# `marshal` — Internal Python object serialization

This module contains functions that can read and write Python values in a binary format. The format is specific to Python, but independent of machine architecture issues (e.g., you can write a Python value to a file on a PC, transport the file to a Sun, and read it back there). Details of the format are undocumented on purpose; it may change between Python versions (although it rarely does). [1]

This is not a general “persistence” module. For general persistence and transfer of Python objects through RPC calls, see the modules `pickle` and `shelve`. The `marshal` module exists mainly to support reading and writing the “pseudo-compiled” code for Python modules of `.pyc` files. Therefore, the Python maintainers reserve the right to modify the marshal format in backward incompatible ways should the need arise. If you’re serializing and de-serializing Python objects, use the `pickle` module instead – the performance is comparable, version independence is guaranteed, and pickle supports a substantially wider range of objects than marshal.

경고

`marshal` 모듈은 잘못되었거나 악의적으로 구성된 데이터에 대해 보안성을 갖추려는 것이 아닙니다. 신뢰할 수 없거나 인증되지 않은 출처에서 받은 데이터를 역 마샬 하지 마십시오.

Not all Python object types are supported; in general, only objects whose value is independent from a particular invocation of Python can be written and read by this module. The following types are supported: booleans, integers, floating point numbers, complex numbers, strings, bytes, bytearrays, tuples, lists, sets, frozensets, dictionaries, and code objects, where it should be understood that tuples, lists, sets, frozensets and dictionaries are only supported as long as the values contained therein are themselves supported. The singletons `None`, `Ellipsis` and `StopIteration` can also be marshalled and unmarshalled. For format version lower than 3, recursive lists, sets and dictionaries cannot be written (see below).

파일을 읽고 쓰는 함수는 물론 바이트열류 객체에서 작동하는 함수도 있습니다.

모듈은 다음 함수를 정의합니다:

marshal.dump(value, file[, version])

  열린 파일에 값을 기록합니다. value는 지원되는 형이어야 합니다. 파일은 쓰기 가능한 바이너리 파일 이어야 합니다.

  If the value has (or contains an object that has) an unsupported type, a `ValueError` exception is raised — but garbage data will also be written to the file. The object will not be properly read back by `load()`.

  version 인자는 `dump`가 사용해야 하는 데이터 형식을 나타냅니다 (아래를 참조하십시오).

  Raises an auditing event `marshal.dumps` with arguments `value`, `version`.

marshal.load(file)

  Read one value from the open file and return it. If no valid value is read (e.g. because the data has a different Python version’s incompatible marshal format), raise `EOFError`, `ValueError` or `TypeError`. The file must be a readable binary file.

  Raises an auditing event `marshal.load` with no arguments.

  참고

  지원하지 않는 형을 포함하는 객체가 `dump()`로 마샬 되었으면, `load()`는 역 마샬이 불가능한 형을 `None`으로 치환합니다.

  버전 3.10에서 변경: This call used to raise a `code.__new__` audit event for each code object. Now it raises a single `marshal.load` event for the entire load operation.

marshal.dumps(value[, version])

  Return the bytes object that would be written to a file by `dump(value, file)`. The value must be a supported type. Raise a `ValueError` exception if value has (or contains an object that has) an unsupported type.

  version 인자는 `dumps`가 사용해야 하는 데이터 형식을 나타냅니다 (아래를 참조하십시오).

  Raises an auditing event `marshal.dumps` with arguments `value`, `version`.

marshal.loads(bytes)

  Convert the bytes-like object to a value. If no valid value is found, raise `EOFError`, `ValueError` or `TypeError`. Extra bytes in the input are ignored.

  Raises an auditing event `marshal.loads` with argument `bytes`.

  버전 3.10에서 변경: This call used to raise a `code.__new__` audit event for each code object. Now it raises a single `marshal.loads` event for the entire load operation.

또한, 다음 상수가 정의됩니다:

marshal.version

  Indicates the format that the module uses. Version 0 is the historical format, version 1 shares interned strings and version 2 uses a binary format for floating point numbers. Version 3 adds support for object instancing and recursion. The current version is 4.

각주

[1]

이 모듈의 이름은 (다른 것 중에서도) Modula-3의 설계자가 사용하는 약간의 용어에서 유래합니다. 이들은 자급적(self-contained) 형식으로 데이터를 전달하는 데 “마샬링(marshalling)”이라는 용어를 사용합니다. 엄밀히 말하면, “마샬”은 내부의 어떤 데이터를 외부 형식(예를 들어 RPC 버퍼에)으로 변환하는 것을, “역 마샬”은 그 반대 절차를 뜻합니다.