1WCRTOMB(3)                 Linux Programmer's Manual                WCRTOMB(3)
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NAME

6       wcrtomb - convert a wide character to a multibyte sequence
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SYNOPSIS

9       #include <wchar.h>
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11       size_t wcrtomb(char *s, wchar_t wc, mbstate_t *ps);
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DESCRIPTION

14       The  main  case  for  this function is when s is not NULL and wc is not
15       L'\0'.  In this case, the wcrtomb() function converts the wide  charac‐
16       ter  wc  to its multibyte representation and stores it at the beginning
17       of the character array pointed to by s. It updates the shift state *ps,
18       and  returns the length of said multibyte representation, i.e. the num‐
19       ber of bytes written at s.
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21       A different case is when s is not NULL but wc is L'\0'.  In  this  case
22       the  wcrtomb()  function  stores at the character array pointed to by s
23       the shift sequence needed to bring *ps back to the initial state,  fol‐
24       lowed  by  a  '\0' byte. It updates the shift state *ps (i.e. brings it
25       into the initial state), and returns the length of the  shift  sequence
26       plus one, i.e. the number of bytes written at s.
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28       A  third  case  is  when s is NULL. In this case wc is ignored, and the
29       function effectively returns  wcrtomb(buf,L'\0',ps)  where  buf  is  an
30       internal anonymous buffer.
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32       In  all of the above cases, if ps is a NULL pointer, a static anonymous
33       state only known to the wcrtomb() function is used instead.
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RETURN VALUE

36       The wcrtomb() function returns the number of bytes that  have  been  or
37       would have been written to the byte array at s. If wc can not be repre‐
38       sented as a multibyte  sequence  (according  to  the  current  locale),
39       (size_t)(-1) is returned, and errno set to EILSEQ.
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CONFORMING TO

42       C99.
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SEE ALSO

45       wcsrtombs(3)
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NOTES

48       The behaviour of wcrtomb() depends on the LC_CTYPE category of the cur‐
49       rent locale.
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51       Passing NULL as ps is not multi-thread safe.
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55GNU                               1999-07-25                        WCRTOMB(3)