資料 marshal 的支援¶
These routines allow C code to work with serialized objects using the same
data format as the 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 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.
This function can fail, in which case it sets the error indicator. Use
PyErr_Occurred()
to check for that.
-
void PyMarshal_WriteObjectToFile(PyObject *value, FILE *file, int version)¶
Marshal a Python object, value, to file. version indicates the file format.
This function can fail, in which case it sets the error indicator. Use
PyErr_Occurred()
to check for that.
-
PyObject *PyMarshal_WriteObjectToString(PyObject *value, int version)¶
- 回傳值:新的參照。
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
) 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
) and returns-1
.
-
PyObject *PyMarshal_ReadObjectFromFile(FILE *file)¶
- 回傳值:新的參照。
Return a Python object from the data stream in a FILE* opened for reading.
On error, sets the appropriate exception (
EOFError
,ValueError
orTypeError
) and returnsNULL
.
-
PyObject *PyMarshal_ReadLastObjectFromFile(FILE *file)¶
- 回傳值:新的參照。
Return a Python object from the data stream in a FILE* opened for reading. Unlike
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
,ValueError
orTypeError
) and returnsNULL
.
-
PyObject *PyMarshal_ReadObjectFromString(const char *data, Py_ssize_t len)¶
- 回傳值:新的參照。
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
,ValueError
orTypeError
) and returnsNULL
.