C++ CEPH&x2B；Librados++；没有返回一致的结果

嘿，我正在尝试使用CEPH来存储一些数据，但是有一个问题，我通过librados++向CEPH写入数据和从CEPH读取数据是不同的

我有一个简单的例子：

#include <iostream>
#include <string>
#include <rados/librados.hpp>

int main(int argc, const char **argv)
{

    int ret = 0;

    /* Declare the cluster handle and required variables. */
    librados::Rados cluster;
    char cluster_name[] = "ceph";
    char user_name[] = "client.admin";
    uint64_t flags = 0;

    /* Initialize the cluster handle with the "ceph" cluster name and "client.admin" user */
    {
        ret = cluster.init2(user_name, cluster_name, flags);
        if (ret < 0)
        {
            std::cerr << "Couldn't initialize the cluster handle! error " << ret << std::endl;
            return EXIT_FAILURE;
        }
        else
        {
            std::cout << "Created a cluster handle." << std::endl;
        }
    }

    /* Read a Ceph configuration file to configure the cluster handle. */
    {
        ret = cluster.conf_read_file("/etc/ceph/ceph.conf");
        if (ret < 0)
        {
            std::cerr << "Couldn't read the Ceph configuration file! error " << ret << std::endl;
            return EXIT_FAILURE;
        }
        else
        {
            std::cout << "Read the Ceph configuration file." << std::endl;
        }
    }

    /* Read command line arguments */
    {
        ret = cluster.conf_parse_argv(argc, argv);
        if (ret < 0)
        {
            std::cerr << "Couldn't parse command line options! error " << ret << std::endl;
            return EXIT_FAILURE;
        }
        else
        {
            std::cout << "Parsed command line options." << std::endl;
        }
    }

    /* Connect to the cluster */
    {
        ret = cluster.connect();
        if (ret < 0)
        {
            std::cerr << "Couldn't connect to cluster! error " << ret
                    << std::endl;
            return EXIT_FAILURE;
        }
        else
        {
            std::cout << "Connected to the cluster." << std::endl;
        }
    }

    /* Continued from previous C++ example, where cluster handle and
     * connection are established. First declare an I/O Context.
     */

    librados::IoCtx io_ctx;
    const char *pool_name = "data";

    {
        ret = cluster.ioctx_create(pool_name, io_ctx);
        if (ret < 0)
        {
            std::cerr << "Couldn't set up ioctx! error " << ret << std::endl;
            exit(EXIT_FAILURE);
        }
        else
        {
            std::cout << "Created an ioctx for the pool." << std::endl;
        }

        librados::bufferlist bl;
        std::string hw = "hello world!";
        bl.append(hw.c_str());

        ret = io_ctx.write_full("hw", bl);

        librados::bufferlist rl;
        int read_len = hw.size();
        librados::AioCompletion* rc = librados::Rados::aio_create_completion();
        ret = io_ctx.aio_read("hw", rc, &rl, read_len, 0);
        rc->wait_for_complete();

        ret = rc->get_return_value();

        if (!(ret < 0))
        {
            auto out = std::string(rl.c_str());
            std::cout << out << std::endl;
        }
        else
        {
            std::cout << "da <expletive deleted>?" << std::endl;
        }

    }

    return 0;
}

#包括
#包括
#包括
int main（int argc，常量字符**argv）
{
int-ret=0；
/*声明集群句柄和必需的变量*/
librados:：Rados集群；
char cluster_name[]=“ceph”；
char user_name[]=“client.admin”；
uint64_t标志=0；
/*使用“ceph”集群名称和“client.admin”用户初始化集群句柄*/
{
ret=cluster.init2（用户名、集群名称、标志）；
如果（ret<0）
{
即使调用c_str（）函数，Ceph bufferlist结构实际上也不是以NULL结尾的。（很抱歉，设计不好！）

因此，当您调用bufferlist:：c_str（）并将其交给字符串构造函数时，它的长度将是任意的，直到它后面的第一个随机空字节为止。您可以通过获取长度并在构造字符串时显式设置来解决此问题。
@user4581301感谢您的编辑，并对这个顽皮的单词表示抱歉