WCSRTOMBS(3)               POSIX Programmer's Manual              WCSRTOMBS(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
       wcsnrtombs, wcsrtombs -- convert a wide-character string to a character
       string (restartable)

SSYYNNOOPPSSIISS
       #include <wchar.h>

       size_t wcsnrtombs(char *restrict _d_s_t, const wchar_t **restrict _s_r_c,
           size_t _n_w_c, size_t _l_e_n, mbstate_t *restrict _p_s);
       size_t wcsrtombs(char *restrict _d_s_t, const wchar_t **restrict _s_r_c,
           size_t _l_e_n, mbstate_t *restrict _p_s);

DDEESSCCRRIIPPTTIIOONN
       For _w_c_s_r_t_o_m_b_s(): 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_r_t_o_m_b_s() function shall convert a sequence of wide characters
       from the array indirectly pointed to by _s_r_c into a sequence of
       corresponding characters, beginning in the conversion state described
       by the object pointed to by _p_s.  If _d_s_t is not a null pointer, the
       converted characters shall then be stored into the array pointed to by
       _d_s_t.  Conversion continues up to and including a terminating null wide
       character, which shall also be stored. Conversion shall stop earlier in
       the following cases:

        *  When a code is reached that does not correspond to a valid
           character

        *  When the next character would exceed the limit of _l_e_n total bytes
           to be stored in the array pointed to by _d_s_t (and _d_s_t is not a null
           pointer)

       Each conversion shall take place as if by a call to the _w_c_r_t_o_m_b()
       function.

       If _d_s_t is not a null pointer, the pointer object pointed to by _s_r_c
       shall be assigned either a null pointer (if conversion stopped due to
       reaching a terminating null wide character) or the address just past
       the last wide character converted (if any). If conversion stopped due
       to reaching a terminating null wide character, the resulting state
       described shall be the initial conversion state.

       If _p_s is a null pointer, the _w_c_s_r_t_o_m_b_s() function shall use its own
       internal mmbbssttaattee__tt object, which is initialized at program start-up to
       the initial conversion state. Otherwise, the mmbbssttaattee__tt object pointed
       to by _p_s shall be used to completely describe the current conversion
       state of the associated character sequence.

       The _w_c_s_n_r_t_o_m_b_s() and _w_c_s_r_t_o_m_b_s() functions need not be thread-safe if
       called with a NULL _p_s argument.

       The _w_c_s_n_r_t_o_m_b_s() function shall be equivalent to the _w_c_s_r_t_o_m_b_s()
       function, except that the conversion is limited to the first _n_w_c wide
       characters.

       The _w_c_s_r_t_o_m_b_s() function shall not change the setting of _e_r_r_n_o if
       successful.

       The behavior of these functions shall be affected by the _L_C___C_T_Y_P_E
       category of the current locale.

       The implementation shall behave as if no function defined in System
       Interfaces volume of POSIX.1-2017 calls these functions.

RREETTUURRNN VVAALLUUEE
       If conversion stops because a code is reached that does not correspond
       to a valid character, an encoding error occurs. In this case, these
       functions shall store the value of the macro [[EEIILLSSEEQQ]] in _e_r_r_n_o and
       return (ssiizzee__tt)-1; the conversion state is undefined.  Otherwise, these
       functions shall return the number of bytes in the resulting character
       sequence, not including the terminating null (if any).

EERRRROORRSS
       These functions shall fail if:

       EEIILLSSEEQQ A wide-character code does not correspond to a valid character.

       These functions may fail if:

       EEIINNVVAALL _p_s points to an object that contains an invalid conversion
              state.

       _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
       None.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _m_b_s_i_n_i_t(), _w_c_r_t_o_m_b()

       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                         WCSRTOMBS(3)
