### wcrtomb -- Convert Wide Character to Multibyte Character

Format

>     #include <wchar.h>
>     int wcrtomb(char *dest, wchar_t wc, mbstate_t *ps);

Language Level: ANSI 93
wcrtomb is a restartable version of wctomb, and performs the same function. It first determines the length of the wide character pointed to by wc. It then converts the wide character to the corresponding multibyte character, and stores the converted character in the location pointed to by dest, if dest is not a null pointer. A maximum of MB_CUR_MAX bytes are stored.

With wcrtomb, you can switch from one multibyte string to another. On systems that support shift states, ps represents the initial shift state of the string (0). If you read in only part of the string, wcrtomb sets ps to the string's shift state at the point you stopped. You can then call wcrtomb again for that string and pass in the updated ps value to continue reading where you left off.

Because both OS/2 and Windows do not have shift states, the ps parameter is provided only for compatibility with other ANSI/ISO platforms. This product ignores the value passed for ps.

The behavior of wcrtomb is affected by the LC_CTYPE category of the current locale.

Return Value
If dest is a null pointer, wcrtomb returns 0. If dest is not a null pointer, wcrtomb returns the number of bytes stored in dest. If wc is not a valid wide character, wcrtomb sets errno to EILSEQ and returns -1.

Example
This example uses wcrtomb to convert two wide-character strings to multibyte strings.

    #include <stdlib.h>
    #include <stdio.h>
    #include <locale.h>
    #include <wchar.h>

    #define SIZE  20
    #define LOCNAME "ja_jp.ibm-932"

    int main(void)
    {
       wchar_t    wcs1[] = L"abc";
       wchar_t    wcs2[] = L"Ax8142" L"C";
       mbstate_t  ss1 = 0;
       mbstate_t  ss2 = 0;
       size_t     length1 = 0;
       size_t     length2 = 0;
       char       mb1[SIZE], mb2[SIZE];
       int        i;

       if (NULL == setlocale(LC_ALL, LOCNAME)) {
          printf("Locale \"%s\" could not be loaded\n", LOCNAME);
          exit(1);
       }
       for (i = 0; i <=2; ++i) {
          length1 += wcrtomb(mb1 + length1, *(wcs1 + i), &ss1);
          length2 += wcrtomb(mb2 + length2, *(wcs2 + i), &ss2);
       }
       mb1[length1] = 0;
       mb2[length2] = 0;
       printf("The first multibyte string is: <%s>\n", mb1);
       printf("The second multibyte string is: <%s>\n", mb2);
       return 0;

       /********************************************************
          The output should be similiar to:

          The first multibyte string is: <abc>
          The second multibyte string is: <A BC>
       ********************************************************/
    }

mblen -- Determine Length of Multibyte Character
mbrlen -- Calculate Length of Multibyte Character
mbrtowc -- Convert Multibyte Character to Wide Character
mbsrtowcs -- Convert Multibyte String to Wide-Character String
wcsrtombs -- Convert Wide-Character String to Multibyte String
wctomb -- Convert Wide Character to Multibyte Character
wchar.h