数组-memcpy-越界

#include <stdio.h>
#include <string.h>
int main(void)
{
    char src[] = "12345";

    char dest[] = "1234";
    printf("destination before memcpy: %s\n", dest);
    memcpy(dest, src, strlen(src));
    printf("destination after memcpy: %s\n %d ", dest,strlen(dest));
    return 0;
    }
/***** result ******/
  /*
  destination before 1234
  destination after 1234512345

  10
  */

内存结构 [1] [2] [3] [4] [\0]       [1]  [2]  [3]  [4]  [5]  [\0]

                 dest                             src