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

NAME
       uselocale - set/get the locale for the calling thread

SYNOPSIS
       #include <locale.h>

       locale_t uselocale(locale_t newloc);

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

       uselocale():
           Since glibc 2.10:
               _XOPEN_SOURCE >= 700
           Before glibc 2.10:
               _GNU_SOURCE

DESCRIPTION
       The  uselocale()  function sets the current locale for the calling thread, and returns the thread's previously current locale.  After a successful call to uselo‐
       cale(), any calls by this thread to functions that depend on the locale will operate as though the locale has been set to newloc.

       The newloc argument can have one of the following values:

       A handle returned by a call to newlocale(3) or duplocale(3)
              The calling thread's current locale is set to the specified locale.

       The special locale object handle LC_GLOBAL_LOCALE
              The calling thread's current locale is set to the global locale determined by setlocale(3).

       (locale_t) 0
              The calling thread's current locale is left unchanged (and the current locale is returned as the function result).

RETURN VALUE
       On success, uselocale() returns the locale handle that was set by the previous call to uselocale() in this thread, or LC_GLOBAL_LOCALE if there was no such  pre‐
       vious call.  On error, it returns (locale_t) 0, and sets errno to indicate the error.

ERRORS
       EINVAL newloc does not refer to a valid locale object.

VERSIONS
       The uselocale() function first appeared in version 2.3 of the GNU C library.

CONFORMING TO
       POSIX.1-2008.

NOTES
       Unlike  setlocale(3), uselocale() does not allow selective replacement of individual locale categories.  To employ a locale that differs in only a few categories
       from the current locale, use calls to duplocale(3) and newlocale(3) to obtain a locale object equivalent to the current locale and modify the desired  categories
       in that object.

EXAMPLES
       See newlocale(3) and duplocale(3).

SEE ALSO
       locale(1), duplocale(3), freelocale(3), newlocale(3), setlocale(3), locale(5), locale(7)

Linux                                                                          2021-03-22                                                                   USELOCALE(3)