symbian-qemu-0.9.1-12/python-2.6.1/Doc/c-api/objbuffer.rst
author johnathan.white@2718R8BGH51.accenture.com
Mon, 08 Mar 2010 18:45:03 +0000
changeset 46 b6935a90ca64
parent 1 2fb8b9db1c86
permissions -rw-r--r--
Modify framebuffer and NGA framebuffer to read screen size from board model dtb file. Optimise memory usuage of frame buffer Add example minigui application with hooks to profiler (which writes results to S:\). Modified NGA framebuffer to run its own dfc queue at high priority

.. highlightlang:: c

.. _abstract-buffer:

Buffer Protocol
===============


.. cfunction:: 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


.. cfunction:: 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


.. cfunction:: int PyObject_CheckReadBuffer(PyObject *o)

   Returns ``1`` if *o* supports the single-segment readable buffer interface.
   Otherwise returns ``0``.

   .. versionadded:: 2.2


.. cfunction:: 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