奇怪的strstr行为

Question

我正在尝试在字符串中找到子字符串的位置.

#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 = "gdeasegrfdtyguh?johh?hugfydsasdrfgthyjkjhghh";
    find_str(str, "hh");
    find_str("dhenhheme    kekekeke hhtttttttttttttttttttttttttttttttttttttttthhtttttttttttt", "hh");

    return 0;
}

输出:

在'gdeasegrfdtyguhıjohhıhugfydsasdrfgthyjkjhghh'中找到了字符串'hh',位置:19

在'dhenhheme kekekeke hhttttttttttttttttttttttttttttttttttttttttttttttttthtttttttttttttt'中找到字符串'hh',位置:4

在第一个例子中,它表示它处于第19位.但是它不应该说是18吗？因为在第二个例子中它表示4.它从子串的开头开始.

我糊涂了.

Answer 1

该字符'?'不是ASCII字符,因此可能占用两个字节.