#define _GNU_SOURCE
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <inttypes.h>

int main(void)
{
        struct {
                struct file_handle fh;
                uint64_t cgroup_id;
        } handle;
        int mount_id;

        name_to_handle_at(AT_FDCWD, "/", &handle.fh, &mount_id, 0);
        return 0;
}