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+.. highlightlang:: c
+
+.. _marshalling-utils:
+
+Data marshalling support
+========================
+
+These routines allow C code to work with serialized objects using the same data
+format as the :mod:`marshal` 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 (new in Python 2.4) shares interned strings in the file, and
+upon unmarshalling. *Py_MARSHAL_VERSION* indicates the current file format
+(currently 1).
+
+
+.. cfunction:: void PyMarshal_WriteLongToFile(long value, FILE *file, int version)
+
+   Marshal a :ctype:`long` integer, *value*, to *file*.  This will only write the
+   least-significant 32 bits of *value*; regardless of the size of the native
+   :ctype:`long` type.  *version* indicates the file format.
+
+
+.. cfunction:: void PyMarshal_WriteObjectToFile(PyObject *value, FILE *file, int version)
+
+   Marshal a Python object, *value*, to *file*.
+   *version* indicates the file format.
+
+
+.. cfunction:: PyObject* PyMarshal_WriteObjectToString(PyObject *value, int version)
+
+   Return a string object containing the marshalled representation of *value*.
+   *version* indicates the file format.
+
+
+The following functions allow marshalled values to be read back in.
+
+XXX What about error detection?  It appears that reading past the end of the
+file will always result in a negative numeric value (where that's relevant), but
+it's not clear that negative values won't be handled properly when there's no
+error.  What's the right way to tell? Should only non-negative values be written
+using these routines?
+
+
+.. cfunction:: long PyMarshal_ReadLongFromFile(FILE *file)
+
+   Return a C :ctype:`long` from the data stream in a :ctype:`FILE\*` opened for
+   reading.  Only a 32-bit value can be read in using this function, regardless of
+   the native size of :ctype:`long`.
+
+
+.. cfunction:: int PyMarshal_ReadShortFromFile(FILE *file)
+
+   Return a C :ctype:`short` from the data stream in a :ctype:`FILE\*` opened for
+   reading.  Only a 16-bit value can be read in using this function, regardless of
+   the native size of :ctype:`short`.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadObjectFromFile(FILE *file)
+
+   Return a Python object from the data stream in a :ctype:`FILE\*` opened for
+   reading.  On error, sets the appropriate exception (:exc:`EOFError` or
+   :exc:`TypeError`) and returns *NULL*.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadLastObjectFromFile(FILE *file)
+
+   Return a Python object from the data stream in a :ctype:`FILE\*` opened for
+   reading.  Unlike :cfunc:`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 (:exc:`EOFError` or
+   :exc:`TypeError`) and returns *NULL*.
+
+
+.. cfunction:: PyObject* PyMarshal_ReadObjectFromString(char *string, Py_ssize_t len)
+
+   Return a Python object from the data stream in a character buffer containing
+   *len* bytes pointed to by *string*.  On error, sets the appropriate exception
+   (:exc:`EOFError` or :exc:`TypeError`) and returns *NULL*.