMurdo Antarctica/Palmer Antarctica/Rothera Antarctica/Syowa Antarctica/Vostok Asia/Aden Asia/Almaty Asia/Amman Asia/Anadyr Asia/Aqtau Asia/Aqtobe Asia/Ashgabat Asia/Baghdad Asia/Bahrain Asia/Baku Asia/Bangkok Asia/Beirut Asia/Bishkek Asia/Brunei Asia/Choibalsan Asia/Chongqing Asia/Colombo Asia/Damascus Asia/Dhaka Asia/Dili Asia/Dubai Asia/Dushanbe Asia/Gaza Asia/Harbin Asia/Hebron Asia/Ho_Chi_Minh Asia/Hong_Kong Asia/Hovd Asia/Irkutsk Asia/Jakarta Asia/Jayapura Asia/Jerusalem Asia/Kabul Asia/Kamchatka Asia/Karachi Asia/Kashgar Asia/Kathmandu Asia/Kolkata Asia/Krasnoyarsk Asia/Kuala_Lumpur Asia/Kuching Asia/Kuwait Asia/Macau Asia/Magadan Asia/Makassar Asia/Manila Asia/Muscat Asia/Nicosia Asia/Novokuznetsk Asia/Novosibirsk Asia/Omsk Asia/Oral Asia/Phnom_Penh Asia/Pontianak Asia/Pyongyang Asia/Qatar Asia/Qyzylorda Asia/Rangoon Asia/Riyadh Asia/Riyadh87 Asia/Riyadh88 Asia/Riyadh89 Asia/Sakhalin Asia/Samarkand Asia/Seoul Asia/Shanghai Asia/Singapore Asia/Taipei Asia/Tashkent Asia/Tbilisi Asia/Tehran Asia/Thimphu Asia/Tokyo Asia/Ulaanbaatar Asia/Urumqi Asia/Vientiane Asia/Vladivostok Asia/Yakutsk Asia/Yekaterinburg Asia/Yerevan Atlantic/Azores Atlantic/Bermuda Atlantic/Canary Atlantic/Cape_Verde Atlantic/Faroe Atlantic/Madeira Atlantic/Reykjavik Atlantic/South_Georgia Atlantic/St_Helena Atlantic/Stanley Australia/Adelaide Australia/Brisbane Australia/Broken_Hill Australia/Currie Australia/Darwin Australia/Eucla Australia/Hobart Australia/Lindeman Australia/Lord_Howe Australia/Melbourne Australia/Perth Australia/Sydney CET CST6CDT EET EST EST5EDT Etc/GMT Etc/GMT+1 Etc/GMT+10 Etc/GMT+11 Etc/GMT+12 Etc/GMT+2 Etc/GMT+3 Etc/GMT+4 Etc/GMT+5 Etc/GMT+6 Etc/GMT+7 Etc/GMT+8 Etc/GMT+9 Etc/GMT-1 Etc/GMT-10 Etc/GMT-11 Etc/GMT-12 Etc/GMT-13 Etc/GMT-14 Etc/GMT-2 Etc/GMT-3 Etc/GMT-4 Etc/GMT-5 Etc/GMT-6 Etc/GMT-7 Etc/GMT-8 Etc/GMT-9 Etc/UCT Etc/UTC Europe/Amsterdam Europe/Andorra Europe/Athens Europe/Belgrade Europe/Berlin Europe/Brussels Europe/Bucharest Europe/Budapest Europe/Chisinau Europe/Copenhagen Europe/Dublin Europe/Gibraltar Europe/Helsinki Europe/Istanbul Europe/Kaliningrad Europe/Kiev Europe/Lisbon Europe/London Europe/Luxembourg Europe/Madrid Europe/Malta Europe/Minsk Europe/Monaco Europe/Moscow Europe/Oslo Europe/Paris Europe/Prague Europe/Riga Europe/Rome Europe/Samara Europe/Simferopol Europe/Sofia Europe/Stockholm Europe/Tallinn Europe/Tirane Europe/Uzhgorod Europe/Vaduz Europe/Vienna Europe/Vilnius Europe/Volgograd Europe/Warsaw Europe/Zaporozhye Europe/Zurich Factory HST Indian/Antananarivo Indian/Chagos Indian/Christmas Indian/Cocos Indian/Comoro Indian/Kerguelen Indian/Mahe Indian/Maldives Indian/Mauritius Indian/Mayotte Indian/Reunion MET MST MST7MDT PST8PDT Pacific/Apia Pacific/Auckland Pacific/Chatham Pacific/Chuuk Pacific/Easter Pacific/Efate Pacific/Enderbury Pacific/Fakaofo Pacific/Fiji Pacific/Funafuti Pacific/Galapagos Pacific/Gambier Pacific/Guadalcanal Pacific/Guam Pacific/Honolulu Pacific/Johnston Pacific/Kiritimati Pacific/Kosrae Pacific/Kwajalein Pacific/Majuro Pacific/Marquesas Pacific/Midway Pacific/Nauru Pacific/Niue Pacific/Norfolk Pacific/Noumea Pacific/Pago_Pago Pacific/Palau Pacific/Pitcairn Pacific/Pohnpei Pacific/Port_Moresby Pacific/Rarotonga Pacific/Saipan Pacific/Tahiti Pacific/Tarawa Pacific/Tongatapu Pacific/Wake Pacific/Wallis WET ) }); sub olson_canonical_names() { $cn = eval($cn) || die $@ if ref($cn) eq ""; return $cn; } =item olson_link_names Returns the set of timezone names that this version of the database defines as links. These are the timezone names that are aliases for other names. The return value is a reference to a hash, in which the keys are the link timezone names and the values are all C<undef>. =cut sub olson_links(); my $ln; sub olson_link_names() { return $ln ||= { map { ($_ => undef) } keys %{olson_links()} }; } =item olson_all_names Returns the set of timezone names that this version of the database defines. These are the L</olson_canonical_names> and the L</olson_link_names>. The return value is a reference to a