mirror of
https://github.com/python/cpython.git
synced 2025-11-03 19:34:08 +00:00
76 lines
2.5 KiB
ReStructuredText
76 lines
2.5 KiB
ReStructuredText
.. highlight:: c
|
|
|
|
.. _memoryview-objects:
|
|
|
|
.. index::
|
|
pair: object; memoryview
|
|
|
|
MemoryView objects
|
|
------------------
|
|
|
|
A :class:`memoryview` object exposes the C level :ref:`buffer interface
|
|
<bufferobjects>` as a Python object which can then be passed around like
|
|
any other object.
|
|
|
|
|
|
.. c:function:: PyObject *PyMemoryView_FromObject(PyObject *obj)
|
|
|
|
Create a memoryview object from an object that provides the buffer interface.
|
|
If *obj* supports writable buffer exports, the memoryview object will be
|
|
read/write, otherwise it may be either read-only or read/write at the
|
|
discretion of the exporter.
|
|
|
|
|
|
.. c:macro:: PyBUF_READ
|
|
|
|
Flag to request a readonly buffer.
|
|
|
|
|
|
.. c:macro:: PyBUF_WRITE
|
|
|
|
Flag to request a writable buffer.
|
|
|
|
|
|
.. c:function:: PyObject *PyMemoryView_FromMemory(char *mem, Py_ssize_t size, int flags)
|
|
|
|
Create a memoryview object using *mem* as the underlying buffer.
|
|
*flags* can be one of :c:macro:`PyBUF_READ` or :c:macro:`PyBUF_WRITE`.
|
|
|
|
.. versionadded:: 3.3
|
|
|
|
.. c:function:: PyObject *PyMemoryView_FromBuffer(const Py_buffer *view)
|
|
|
|
Create a memoryview object wrapping the given buffer structure *view*.
|
|
For simple byte buffers, :c:func:`PyMemoryView_FromMemory` is the preferred
|
|
function.
|
|
|
|
.. c:function:: PyObject *PyMemoryView_GetContiguous(PyObject *obj, int buffertype, char order)
|
|
|
|
Create a memoryview object to a :term:`contiguous` chunk of memory (in either
|
|
'C' or 'F'ortran *order*) from an object that defines the buffer
|
|
interface. If memory is contiguous, the memoryview object points to the
|
|
original memory. Otherwise, a copy is made and the memoryview points to a
|
|
new bytes object.
|
|
|
|
*buffertype* can be one of :c:macro:`PyBUF_READ` or :c:macro:`PyBUF_WRITE`.
|
|
|
|
|
|
.. c:function:: int PyMemoryView_Check(PyObject *obj)
|
|
|
|
Return true if the object *obj* is a memoryview object. It is not
|
|
currently allowed to create subclasses of :class:`memoryview`. This
|
|
function always succeeds.
|
|
|
|
|
|
.. c:function:: Py_buffer *PyMemoryView_GET_BUFFER(PyObject *mview)
|
|
|
|
Return a pointer to the memoryview's private copy of the exporter's buffer.
|
|
*mview* **must** be a memoryview instance; this macro doesn't check its type,
|
|
you must do it yourself or you will risk crashes.
|
|
|
|
.. c:function:: PyObject *PyMemoryView_GET_BASE(PyObject *mview)
|
|
|
|
Return either a pointer to the exporting object that the memoryview is based
|
|
on or ``NULL`` if the memoryview has been created by one of the functions
|
|
:c:func:`PyMemoryView_FromMemory` or :c:func:`PyMemoryView_FromBuffer`.
|
|
*mview* **must** be a memoryview instance.
|