wcsrtombs, wcsrtombs_s

Header: <wchar.h>

Converts a sequence of wide characters from the array whose first element is pointed to by *src to its narrow multibyte representation that begins in the conversion state described by *ps. If dst is not null, converted characters are stored in the successive elements of the char array pointed to by dst. No more than len bytes are written to the destination array. Each character is converted as if by a call to wcrtomb. The conversion stops if: The null character L’\0’ was converted and stored. The bytes stored in this case are the unshift sequence (if necessary) followed by ‘\0’, *src is set to null pointer value and *ps represents the initial shift state.A wchar_t was found that does not correspond to a valid character in the current C locale. *src is set to point at the first unconverted wide character.the next multibyte character to be stored would exceed len. *src is set to point at the first unconverted wide character. This condition is not checked if dst is a null pointer.

# Declarations

size_t wcsrtombs( char *dst, const wchar_t **src, size_t len, mbstate_t* ps );

(since C95) (until C99)

size_t wcsrtombs( char *restrict dst, const wchar_t **restrict src, size_t len,
mbstate_t *restrict ps );

(since C99)

errno_t wcsrtombs_s( size_t *restrict retval, char *restrict dst, rsize_t dstsz,
const wchar_t **restrict src, rsize_t len,
mbstate_t *restrict ps );

(since C11)

# Parameters

dst: pointer to narrow character array where the multibyte characters will be stored
src: pointer to pointer to the first element of a null-terminated wide string
len: number of bytes available in the array pointed to by dst
ps: pointer to the conversion state object
dstsz: max number of bytes that will be written (size of the dst array)
retval: pointer to a size_t object where the result will be stored

# Example

#include <stdio.h>
#include <locale.h>
#include <string.h>
#include <wchar.h>
 
void print_wide(const wchar_t* wstr)
{
    mbstate_t state;
    memset(&state, 0, sizeof state);
    size_t len = 1 + wcsrtombs(NULL, &wstr, 0, &state);
    char mbstr[len];
    wcsrtombs(mbstr, &wstr, len, &state);
    printf("Multibyte string: %s\n", mbstr);
    printf("Length, including '\\0': %zu\n", len);
}
 
int main(void)
{
    setlocale(LC_ALL, "en_US.utf8");
    print_wide(L"z\u00df\u6c34\U0001f34c"); // or L"zß水🍌"
}

wcsrtombs, wcsrtombs_s

# Declarations

# Parameters

# Example

# See also