hash, in which the keys are the timezone names and the values are all C<undef>. =cut my $an; sub olson_all_names() { return $an ||= { %{olson_canonical_names()}, %{olson_link_names()}, }; } =item olson_links Returns details of the timezone name links in this version of the database. Each link defines one timezone name as an alias for some other timezone name. The return value is a reference to a hash, in which the keys are the aliases and each value is the canonical name of the timezone to which that alias refers. All such canonical names can be found in the L</olson_canonical_names> hash. =cut my $li = q(+{ "Africa/Asmera" => "Africa/Asmara", "Africa/Timbuktu" => "Africa/Bamako", "America/Argentina/ComodRivadavia" => "America/Argentina/Catamarca", "America/Atka" => "America/Adak", "America/Buenos_Aires" => "America/Argentina/Buenos_Aires", "America/Catamarca" => "America/Argentina/Catamarca", "America/Coral_Harbour" => "America/Atikokan", "America/Cordoba" => "America/Argentina/Cordoba", "America/Ensenada" => "America/Tijuana", "America/Fort_Wayne" => "America/Indiana/Indianapolis", "America/Indianapolis" => "America/Indiana/Indianapolis", "America/Jujuy" => "America/Argentina/Jujuy", "America/Knox_IN" => "America/Indiana/Knox", "America/Kralendijk" => "America/Curacao", "America/Louisville" => "America/Kentucky/Louisville", "America/Lower_Princes" => "America/Curacao", "America/Marigot" => "America/Guadeloupe", "America/Mendoza" => "America/Argentina/Mendoza", "America/Porto_Acre" => "America/Rio_Branco", "America/Rosario" => "America/Argentina/Cordoba", "America/Shiprock" => "America/Denver", "America/St_Barthelemy" => "America/Guadeloupe", "America/Virgin" => "America/St_Thomas", "Antarctica/South_Pole" => "Antarctica/McMurdo", "Arctic/Longyearbyen" => "Europe/Oslo", "Asia/Ashkhabad" => "Asia/Ashgabat", "Asia/Calcutta" => "Asia/Kolkata", "Asia/Chungking" => "Asia/Chongqing", "Asia/Dacca" => "Asia/Dhaka", "Asia/Istanbul" => "Europe/Istanbul", "Asia/Katmandu" => "Asia/Kathmandu", "Asia/Macao" => "Asia/Macau", "Asia/Saigon" => "Asia/Ho_Chi_Minh", "Asia/Tel_Aviv" => "Asia/Jerusalem", "Asia/Thimbu" => "Asia/Thimphu", "Asia/Ujung_Pandang" => "Asia/Makassar", "Asia/Ulan_Bator" => "Asia/Ulaanbaatar", "Atlantic/Faeroe" => "Atlantic/Faroe", "Atlantic/Jan_Mayen" => "Europe/Oslo", "Australia/ACT" => "Australia/Sydney", "Australia/Canberra" => "Australia/Sydney", "Australia/LHI" => "Australia/Lord_Howe", "Australia/NSW" => "Australia/Sydney", "Australia/North" => "Australia/Darwin", "Australia/Queensland" => "Australia/Brisbane", "Australia/South" => "Australia/Adelaide", "Australia/Tasmania" => "Australia/Hobart", "Australia/Victoria" => "Australia/Melbourne", "Australia/West" => "Australia/Perth", "Australia/Yancowinna" => "Australia/Broken_Hill", "Brazil/Acre" => "America/Rio_Branco", "Brazil/DeNoronha" => "America/Noronha", "Brazil/East" => "America/Sao_Paulo", "Brazil/West" => "America/Manaus", "Canada/Atlantic" => "America/Halifax", "Canada/Central" => "America/Winnipeg", "Canada/East-Saskatchewan" => "America/Regina", "Canada/Eastern" => "America/Toronto", "Canada/Mountain" => "America/Edmonton", "Canada/Newfoundland" => "America/St_Johns", "Canada/Pacific" => "America/Vancouver", "Canada/Saskatchewan" => "America/Regina", "Canada/Yukon" => "America/Whitehorse", "Chile/Continental" => "America/Santiago", "Chile/EasterIsland" => "Pacific/Easter", Cuba => "America/Havana", Egypt => "Africa/Cairo", Eire => "Europe/Dublin", "Etc/GMT+0" => "Etc/GMT", "Etc/GMT-0" => "Etc/GMT", "Etc/GMT0" => "Etc/GMT", "Etc/Greenwich" => "Etc/GMT", "Etc/Universal" => "Etc/UTC", "Etc/Zulu" => "Etc/UTC", "Europe/Belfast" => "Europe/London", "Europe/Bratislava" => "Europe/Prague", "Europe/Guernsey" => "Europe/London", "Europe/Isle_of_Man" => "Europe/London", "Europe/Jersey" => "Europe/London", "Europe/Ljubljana" => "Europe/Belgrade", "Europe/Mariehamn" => "Europe/Helsinki", "Europe/Nicosia" => "Asia/Nicosia", "Europe/Podgorica" => "Europe/Belgrade", "Europe/San_Marino" => "Europe/Rome", "Europe/Sarajevo" => "Europe/Belgrade", "Europe/Skopje" => "Europe/Belgrade", "Europe/Tiraspol" => "Europe/Chisinau", "Europe/Vatican" => "Europe/Rome", "Europe/Zagreb" => "Europe/Belgrade", GB => "Europe/London", "GB-Eire" => "Europe/London", GMT => "Etc/GMT", "GMT+0" => "Etc/GMT", "GMT-0" => "Etc/GMT", GMT0 => "Etc/GMT", Greenwich => "Etc/GMT", Hongkong => "Asia/Hong_Kong", Iceland => "Atlantic/Reykjavik", Iran => "Asia/Tehran", Israel => "Asia/Jerusalem", Jamaica => "America/Jamaica", Japan => "Asia/Tokyo", Kwajalein => "Pacific/Kwajalein", Libya => "Africa/Tripoli", "Mexico/BajaNorte" => "America/Tijuana", "Mexico/BajaSur" => "America/Mazatlan", "Mexico/General" => "America/Mexico_City", "Mideast/Riyadh87" => "Asia/Riyadh87", "Mideast/Riyadh88" => "Asia/Riyadh88", "Mideast/Riyadh89" => "Asia/Riyadh89", NZ => "Pacific/Auckland", "NZ-CHAT" => "Pacific/Chatham", Navajo => "America/Denver", PRC => "Asia/Shanghai", "Pacific/Ponape" => "Pacific/Pohnpei", "Pacific/Samoa" => "Pacific/Pago_Pago", "Pacific/Truk" => "Pacific/Chuuk", "Pacific/Yap" => "Pacific/Chuuk", Poland => "Europe/Warsaw", Portugal => "Europe/Lisbon", ROC => "Asia/Taipei", ROK => "Asia/Seoul", Singapore => "Asia/Singapore", Turkey => "Europe/Istanbul", UCT => "Etc/UCT", "US/Alaska" => "America/Anchorage", "US/Aleutian" => "America/Adak", "US/Arizona" => "America/Phoenix", "US/Central" => "America/Chicago", "US/East-Indiana" => "America/Indiana/Indianapolis", "US/Eastern" => "America/New_York", "US/Hawaii" => "Pacific/Honolulu", "US/Indiana-Starke" => "America/Indiana/Knox", "US/Michigan" => "America/Detroit", "US/Mountain" => "America/Denver", "US/Pacific" => "America/Los_Angeles", "US/Pacific-New" => "America/Los_Angeles", "US/Samoa" => "Pacific/Pago_Pago", UTC => "Etc/UTC", Universal => "Etc/UTC", "W-SU" => "Europe/Moscow", Zulu => "Etc/UTC", }); sub olson_links() { $li = eval($li) || die $@ if ref($li) eq ""; return $li; } =item olson_country_selection Returns information about how timezones relate to countries, intended to aid humans in selecting a geographical timezone. This information is derived from the C<zone.tab> and C<iso3166.tab> files in the database source. The return value is a reference to a hash, keyed by (ISO 3166 alpha-2 uppercase) country code. The value for each country is a hash containing these values: =over =item B<alpha2_code> The ISO 3166 alpha-2 uppercase country code. =item B<olson_name> An English name for the country, possibly in a modified form, optimised to help humans find the right entry in alphabetical lists. This is not necessarily identical to the country's standard short or long name. (For other forms of the name, consult a database of countries, keying by the country code.) =item B<regions> Information about the regions of the country that use distinct timezones. This is a hash, keyed by English description of the region. The description is empty if there is only one region. The value for each region is a hash containing these values: =over =item B<olson_description> Brief English description of the region, used to distinguish between the regions of a single country. Empty string if the country has only one region for timezone purposes. (This is the same string used as the key in the B<regions> hash.) =item B<timezone_name> Name of the Olson timezone used in this region. The named timezone is guaranteed to exist in the database, but not necessarily as a canonical name (it may be a link). Typically, where there are aliases or identical canonical zones, a name is chosen that refers to a location in the country of interest. =item B<location_coords> Geographical coordinates of some point within the location referred to in the timezone name. This is a latitude and longitude, in ISO 6709 format. =back =back This data structure is intended to help a human select the appropriate timezone based on political geography, specifically working from a selection of country. It is of essentially no use for any other purpose. It is not strictly guaranteed that every geographical timezone in