code: func memoryMap(path string) (*os.File, mmap.MMap, []uint32, error) {
  	file, err := os.OpenFile(path, os.O_RDONLY, 0644)
  	if err != nil {
  		return nil, nil, nil, err
  	}
  	mem, buffer, err := memoryMapFile(file, false)
  	if err != nil {
  		file.Close()
  		return nil, nil, nil, err
  	}
  	for i, magic := range dumpMagic {
  		if buffer[i] != magic {
  			mem.Unmap()
  			file.Close()
  			return nil, nil, nil, ErrInvalidDumpMagic
  		}
  	}
  	return file, mem, buffer[len(dumpMagic):], err
  }
docs: // memoryMap tries to memory map a file of uint32s for read only access.