Edit File: objbuffer.txt
.. highlightlang:: c .. _abstract-buffer: Old Buffer Protocol =================== This section describes the legacy buffer protocol, which has been introduced in Python 1.6. It is still supported but deprecated in the Python 2.x series. Python 3 introduces a new buffer protocol which fixes weaknesses and shortcomings of the protocol, and has been backported to Python 2.6. See :ref:`bufferobjects` for more information. .. c:function:: int PyObject_AsCharBuffer(PyObject *obj, const char **buffer, Py_ssize_t *buffer_len) Returns a pointer to a read-only memory location usable as character-based input. The *obj* argument must support the single-segment character buffer interface. On success, returns ``0``, sets *buffer* to the memory location and *buffer_len* to the buffer length. Returns ``-1`` and sets a :exc:`TypeError` on error. .. versionadded:: 1.6 .. versionchanged:: 2.5 This function used an :c:type:`int *` type for *buffer_len*. This might require changes in your code for properly supporting 64-bit systems. .. c:function:: int PyObject_AsReadBuffer(PyObject *obj, const void **buffer, Py_ssize_t *buffer_len) Returns a pointer to a read-only memory location containing arbitrary data. The *obj* argument must support the single-segment readable buffer interface. On success, returns ``0``, sets *buffer* to the memory location and *buffer_len* to the buffer length. Returns ``-1`` and sets a :exc:`TypeError` on error. .. versionadded:: 1.6 .. versionchanged:: 2.5 This function used an :c:type:`int *` type for *buffer_len*. This might require changes in your code for properly supporting 64-bit systems. .. c:function:: int PyObject_CheckReadBuffer(PyObject *o) Returns ``1`` if *o* supports the single-segment readable buffer interface. Otherwise returns ``0``. .. versionadded:: 2.2 .. c:function:: int PyObject_AsWriteBuffer(PyObject *obj, void **buffer, Py_ssize_t *buffer_len) Returns a pointer to a writeable memory location. The *obj* argument must support the single-segment, character buffer interface. On success, returns ``0``, sets *buffer* to the memory location and *buffer_len* to the buffer length. Returns ``-1`` and sets a :exc:`TypeError` on error. .. versionadded:: 1.6 .. versionchanged:: 2.5 This function used an :c:type:`int *` type for *buffer_len*. This might require changes in your code for properly supporting 64-bit systems.