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

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

       duplocale — duplicate a locale object

SYNOPSIS         top

       #include <locale.h>

       locale_t duplocale(locale_t locobj);

DESCRIPTION         top

       The duplocale() function shall create a duplicate copy of the locale
       object referenced by the locobj argument.

       If the locobj argument is LC_GLOBAL_LOCALE, duplocale() shall create
       a new locale object containing a copy of the global locale determined
       by the setlocale() function.

       The behavior is undefined if the locobj argument is not a valid
       locale object handle.

RETURN VALUE         top

       Upon successful completion, the duplocale() function shall return a
       handle for a new locale object. Otherwise, duplocale() shall return
       (locale_t)0 and set errno to indicate the error.

ERRORS         top

       The duplocale() function shall fail if:

       ENOMEM There is not enough memory available to create the locale
              object or load the locale data.

       The following sections are informative.

EXAMPLES         top

   Constructing an Altered Version of an Existing Locale Object
       The following example shows a code fragment to create a slightly
       altered version of an existing locale object. The function takes a
       locale object and a locale name and it replaces the LC_TIME category
       data in the locale object with that from the named locale.

           #include <locale.h>
           ...

           locale_t
           with_changed_lc_time (locale_t obj, const char *name)
           {

               locale_t retval = duplocale (obj);
               if (retval != (locale_t) 0)
               {
                   locale_t changed = newlocale (LC_TIME_MASK, name, retval);
                   if (changed == (locale_t) 0)
                       /* An error occurred. Free all allocated resources. */
                       freelocale (retval);
                   retval = changed;
               }
               return retval; }
           }

APPLICATION USAGE         top

       The use of the duplocale() function is recommended for situations
       where a locale object is being used in multiple places, and it is
       possible that the lifetime of the locale object might end before all
       uses are finished. Another reason to duplicate a locale object is if
       a slightly modified form is needed.  This can be achieved by a call
       to newlocale() following the duplocale() call.

       As with the newlocale() function, handles for locale objects created
       by the duplocale() function should be released by a corresponding
       call to freelocale().

       The duplocale() function can also be used in conjunction with
       uselocale((locale_t)0).  This returns the locale in effect for the
       calling thread, but can have the value LC_GLOBAL_LOCALE. Passing
       LC_GLOBAL_LOCALE to functions such as isalnum_l() results in
       undefined behavior, but applications can convert it into a usable
       locale object by using duplocale().

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       freelocale(3p), newlocale(3p), uselocale(3p)

       The Base Definitions volume of POSIX.1‐2008, locale.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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.unix.org/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                 2013                       DUPLOCALE(3P)