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WCSTOMBS(3)                Library Functions Manual                WCSTOMBS(3)

NAME
     wcstombs - converts a wide-character string to a multibyte character
     string

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <stdlib.h>

     size_t
     wcstombs(char * restrict s, const wchar_t * restrict pwcs, size_t n);

DESCRIPTION
     wcstombs() converts the nul-terminated wide-character string pointed to
     by pwcs to the corresponding multibyte character string, and stores it in
     the array pointed to by s.  This function may modify the first at most n
     bytes of the array pointed to by s.  Each character will be converted as
     if wctomb(3) is continuously called, except the internal state of
     wctomb(3) will not be affected.

     For state-dependent encoding, the wcstombs() implies the result multibyte
     character string pointed to by s always to begin with an initial state.

     The behaviour of wcstombs() is affected by the LC_CTYPE category of the
     current locale.

     These are the special cases:

     s == NULL     The wcstombs() returns the number of bytes to store the
                   whole multibyte character string corresponding to the wide-
                   character string pointed to by pwcs.  In this case, n is
                   ignored.

     pwcs == NULL  Undefined (may cause the program to crash).

RETURN VALUES
     wcstombs() returns:

     0 or positive
                   Number of bytes stored in the array pointed to by s.  There
                   are no cases that the value returned is greater than n
                   (unless s is a null pointer).  If the return value is equal
                   to n, the string pointed to by s will not be nul-
                   terminated.

     (size_t)-1    pwcs points to a string containing an invalid wide
                   character.  wcstombs() also sets errno to indicate the
                   error.

ERRORS
     wcstombs() may cause an error in the following case:

     [EILSEQ]           pwcs points to a string containing an invalid wide
                        character.

SEE ALSO
     mbstowcs(3), setlocale(3), wctomb(3)

STANDARDS
     The wcstombs() function conforms to ANSI X3.159-1989 ("ANSI C89").  The
     restrict qualifier is added at ISO/IEC 9899:1999 ("ISO C99").

NetBSD 10.99                    March 16, 2011                    NetBSD 10.99