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duplocale(3p) — Linux manual page

DUPLOCALE(3P)           POSIX Programmer's ManualDUPLOCALE(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_tlocobj);

DESCRIPTION        top

       Theduplocale() function shall create a duplicate copy of the       locale object referenced by thelocobj argument.       If thelocobj argument is LC_GLOBAL_LOCALE,duplocale() shall       create a new locale object containing a copy of the global locale       determined by thesetlocale() function.       The behavior is undefined if thelocobj argument is not a valid       locale object handle.

RETURN VALUE        top

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

ERRORS        top

       Theduplocale() function shall fail if:ENOMEMThere 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 theLC_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 theduplocale() 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 tonewlocale() following theduplocale() call.       As with thenewlocale() function, handles for locale objects       created by theduplocale() function should be released by a       corresponding call tofreelocale().       Theduplocale() function can also be used in conjunction withuselocale((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 asisalnum_l() results in       undefined behavior, but applications can convert it into a usable       locale object by usingduplocale().

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

freelocale(3p),newlocale(3p),uselocale(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 athttp://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, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017DUPLOCALE(3P)

Pages that refer to this page:locale.h(0p), freelocale(3p), newlocale(3p), uselocale(3p)

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