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uselocale(3p) — Linux manual page

PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT 

USELOCALE(3P)           POSIX Programmer's Manual           USELOCALE(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       uselocale — use locale in current thread

SYNOPSIS         top

       #include <locale.h>

       locale_t uselocale(locale_t newloc);

DESCRIPTION         top

       The uselocale() function shall set or query the current locale for
       the calling thread.

       The value for the newloc argument shall be one of the following:

        1. A value returned by the newlocale() or duplocale() functions

        2. The special locale object descriptor LC_GLOBAL_LOCALE

        3. (locale_t)0

       If the newloc argument is (locale_t)0, the current locale shall
       not be changed; this value can be used to query the current locale
       setting. If the newloc argument is LC_GLOBAL_LOCALE, any thread-
       local locale for the calling thread shall be uninstalled; the
       thread shall again use the global locale as the current locale,
       and changes to the global locale shall affect the thread.
       Otherwise, the locale represented by newloc shall be installed as
       a thread-local locale to be used as the current locale for the
       calling thread.

       Once the uselocale() function has been called to install a thread-
       local locale, the behavior of every interface using data from the
       current locale shall be affected for the calling thread. The
       current locale for other threads shall remain unchanged.

RETURN VALUE         top

       Upon successful completion, the uselocale() function shall return
       a handle for the thread-local locale that was in use as the
       current locale for the calling thread on entry to the function, or
       LC_GLOBAL_LOCALE if no thread-local locale was in use. Otherwise,
       uselocale() shall return (locale_t)0 and set errno to indicate the
       error.

ERRORS         top

       The uselocale() function may fail if:

       EINVAL newloc is not a valid locale object and is not (locale_t)0.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       Unlike the setlocale() function, the uselocale() function does not
       allow replacing some locale categories only. Applications that
       need to install a locale which differs only in a few categories
       must use newlocale() to change a locale object equivalent to the
       currently used locale and install it.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       duplocale(3p), freelocale(3p), newlocale(3p), setlocale(3p)

       The Base Definitions volume of POSIX.1‐2017, locale.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics Engineers,
       Inc and The Open Group.  In the event of any discrepancy between
       this version and the original IEEE and The Open Group Standard,
       the original IEEE and The Open Group Standard is the referee
       document. The original Standard can be obtained online at
       http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                2017                     USELOCALE(3P)

Pages that refer to this page: locale.h(0p),  duplocale(3p),  freelocale(3p),  isalnum(3p),  isalpha(3p),  isblank(3p),  iscntrl(3p),  isgraph(3p),  islower(3p),  isprint(3p),  ispunct(3p),  isspace(3p),  isupper(3p),  iswalnum(3p),  iswalpha(3p),  iswblank(3p),  iswcntrl(3p),  iswctype(3p),  iswdigit(3p),  iswgraph(3p),  iswlower(3p),  iswprint(3p),  iswpunct(3p),  iswspace(3p),  iswupper(3p),  iswxdigit(3p),  localeconv(3p),  newlocale(3p),  nl_langinfo(3p),  setlocale(3p),  strftime(3p),  tolower(3p),  toupper(3p),  towlower(3p),  towupper(3p)

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