Old Buffer Protocol

Obsolète depuis la version 3.0.

These functions were part of the « old buffer protocol » API in Python 2. In Python 3, this protocol doesn’t exist anymore but the functions are still exposed to ease porting 2.x code. They act as a compatibility wrapper around the new buffer protocol, but they don’t give you control over the lifetime of the resources acquired when a buffer is exported.

Therefore, it is recommended that you call PyObject_GetBuffer() (or the y* or w* format codes with the PyArg_ParseTuple() family of functions) to get a buffer view over an object, and PyBuffer_Release() when the buffer view can be released.

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 TypeError on error.

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 TypeError on error.

int PyObject_CheckReadBuffer(PyObject *o)

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

int PyObject_AsWriteBuffer(PyObject *obj, void **buffer, Py_ssize_t *buffer_len)

Returns a pointer to a writable 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 TypeError on error.