### 导航 - [索引](../genindex.xhtml "总目录") - [模块](../py-modindex.xhtml "Python 模块索引") | - [下一页](arg.xhtml "语句解释及变量编译") | - [上一页](import.xhtml "导入模块") | -  - [Python](https://www.python.org/) » - zh\_CN 3.7.3 [文档](../index.xhtml) » - [Python/C API 参考手册](index.xhtml) » - [工具](utilities.xhtml) » - $('.inline-search').show(0); | # Data marshalling support These routines allow C code to work with serialized objects using the same data format as the [`marshal`](../library/marshal.xhtml#module-marshal "marshal: Convert Python objects to streams of bytes and back (with different constraints).") module. There are functions to write data into the serialization format, and additional functions that can be used to read the data back. Files used to store marshalled data must be opened in binary mode. Numeric values are stored with the least significant byte first. The module supports two versions of the data format: version 0 is the historical version, version 1 shares interned strings in the file, and upon unmarshalling. Version 2 uses a binary format for floating point numbers. *Py\_MARSHAL\_VERSION* indicates the current file format (currently 2). void `PyMarshal_WriteLongToFile`(long *value*, FILE *\*file*, int *version*)Marshal a `long` integer, *value*, to *file*. This will only write the least-significant 32 bits of *value*; regardless of the size of the native `long` type. *version* indicates the file format. void `PyMarshal_WriteObjectToFile`([PyObject](structures.xhtml#c.PyObject "PyObject") *\*value*, FILE *\*file*, int *version*)Marshal a Python object, *value*, to *file*. *version* indicates the file format. [PyObject](structures.xhtml#c.PyObject "PyObject")\* `PyMarshal_WriteObjectToString`([PyObject](structures.xhtml#c.PyObject "PyObject") *\*value*, int *version*)*Return value: New reference.*Return a bytes object containing the marshalled representation of *value*. *version* indicates the file format. The following functions allow marshalled values to be read back in. long `PyMarshal_ReadLongFromFile`(FILE *\*file*)Return a C `long` from the data stream in a `FILE*` opened for reading. Only a 32-bit value can be read in using this function, regardless of the native size of `long`. On error, sets the appropriate exception ([`EOFError`](../library/exceptions.xhtml#EOFError "EOFError")) and returns `-1`. int `PyMarshal_ReadShortFromFile`(FILE *\*file*)Return a C `short` from the data stream in a `FILE*` opened for reading. Only a 16-bit value can be read in using this function, regardless of the native size of `short`. On error, sets the appropriate exception ([`EOFError`](../library/exceptions.xhtml#EOFError "EOFError")) and returns `-1`. [PyObject](structures.xhtml#c.PyObject "PyObject")\* `PyMarshal_ReadObjectFromFile`(FILE *\*file*)*Return value: New reference.*Return a Python object from the data stream in a `FILE*` opened for reading. On error, sets the appropriate exception ([`EOFError`](../library/exceptions.xhtml#EOFError "EOFError"), [`ValueError`](../library/exceptions.xhtml#ValueError "ValueError")or [`TypeError`](../library/exceptions.xhtml#TypeError "TypeError")) and returns *NULL*. [PyObject](structures.xhtml#c.PyObject "PyObject")\* `PyMarshal_ReadLastObjectFromFile`(FILE *\*file*)*Return value: New reference.*Return a Python object from the data stream in a `FILE*` opened for reading. Unlike [`PyMarshal_ReadObjectFromFile()`](#c.PyMarshal_ReadObjectFromFile "PyMarshal_ReadObjectFromFile"), this function assumes that no further objects will be read from the file, allowing it to aggressively load file data into memory so that the de-serialization can operate from data in memory rather than reading a byte at a time from the file. Only use these variant if you are certain that you won't be reading anything else from the file. On error, sets the appropriate exception ([`EOFError`](../library/exceptions.xhtml#EOFError "EOFError"), [`ValueError`](../library/exceptions.xhtml#ValueError "ValueError")or [`TypeError`](../library/exceptions.xhtml#TypeError "TypeError")) and returns *NULL*. [PyObject](structures.xhtml#c.PyObject "PyObject")\* `PyMarshal_ReadObjectFromString`(const char *\*data*, Py\_ssize\_t *len*)*Return value: New reference.*Return a Python object from the data stream in a byte buffer containing *len* bytes pointed to by *data*. On error, sets the appropriate exception ([`EOFError`](../library/exceptions.xhtml#EOFError "EOFError"), [`ValueError`](../library/exceptions.xhtml#ValueError "ValueError")or [`TypeError`](../library/exceptions.xhtml#TypeError "TypeError")) and returns *NULL*. ### 导航 - [索引](../genindex.xhtml "总目录") - [模块](../py-modindex.xhtml "Python 模块索引") | - [下一页](arg.xhtml "语句解释及变量编译") | - [上一页](import.xhtml "导入模块") | -  - [Python](https://www.python.org/) » - zh\_CN 3.7.3 [文档](../index.xhtml) » - [Python/C API 参考手册](index.xhtml) » - [工具](utilities.xhtml) » - $('.inline-search').show(0); | © [版权所有](../copyright.xhtml) 2001-2019, Python Software Foundation. Python 软件基金会是一个非盈利组织。 [请捐助。](https://www.python.org/psf/donations/) 最后更新于 5月 21, 2019. [发现了问题](../bugs.xhtml)？ 使用[Sphinx](http://sphinx.pocoo.org/)1.8.4 创建。