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WCRTOMB(3)                 Library Functions Manual                 WCRTOMB(3)

NAME
     wcrtomb - converts a wide character to a multibyte character
     (restartable)

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <wchar.h>

     size_t
     wcrtomb(char * restrict s, wchar_t wc, mbstate_t * restrict ps);

DESCRIPTION
     wcrtomb() converts the wide character given by wc to the corresponding
     multibyte character, and stores it in the array pointed to by s unless s
     is a null pointer.  This function will modify the first at most
     MB_CUR_MAX bytes of the array pointed to by s.

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

     These are the special cases:

     wc == 0       For state-dependent encodings, wcrtomb() stores a nul byte
                   preceded by special byte sequence (if any) to return to an
                   initial state in the array pointed to by s, and the state
                   object pointed to by ps also returns to an initial state.

     s == NULL     wcrtomb() just places ps into an initial state.  It is
                   equivalent to the following call:

                         wcrtomb(buf, L'\0', ps);

                   Here, buf is a dummy buffer.  In this case, wc is ignored.

     ps == NULL    mbrtowc() uses its own internal state object to keep the
                   conversion state, instead of ps mentioned in this manual
                   page.

                   Calling any other functions in Standard C Library (libc,
                   -lc) never changes the internal state of mbrtowc(), which
                   is initialized at startup time of the program.

RETURN VALUES
     wcrtomb() returns:

     positive      The number of bytes (including any shift sequences) which
                   are stored in the array.

     (size_t)-1    wc is not a valid wide character.  In this case, wcrtomb()
                   also sets errno to indicate the error.

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

     [EILSEQ]           wc is not a valid wide character.

     [EINVAL]           ps points to an invalid or uninitialized mbstate_t
                        object.

SEE ALSO
     setlocale(3), wctomb(3)

STANDARDS
     The wcrtomb() function conforms to ISO/IEC 9899/AMD1:1995 ("ISO C90,
     Amendment 1").  The restrict qualifier is added at ISO/IEC 9899:1999
     ("ISO C99").

NetBSD 10.99                   February 4, 2002                   NetBSD 10.99