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Updated: Wednesday, July 27, 2022
 
 

I18N::Langinfo (3)

Name

I18N::Langinfo - query locale information

Synopsis

use I18N::Langinfo;

Description

Perl Programmers Reference Guide                             I18N::Langinfo(3)



NAME
       I18N::Langinfo - query locale information

SYNOPSIS
         use I18N::Langinfo;

DESCRIPTION
       The langinfo() function queries various locale information that can be
       used to localize output and user interfaces.  It uses the current
       underlying locale, regardless of whether or not it was called from
       within the scope of "use locale".  The langinfo() function requires one
       numeric argument that identifies the locale constant to query: if no
       argument is supplied, $_ is used.  The numeric constants appropriate to
       be used as arguments are exportable from I18N::Langinfo.

       The following example will import the langinfo() function itself and
       three constants to be used as arguments to langinfo(): a constant for
       the abbreviated first day of the week (the numbering starts from Sunday
       = 1) and two more constants for the affirmative and negative answers
       for a yes/no question in the current locale.

           use I18N::Langinfo qw(langinfo ABDAY_1 YESSTR NOSTR);

           my ($abday_1, $yesstr, $nostr) =
               map { langinfo($_) } (ABDAY_1, YESSTR, NOSTR);

           print "$abday_1? [$yesstr/$nostr] ";

       In other words, in the "C" (or English) locale the above will probably
       print something like:

           Sun? [yes/no]

       but under a French locale

           dim? [oui/non]

       The usually available constants are as follows.

       o   For abbreviated and full length days of the week and months of the
           year:

               ABDAY_1 ABDAY_2 ABDAY_3 ABDAY_4 ABDAY_5 ABDAY_6 ABDAY_7
               ABMON_1 ABMON_2 ABMON_3 ABMON_4 ABMON_5 ABMON_6
               ABMON_7 ABMON_8 ABMON_9 ABMON_10 ABMON_11 ABMON_12
               DAY_1 DAY_2 DAY_3 DAY_4 DAY_5 DAY_6 DAY_7
               MON_1 MON_2 MON_3 MON_4 MON_5 MON_6
               MON_7 MON_8 MON_9 MON_10 MON_11 MON_12

       o   For the date-time, date, and time formats used by the strftime()
           function (see POSIX):

               D_T_FMT D_FMT T_FMT

       o   For the locales for which it makes sense to have ante meridiem and
           post meridiem time formats:

               AM_STR PM_STR T_FMT_AMPM

       o   For the character code set being used (such as "ISO8859-1",
           "cp850", "koi8-r", "sjis", "utf8", etc.), and for the currency
           string:

               CODESET CRNCYSTR

       o   For an alternate representation of digits, for the radix character
           used between the integer and the fractional part of decimal
           numbers, the group separator string for large-ish floating point
           numbers (yes, the final two are redundant with
           POSIX::localeconv()):

               ALT_DIGITS RADIXCHAR THOUSEP

       o   For the affirmative and negative responses and expressions:

               YESSTR YESEXPR NOSTR NOEXPR

       o   For the eras based on typically some ruler, such as the Japanese
           Emperor (naturally only defined in the appropriate locales):

               ERA ERA_D_FMT ERA_D_T_FMT ERA_T_FMT

   For systems without "nl_langinfo"
       Starting in Perl 5.28, this module is available even on systems that
       lack a native "nl_langinfo".  On such systems, it uses various methods
       to construct what that function, if present, would return.  But there
       are potential glitches.  These are the items that could be different:

       "ERA"
           Unimplemented, so returns "".

       "CODESET"
           Unimplemented, except on Windows, due to the vagaries of vendor
           locale names, returning "" on non-Windows.

       "YESEXPR"
       "YESSTR"
       "NOEXPR"
       "NOSTR"
           Only the values for English are returned.  "YESSTR" and "NOSTR"
           have been removed from POSIX 2008, and are retained here for
           backwards compatibility.  Your platform's "nl_langinfo" may not
           support them.

       "D_FMT"
           Always evaluates to %x, the locale's appropriate date
           representation.

       "T_FMT"
           Always evaluates to %X, the locale's appropriate time
           representation.

       "D_T_FMT"
           Always evaluates to %c, the locale's appropriate date and time
           representation.

       "CRNCYSTR"
           The return may be incorrect for those rare locales where the
           currency symbol replaces the radix character.  Send email to
           <mailto:perlbug@perl.org> if you have examples of it needing to
           work differently.

       "ALT_DIGITS"
           Currently this gives the same results as Linux does.  Send email to
           <mailto:perlbug@perl.org> if you have examples of it needing to
           work differently.

       "ERA_D_FMT"
       "ERA_T_FMT"
       "ERA_D_T_FMT"
       "T_FMT_AMPM"
           These are derived by using "strftime()", and not all versions of
           that function know about them.  "" is returned for these on such
           systems.

       See your nl_langinfo(3) for more information about the available
       constants.  (Often this means having to look directly at the langinfo.h
       C header file.)

   EXPORT
       By default only the "langinfo()" function is exported.

BUGS
       Before Perl 5.28, the returned values are unreliable for the
       "RADIXCHAR" and "THOUSEP" locale constants.

       Starting in 5.28, changing locales on threaded builds is supported on
       systems that offer thread-safe locale functions.  These include POSIX
       2008 systems and Windows starting with Visual Studio 2005, and this
       module will work properly in such situations.  However, on threaded
       builds on Windows prior to Visual Studio 2015, retrieving the items
       "CRNCYSTR" and "THOUSEP" can result in a race with a thread that has
       converted to use the global locale.  It is quite uncommon for a thread
       to have done this.  It would be possible to construct a workaround for
       this; patches welcome: see "switch_to_global_locale" in perlapi.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-----------------------+
       |ATTRIBUTE TYPE |   ATTRIBUTE VALUE     |
       +---------------+-----------------------+
       |Availability   | runtime/perl-532      |
       +---------------+-----------------------+
       |Stability      | Pass-through volatile |
       +---------------+-----------------------+

SEE ALSO
       perllocale, "localeconv" in POSIX, "setlocale" in POSIX,
       nl_langinfo(3).

       The langinfo() function is just a wrapper for the C nl_langinfo()
       interface.

AUTHOR
       Jarkko Hietaniemi, <jhi@hut.fi>.  Now maintained by Perl 5 porters.

COPYRIGHT AND LICENSE
       Copyright 2001 by Jarkko Hietaniemi

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.



NOTES
       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       http://www.cpan.org/src/5.0/perl-5.32.0.tar.gz.

       Further information about this software can be found on the open source
       community website at https://www.perl.org/.



perl v5.32.0                      2020-06-14                 I18N::Langinfo(3)