WCTOMB(3) Library Functions Manual WCTOMB(3)

wctomb — converts a wide character to a multibyte character

Standard C Library (libc, -lc)

#include <stdlib.h>

int
wctomb(char * s, wchar_t wchar);

The () converts the wide character wchar to the corresponding multibyte character, and stores it in the array pointed to by s. wctomb() may store at most MB_CUR_MAX bytes in the array.

In state-dependent encoding, () may store the special sequence to change the conversion state before an actual multibyte character into the array pointed to by s. If wchar is a nul wide character (‘\0’), this function sets its own internal state to an initial conversion state.

Calling any other functions in Standard C Library (libc, -lc) never changes the internal state of (), except changing the LC_CTYPE category of the current locale by calling setlocale(3). Such setlocale(3) calls cause the internal state of this function to be indeterminate.

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

There is one special case:

s == NULL
() 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.

Normally, wctomb() returns:

positive
Number of bytes for the valid multibyte character pointed to by s. There are no cases that the value returned is greater than the value of the MB_CUR_MAX macro.
-1
wchar is an invalid wide character.

If s is equal to NULL, wctomb() returns:

0
The current encoding is state-independent.
non-zero
The current encoding is state-dependent.

No errors are defined.

setlocale(3)

The wctomb() function conforms to ANSI X3.159-1989 (“ANSI C89”).

February 3, 2002 NetBSD 11.0