runtime/Lib/site-packages/Cython/Includes/cpython/memoryview.pxd

cdef extern from "Python.h":

    ###########################################################################
    # MemoryView Objects
    ###########################################################################
    # A memoryview object exposes the C level buffer interface as a Python
    # object which can then be passed around like any other object

    object PyMemoryView_FromObject(object obj)
    # Return value: New reference.
    # 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.

    object PyMemoryView_FromMemory(char *mem, Py_ssize_t size, int flags)
    # Return value: New reference.
    # Create a memoryview object using mem as the underlying buffer. flags can
    # be one of PyBUF_READ or PyBUF_WRITE.
    # New in version 3.3.

    object PyMemoryView_FromBuffer(Py_buffer *view)
    # Return value: New reference.
    # Create a memoryview object wrapping the given buffer structure view. For
    # simple byte buffers, PyMemoryView_FromMemory() is the preferred function.

    object PyMemoryView_GetContiguous(object obj,
                                      int buffertype,
                                      char order)
    # Return value: New reference.
    # 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.

    bint PyMemoryView_Check(object obj)
    # Return true if the object obj is a memoryview object. It is not currently
    # allowed to create subclasses of memoryview.

    Py_buffer *PyMemoryView_GET_BUFFER(object 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.

    Py_buffer *PyMemoryView_GET_BASE(object 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 PyMemoryView_FromMemory() or PyMemoryView_FromBuffer(). mview
    # must be a memoryview instance.