WCSXFRM(3)                 POSIX Programmer's Manual                WCSXFRM(3)



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.

NNAAMMEE
       wcsxfrm, wcsxfrm_l -- wide-character string transformation

SSYYNNOOPPSSIISS
       #include <wchar.h>

       size_t wcsxfrm(wchar_t *restrict _w_s_1, const wchar_t *restrict _w_s_2,
           size_t _n);
       size_t wcsxfrm_l(wchar_t *restrict _w_s_1, const wchar_t *restrict _w_s_2,
           size_t _n, locale_t _l_o_c_a_l_e);

DDEESSCCRRIIPPTTIIOONN
       For _w_c_s_x_f_r_m(): 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 _w_c_s_x_f_r_m() and _w_c_s_x_f_r_m___l() functions shall transform the wide-
       character string pointed to by _w_s_2 and place the resulting wide-
       character string into the array pointed to by _w_s_1.  The transformation
       shall be such that if _w_c_s_c_m_p() 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 _w_c_s_c_o_l_l() and _w_c_s_c_o_l_l___l() applied to
       the same two original wide-character strings, and the same _L_C___C_O_L_L_A_T_E
       category of the current locale or the locale object _l_o_c_a_l_e,
       respectively. No more than _n wide-character codes shall be placed into
       the resulting array pointed to by _w_s_1, including the terminating null
       wide-character code. If _n is 0, _w_s_1 is permitted to be a null pointer.
       If copying takes place between objects that overlap, the behavior is
       undefined.

       The _w_c_s_x_f_r_m() and _w_c_s_x_f_r_m___l() functions shall not change the setting of
       _e_r_r_n_o if successful.

       Since no return value is reserved to indicate an error, an application
       wishing to check for error situations should set _e_r_r_n_o to 0, then call
       _w_c_s_x_f_r_m() or _w_c_s_x_f_r_m___l(), then check _e_r_r_n_o.

       The behavior is undefined if the _l_o_c_a_l_e argument to _w_c_s_x_f_r_m___l() is the
       special locale object LC_GLOBAL_LOCALE or is not a valid locale object
       handle.

RREETTUURRNN VVAALLUUEE
       The _w_c_s_x_f_r_m() and _w_c_s_x_f_r_m___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 _w_s_1 are unspecified.

       On error, the _w_c_s_x_f_r_m() and _w_c_s_x_f_r_m___l() functions may set _e_r_r_n_o, but no
       return value is reserved to indicate an error.

EERRRROORRSS
       These functions may fail if:

       EEIINNVVAALL The wide-character string pointed to by _w_s_2 contains wide-
              character codes outside the domain of the collating sequence.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       The transformation function is such that two transformed wide-character
       strings can be ordered by _w_c_s_c_m_p() as appropriate to collating sequence
       information in the current locale (category _L_C___C_O_L_L_A_T_E).

       The fact that when _n is 0 _w_s_1 is permitted to be a null pointer is
       useful to determine the size of the _w_s_1 array prior to making the
       transformation.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _w_c_s_c_m_p(), _w_c_s_c_o_l_l()

       The Base Definitions volume of POSIX.1-2017, <<wwcchhaarr..hh>>

CCOOPPYYRRIIGGHHTT
       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(3)
