io.py 文件源码

def open_compressed(filename, open_flag='r', compression_type='bz2'):
  """Opens a compressed HDF5File with the given opening flags.
  For the 'r' flag, the given compressed file will be extracted to a local space.
  For 'w', an empty HDF5File is created.
  In any case, the opened HDF5File is returned, which needs to be closed using the close_compressed() function.
  """
  # create temporary HDF5 file name
  hdf5_file_name = tempfile.mkstemp('.hdf5', 'bob_')[1]

  if open_flag == 'r':
    # extract the HDF5 file from the given file name into a temporary file name
    tar = tarfile.open(filename, mode="r:" + compression_type)
    memory_file = tar.extractfile(tar.next())
    real_file = open(hdf5_file_name, 'wb')
    real_file.write(memory_file.read())
    del memory_file
    real_file.close()
    tar.close()

  return bob.io.base.HDF5File(hdf5_file_name, open_flag)