wctomb - converts a wide character to a multibyte character
Standard C Library (libc, -lc)
wctomb(char * s, const wchar_t wchar);
The wctomb() converts the wide character wchar to the corresponding
multibyte character, and store it to the array pointed by s. The
wctomb() may store at most MB_CUR_MAX bytes to the array.
In state-dependent encoding, the wctomb() may store the special sequence
to change the conversion state before an actual multibyte character into
the array pointed s. If wchar is null wide character (L'\0'), this function
places its own internal state to an initial conversion state.
Calling any other functions in the Standard C Library (libc, -lc) never
change the internal state of the wctomb(), except for calling
setlocale(3) with changing LC_CTYPE category of the current locale. Such
setlocale(3) call causes the internal state of this function to be indeterminate.
The behaviour of the wctomb() is affected by LC_CTYPE category of the
There is a special case:
s == NULL wctomb() initializes its own internal state to an initial
state, and determines whether the current encoding is
state-dependent. This function returns 0 if the encoding
is state-independent, otherwise non-zero. In this case,
wchar is completely ignored.
In the usual case, the wctomb() returns:
positive number of bytes for the valid multibyte character pointed
by s. There is no cases that the value returned is greater
than n or the value of MB_CUR_MAX macro.
-1 wchar is an invalid wide character.
In the case that s is equal to NULL, the mbtowc() returns:
0 The current encoding is state-independent.
non-zero The current encoding is state-dependent.
No errors are defined.
The wctomb() function conforms to ANSI X3.159-1989 (``ANSI C'').
BSD February 3, 2002 BSD
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