linux man page for wcsxfrm

WCSXFRM(P)						     POSIX Programmer's Manual							WCSXFRM(P)

NAME
       wcsxfrm - wide-character string transformation

SYNOPSIS
       #include <wchar.h>

       size_t wcsxfrm(wchar_t *restrict ws1, const wchar_t *restrict ws2,
	      size_t n);

DESCRIPTION
       The  wcsxfrm()  function shall transform the wide-character 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, corresponding to the result of wcscoll() applied to the same two original wide-character
       strings. 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() function 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(), then check errno.

RETURN VALUE
       The  wcsxfrm() function 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() function may set errno, but no return value is reserved to indicate an error.

ERRORS
       The wcsxfrm() function may fail if:

       EINVAL The wide-character string pointed to by ws2 contains wide-character 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 program's locale (category LC_COLLATE ).

       The fact that when n is 0 ws1 is permitted to be a null pointer is useful 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 IEEE Std 1003.1-2001, <wchar.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 .

IEEE
/The Open Group						       2003								WCSXFRM(P)