cpython/Doc/c-api/memoryview.rst

53 lines
1.8 KiB
ReStructuredText

.. highlightlang:: c
.. _memoryview-objects:
.. index::
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
readable and writable, otherwise it will be read-only.
.. c:function:: PyObject *PyMemoryView_FromBuffer(Py_buffer *view)
Create a memoryview object wrapping the given buffer structure *view*.
The memoryview object then owns the buffer represented by *view*, which
means you shouldn't try to call :c:func:`PyBuffer_Release` yourself: it
will be done on deallocation of the memoryview object.
.. c:function:: PyObject *PyMemoryView_GetContiguous(PyObject *obj, int buffertype, char order)
Create a memoryview object to a 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.
.. 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`.
.. c:function:: Py_buffer *PyMemoryView_GET_BUFFER(PyObject *obj)
Return a pointer to the buffer structure wrapped by the given
memoryview object. The object **must** be a memoryview instance;
this macro doesn't check its type, you must do it yourself or you
will risk crashes.