the database is listed somewhere in this structure, so it is of limited use in providing information about an already-selected timezone. It does not include non-geographic timezones at all. It also does not claim to be a comprehensive list of countries, and does not make any claims regarding the political status of any entity listed: the "country" classification is loose, and used only for identification purposes. =cut my $cs; sub olson_country_selection() { return $cs ||= do { my $fn = _data_file("country_selection.tzp"); $@ = ""; do($fn) || die($@ eq "" ? "$fn: $!" : $@); } } =back =head2 Zone data =over =item olson_tzfile(NAME) Returns the pathname of the binary tzfile (in L<tzfile(5)> format) describing the timezone named I<NAME> in the Olson database. C<die>s if the name does not exist in this version of the database. The tzfile is of at least version 2 of the format, and so does not suffer a Y2038 (32-bit time_t) problem. =cut sub olson_tzfile($) { my($tzname) = @_; $tzname = olson_links()->{$tzname} if exists olson_links()->{$tzname}; unless(exists olson_canonical_names()->{$tzname}) { require Carp; Carp::croak("no such timezone `$tzname' ". "in the Olson @{[olson_version]} database"); } return _data_file($tzname.".tz"); } =back =head1 BUGS The Olson timezone database probably contains errors in the older historical data. These will be corrected, as they are discovered, in future versions of the database. Because legislatures commonly change civil timezone rules, in unpredictable ways and often with little advance notice, the current timezone data is liable to get out of date quite quickly. The Olson timezone database is frequently updated to keep it accurate for current dates. Frequently updating installations of this module from CPAN should keep it similarly accurate. For the same reason, the future data in the database is liable to be very inaccurate. The database includes, for each timezone, the current best guess regarding its future behaviour, usually consisting of the current rules being left unchanged indefinitely. (In most cases it is unlikely that the rules will actually never be changed, but the current rules still constitute the best guess available of future behaviour.) Because this module is intended to be frequently updated, long-running programs (such as clock displays) will experience the module being updated while in use. This can happen with any module, but is of particular interest with this one. The behaviour in this situation is not guaranteed, but here is a guide to current behaviour. The running module code is of course not influenced by the C<.pm> file changing. The ancillary data is all currently stored in the module code, and so will be equally unaffected. Tzfiles pointed to by the module, however, will change visibly. Newly reading a tzfile is liable to see a newer version of the zone's data than the module's metadata suggests. A tzfile could also theoretically disappear, if a zone's canonical name changes (so the former canonical name becomes a link). To avoid weirdness, it is recommended to read in all required tzfiles near the start of a program's run, so that it doesn't matter if the files subsequently change due to an update. =head1 SEE ALSO L<App::olson>, L<DateTime::TimeZone::Olson>, L<DateTime::TimeZone::Tzfile>, L<Time::OlsonTZ::Download>, L<tzfile(5)> =head1 AUTHOR The Olson timezone database was compiled by Arthur David Olson, Paul Eggert, and many others. It is maintained by the denizens of the mailing list <tz@iana.org> (formerly <tz@elsie.nci.nih.gov>). The C<Time::OlsonTZ::Data> Perl module wrapper for the database was developed by Andrew Main (Zefram) <zefram@fysh.org>. =head1 COPYRIGHT The Olson timezone database is is the public domain. The C<Time::OlsonTZ::Data> Perl module wrapper for the database is Copyright (C) 2010, 2011, 2012 Andrew Main (Zefram) <zefram@fysh.org>. =head1 LICENSE No license is required to do anything with public domain materials. This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut 1;