wcsxfrm(3p) — Linux manual page

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.1‐2017 defers to the ISO C
       standard.

       The wcsxfrm() and wcsxfrm_l() functions 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() 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-
              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 current 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 transformation.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       wcscmp(3p), wcscoll(3p)

       The Base Definitions volume of POSIX.1‐2017, wchar.h(0p)

COPYRIGHT

       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 at http://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, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                       WCSXFRM(3P)

Pages that refer to this page: wchar.h(0p), setlocale(3p), wcscoll(3p)

---