C：从字符数组复制到int

  // Works
  int fnamesize=0;
  fnamesize=message[0]<<24;
  fnamesize+=message[1]<<16;
  fnamesize+=message[2]<<8;
  fnamesize+=message[3];

  // Doesn't work
  int fsize;
  memcpy(&fsize,message,sizeof(int));
  // Works
  int fnamesize=0;
  fnamesize=messa