PROLOG

       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

       duplocale — duplicate a locale object

SYNOPSIS

       #include <locale.h>

       locale_t duplocale(locale_t locobj);

DESCRIPTION

       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

       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

       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

   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

       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

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       freelocale(), newlocale(), uselocale()

       The Base Definitions volume of POSIX.1‐2008, <locale.h>

COPYRIGHT

       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(3POSIX)