WCRTOMB(3)                          Linux Programmer's Manual                          WCRTOMB(3)



NAME
       wcrtomb - convert a wide character to a multibyte sequence

SYNOPSIS
       #include <wchar.h>

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

DESCRIPTION
       The  main case for this function is when s is not NULL and wc is not a null wide character
       (L'\0').  In this case, the wcrtomb() function converts  the  wide  character  wc  to  its
       multibyte  representation and stores it at the beginning of the character array pointed to
       by s.  It updates the shift state *ps, and returns the length of said multibyte  represen‐
       tation, that is, the number of bytes written at s.

       A  different case is when s is not NULL, but wc is a null wide character (L'\0').  In this
       case, the wcrtomb() function stores at the character array  pointed  to  by  s  the  shift
       sequence  needed  to  bring  *ps  back  to the initial state, followed by a '\0' byte.  It
       updates the shift state *ps (i.e., brings it into the  initial  state),  and  returns  the
       length of the shift sequence plus one, that is, the number of bytes written at s.

       A third case is when s is NULL.  In this case, wc is ignored, and the function effectively
       returns

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

       where buf is an internal anonymous buffer.

       In all of the above cases, if ps is NULL, a static anonymous state known only to the  wcr‐
       tomb() function is used instead.

RETURN VALUE
       The wcrtomb() function returns the number of bytes that have been or would have been writ‐
       ten to the byte array at s.  If wc can not be represented as a multibyte sequence (accord‐
       ing to the current locale), (size_t) -1 is returned, and errno set to EILSEQ.

CONFORMING TO
       C99.

NOTES
       The behavior of wcrtomb() depends on the LC_CTYPE category of the current locale.

       Passing NULL as ps is not multithread safe.

SEE ALSO
       mbsinit(3), wcsrtombs(3)

COLOPHON
       This  page  is  part of release 3.74 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at http://www.kernel.org/doc/man-pages/.



GNU                                         2014-03-18                                 WCRTOMB(3)