struct mallinfo info = mallinfo ();
  printf("arena = %d\n", info.arena);
  printf("ordblks = %d\n", info.ordblks);
  printf("smblks = %d\n", info.smblks);
  printf("hblks = %d\n", info.hblks);
  printf("hblkhd = %d\n", info.hblkhd);
  printf("usmblks = %d\n", info.usmblks);
  printf("fsmblks = %d\n", info.fsmblks);
  printf("uordblks = %d\n", info.uordblks);
  printf("fordblks = %d\n", info.fordblks);
  printf("keepcost = %d\n", info.keepcost);