c - 奇怪的 strstr 行为

Question

我正在尝试查找子字符串在字符串中的位置。

#include <string.h>
#include <stdio.h>

void find_str(char const* str, char const* substr) 
{
    char* pos = strstr(str, substr);
    if(pos) {
        printf("found the string '%s' in '%s' at position: %d\n", substr, str, pos - str);
    } else {
        printf("the string '%s' was not found in '%s'\n", substr, str);
    }
}

int main(int argc, char* argv[]) 
{
    char* str = "gdeasegrfdtyguhıjohhıhugfydsasdrfgthyjkjhghh";
    find_str(str, "hh");
    find_str("dhenhheme    kekekeke hhtttttttttttttttttttttttttttttttttttttttthhtttttttttttt", "hh");

    return 0;
}

输出:

found the string 'hh' in 'gdeasegrfdtyguhıjohhıhugfydsasdrfgthyjkjhghh' at position: 19

found the string 'hh' in 'dhenhheme kekekeke hhtttttttttttttttttttttttttttttttttttttttthhtttttttttttt' at position: 4

在第一个例子中它说它在位置 19。但是它不应该说 18 吗？因为在第二个示例中它说 4。它从子字符串的开头开始。

我很困惑。

Answer 1

字符 'ı' 不是 ASCII 字符，因此它可能占用两个字节。