代码

#include <openssl/md5.h>#include <sstream>
#include <iomanip>
#include <iostream>void get_string_md5(const std::string& await_md5_string) {unsigned char md5[MD5_DIGEST_LENGTH];MD5(reinterpret_cast<unsigned const char*>(await_md5_string.c_str()),await_md5_string.size(),md5);std::ostringstream sout;sout << std::hex<<std::setfill('0');for(long long c:md5){sout << std::setw(2) << (long long )c;}std::cout << sout.str() << std::endl;
}

主函数

int main(){std::string backup_dir = "/home/gsc/Projects/3.txt";std::ifstream file(backup_dir);std::stringstream buffer;buffer << file.rdbuf();std::string str(buffer.str());std::cout << str;get_string_md5(str);return 0;
}