如何在包含null的缓冲区中搜索子字符串？

#include<iostream>
#include<string>

int main() {
    char buffer[] = {'a', 'b', '\0', 'c', 'd', '\0', 'e', 'f'};
    std::string str(buffer, sizeof(buffer));

    // 替换null字符
    for (size_t i = 0; i < str.size(); ++i) {
        if (str[i] == '\0') {
            str[i] = ' ';
        }
    }

    // 搜索子字符串
    std::string substr = "cd";
    size_t pos = str.find(substr);
    if (pos != std::string::npos) {
        std::cout << "Substring found at position: "<< pos<< std::endl;
    } else {
        std::cout << "Substring not found"<< std::endl;
    }

    return 0;
}

#include<iostream>

int main() {
    char buffer[] = {'a', 'b', '\0', 'c', 'd', '\0', 'e', 'f'};
    const char* substr = "cd";
    const char* ptr = buffer;

    while (*ptr) {
        if (strncmp(ptr, substr, strlen(substr)) == 0) {
            std::cout << "Substring found at position: " << (ptr - buffer)<< std::endl;
            break;
        }
        ++ptr;
    }

    if (*ptr == '\0') {
        std::cout << "Substring not found"<< std::endl;
    }

    return 0;
}