docs: public void dump_disk_memory(Writer out)
      throws IOException
      {
          long block_ptr;
          long cache_end;
  
          long magic;
          int size;
          long tail;
  
          out.write("Information stored on disk\n");
          seek(STARTOFDATA_LOCATION);
          magic = readLong();
          out.write("File magic number: " + magic + "\n");
          seek(TAIL_DPTR);
          tail = readLong();
          out.write("Tail on disk: " + tail + "\n");
          cache_end = readLong();
          out.write("End of cached free list info: " + cache_end + "\n");
          size = readInt();
          out.write("First quick size: " + size + "\n");
          size = readInt();
          out.write("Last quick size: " + size + "\n");
          size = readInt();
          out.write("Grain size: " + size + "\n");
          size = readInt();
          out.write("Acceptable waste: " + size + "\n");
          block_ptr = FIRST_TAIL;
          while (block_ptr < tail) {
              seek(block_ptr);
              size = readInt();
              out.write(block_ptr + ", " + size + "\n");
              block_ptr += abs(size);
          };
          out.write("\n\n");
      }