uselocale(3)               Library Functions Manual               uselocale(3)

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

LIBRARY
       Standard C library (libc, -lc)

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 uselocale(), 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 previous 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.

STANDARDS
       POSIX.1-2008.

HISTORY
       glibc 2.3.  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 man-pages 6.7               2023-10-31                      uselocale(3)