为什么mblen（）总是返回1？

Question

Consider following code:

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

#define MAX 64

void main(void)
{
    char napis[] = "coś żółtego";
    int i;
    wchar_t bufor[MAX];
    int ret;

    setlocale(LC_CTYPE, "");

    printf("zwykły string [%s] długość %d\n", napis, mblen(napis, MAX)); // <---

    ret = mbstowcs(bufor, napis, sizeof bufor);
    if (ret == MAX)
        bufor[MAX-1] = '\0';
    if (ret > 0)
    {
        printf("16 bitowy string: [%ls] długość napisu %d długość %d\n", bufor, mblen(napis, MAX), ret);
        for(i = 0; i < ret; i++)
            printf("%lc|", bufor[i]);
        printf("\n");
    }
}

When the code with gcc -o file file.c and run it, I always get 1 from mblen() . Why does it happen?

Everything else works perfectly, but mblen() does not.

I've tried to use LC_ALL, but nothing changed.

Answer 1

Because the first "c" in "coś żółtego" is only 1 byte

the mblen() function inspects at most n bytes of the multibyte string starting at s and extracts the next complete multibyte character .

Change to "żoś żółtego" and see what happens.