nl_langinfo

NL_LANGINFO(3)             Linux Programmer's Manual            NL_LANGINFO(3)



NAME
       nl_langinfo, nl_langinfo_l - query language and locale information

SYNOPSIS
       #include <langinfo.h>

       char *nl_langinfo(nl_item item);

       char *nl_langinfo_l(nl_item item, locale_t locale);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       nl_langinfo_l():
           Since glibc 2.24:
               _POSIX_C_SOURCE >= 200809L
           Glibc 2.23 and earlier:
               _POSIX_C_SOURCE >= 200112L

DESCRIPTION
       The nl_langinfo() and nl_langinfo_l() functions provide access to
       locale information in a more flexible way than localeconv(3).
       nl_langinfo() returns a string which is the value corresponding to item
       in the program's current global locale.  nl_langinfo() returns a string
       which is the value corresponding to item for the locale identified by
       the locale object locale, which was previously created by newlocale(1).
       Individual and additional elements of the locale categories can be
       queried.

       Examples for the locale elements that can be specified in item using
       the constants defined in <langinfo.h> are:

       CODESET (LC_CTYPE)
              Return a string with the name of the character encoding used in
              the selected locale, such as "UTF-8", "ISO-8859-1", or
              "ANSI_X3.4-1968" (better known as US-ASCII).  This is the same
              string that you get with "locale charmap".  For a list of
              character encoding names, try "locale -m" (see locale(1)).

       D_T_FMT (LC_TIME)
              Return a string that can be used as a format string for
              strftime(3) to represent time and date in a locale-specific way.

       D_FMT (LC_TIME)
              Return a string that can be used as a format string for
              strftime(3) to represent a date in a locale-specific way.

       T_FMT (LC_TIME)
              Return a string that can be used as a format string for
              strftime(3) to represent a time in a locale-specific way.

       DAY_{1–7} (LC_TIME)
              Return name of the n-th day of the week. [Warning: this follows
              the US convention DAY_1 = Sunday, not the international
              convention (ISO 8601) that Monday is the first day of the week.]

       ABDAY_{1–7} (LC_TIME)
              Return abbreviated name of the n-th day of the week.

       MON_{1–12} (LC_TIME)
              Return name of the n-th month.

       ABMON_{1–12} (LC_TIME)
              Return abbreviated name of the n-th month.

       RADIXCHAR (LC_NUMERIC)
              Return radix character (decimal dot, decimal comma, etc.).

       THOUSEP (LC_NUMERIC)
              Return separator character for thousands (groups of three
              digits).

       YESEXPR (LC_MESSAGES)
              Return a regular expression that can be used with the regex(3)
              function to recognize a positive response to a yes/no question.

       NOEXPR (LC_MESSAGES)
              Return a regular expression that can be used with the regex(3)
              function to recognize a negative response to a yes/no question.

       CRNCYSTR (LC_MONETARY)
              Return the currency symbol, preceded by "-" if the symbol should
              appear before the value, "+" if the symbol should appear after
              the value, or "." if the symbol should replace the radix
              character.

       The above list covers just some examples of items that can be
       requested.  For a more detailed list, consult The GNU C Library
       Reference Manual.

RETURN VALUE
       On success, these functions return a pointer to a string which is the
       value corresponding to item in the specified locale.

       If no locale has been selected by setlocale(3) for the appropriate
       category, nl_langinfo() return a pointer to the corresponding string in
       the "C" locale.  The same is true of nl_langinfo_l() if locale
       specifies a locale where langinfo data is not defined.

       If item is not valid, a pointer to an empty string is returned.

       The pointer returned by these functions may point to static data that
       may be overwritten, or the pointer itself may be invalidated, by a
       subsequent call to nl_langinfo(), nl_langinfo_l(), or setlocale(3).
       The same statements apply to nl_langinfo_l() if the locale object
       referred to by locale is freed or modified by freelocale(3) or
       newlocale(3).

       POSIX specifies that the application may not modify the string returned
       by these functions.

ATTRIBUTES
       For an explanation of the terms used in this section, see
       attributes(7).

       ┌──────────────┬───────────────┬────────────────┐
       │Interface     Attribute     Value          │
       ├──────────────┼───────────────┼────────────────┤
       │nl_langinfo() │ Thread safety │ MT-Safe locale │
       └──────────────┴───────────────┴────────────────┘
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, SUSv2.

NOTES
       The behavior of nl_langinfo_l() is undefined if locale is the special
       locale object LC_GLOBAL_LOCALE or is not a valid locale object handle.

EXAMPLE
       The following program sets the character type and the numeric locale
       according to the environment and queries the terminal character set and
       the radix character.

       #include <langinfo.h>
       #include <locale.h>
       #include <stdio.h>
       #include <stdlib.h>

       int
       main(int argc, char *argv[])
       {
           setlocale(LC_CTYPE, "");
           setlocale(LC_NUMERIC, "");

           printf("%s\n", nl_langinfo(CODESET));
           printf("%s\n", nl_langinfo(RADIXCHAR));

           exit(EXIT_SUCCESS);
       }

SEE ALSO
       locale(1), localeconv(3), setlocale(3), charsets(7), locale(7)

       The GNU C Library Reference Manual

COLOPHON
       This page is part of release 5.02 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



GNU                               2019-03-06                    NL_LANGINFO(3)