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WCSXFRM(3P)                POSIX Programmer's Manual               WCSXFRM(3P)
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
       wcsxfrm, wcsxfrm_l -- wide-character string transformation
SYNOPSIS
       #include <wchar.h>
       size_t wcsxfrm(wchar_t *restrict ws1, const wchar_t *restrict ws2,
           size_t n);
       size_t wcsxfrm_l(wchar_t *restrict ws1, const wchar_t *restrict ws2,
           size_t n, locale_t locale);
DESCRIPTION
       For wcsxfrm(): The functionality described on this  reference  page  is
       aligned  with the ISO C standard. Any conflict between the requirements
       described here and the ISO C standard is unintentional. This volume  of
       POSIX.1-2008 defers to the ISO C standard.
       The  wcsxfrm() and wcsxfrm_l() functions shall transform the wide-char-
       acter string pointed to by ws2 and place the  resulting  wide-character
       string  into  the array pointed to by ws1.  The transformation shall be
       such that if wcscmp() is applied to two transformed  wide  strings,  it
       shall  return  a  value  greater than, equal to, or less than 0, corre-
       sponding to the result of wcscoll() and wcscoll_l() applied to the same
       two  original  wide-character strings, and the same LC_COLLATE category
       of the current locale or the locale  object  locale,  respectively.  No
       more  than  n  wide-character  codes shall be placed into the resulting
       array pointed to by ws1, including the terminating null  wide-character
       code.  If  n  is  0,  ws1 is permitted to be a null pointer. If copying
       takes place between objects that overlap, the behavior is undefined.
       The wcsxfrm() and wcsxfrm_l() functions shall not change the setting of
       errno if successful.
       Since  no return value is reserved to indicate an error, an application
       wishing to check for error situations should set errno to 0, then  call
       wcsxfrm() or wcsxfrm_l(), then check errno.
       The  behavior is undefined if the locale argument to wcsxfrm_l() is the
       special locale object LC_GLOBAL_LOCALE or is not a valid locale  object
       handle.
RETURN VALUE
       The  wcsxfrm() and wcsxfrm_l() functions shall return the length of the
       transformed wide-character string (not including the  terminating  null
       wide-character  code). If the value returned is n or more, the contents
       of the array pointed to by ws1 are unspecified.
       On error, the wcsxfrm() and wcsxfrm_l() functions may set errno, but no
       return value is reserved to indicate an error.
ERRORS
       These functions may fail if:
       EINVAL The  wide-character string pointed to by ws2 contains wide-char-
              acter codes outside the domain of the collating sequence.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       The transformation function is such that two transformed wide-character
       strings can be ordered by wcscmp() as appropriate to collating sequence
       information in the current locale (category LC_COLLATE).
       The fact that when n is 0 ws1 is permitted to be a null pointer is use-
       ful  to  determine the size of the ws1 array prior to making the trans-
       formation.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       wcscmp(), wcscoll()
       The Base Definitions volume of POSIX.1-2008, <wchar.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 Electri-
       cal 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.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                          WCSXFRM(3P)