mirror of
https://github.com/python/cpython.git
synced 2025-11-04 03:44:55 +00:00
71 lines
2.6 KiB
ReStructuredText
71 lines
2.6 KiB
ReStructuredText
.. highlight:: c
|
|
|
|
.. _allocating-objects:
|
|
|
|
Allocating Objects on the Heap
|
|
==============================
|
|
|
|
|
|
.. c:function:: PyObject* _PyObject_New(PyTypeObject *type)
|
|
|
|
|
|
.. c:function:: PyVarObject* _PyObject_NewVar(PyTypeObject *type, Py_ssize_t size)
|
|
|
|
|
|
.. c:function:: PyObject* PyObject_Init(PyObject *op, PyTypeObject *type)
|
|
|
|
Initialize a newly-allocated object *op* with its type and initial
|
|
reference. Returns the initialized object. If *type* indicates that the
|
|
object participates in the cyclic garbage detector, it is added to the
|
|
detector's set of observed objects. Other fields of the object are not
|
|
affected.
|
|
|
|
|
|
.. c:function:: PyVarObject* PyObject_InitVar(PyVarObject *op, PyTypeObject *type, Py_ssize_t size)
|
|
|
|
This does everything :c:func:`PyObject_Init` does, and also initializes the
|
|
length information for a variable-size object.
|
|
|
|
|
|
.. c:function:: TYPE* PyObject_New(TYPE, PyTypeObject *type)
|
|
|
|
Allocate a new Python object using the C structure type *TYPE* and the
|
|
Python type object *type*. Fields not defined by the Python object header
|
|
are not initialized; the object's reference count will be one. The size of
|
|
the memory allocation is determined from the :c:member:`~PyTypeObject.tp_basicsize` field of
|
|
the type object.
|
|
|
|
|
|
.. c:function:: TYPE* PyObject_NewVar(TYPE, PyTypeObject *type, Py_ssize_t size)
|
|
|
|
Allocate a new Python object using the C structure type *TYPE* and the
|
|
Python type object *type*. Fields not defined by the Python object header
|
|
are not initialized. The allocated memory allows for the *TYPE* structure
|
|
plus *size* fields of the size given by the :c:member:`~PyTypeObject.tp_itemsize` field of
|
|
*type*. This is useful for implementing objects like tuples, which are
|
|
able to determine their size at construction time. Embedding the array of
|
|
fields into the same allocation decreases the number of allocations,
|
|
improving the memory management efficiency.
|
|
|
|
|
|
.. c:function:: void PyObject_Del(void *op)
|
|
|
|
Releases memory allocated to an object using :c:func:`PyObject_New` or
|
|
:c:func:`PyObject_NewVar`. This is normally called from the
|
|
:c:member:`~PyTypeObject.tp_dealloc` handler specified in the object's type. The fields of
|
|
the object should not be accessed after this call as the memory is no
|
|
longer a valid Python object.
|
|
|
|
|
|
.. c:var:: PyObject _Py_NoneStruct
|
|
|
|
Object which is visible in Python as ``None``. This should only be accessed
|
|
using the :c:macro:`Py_None` macro, which evaluates to a pointer to this
|
|
object.
|
|
|
|
|
|
.. seealso::
|
|
|
|
:c:func:`PyModule_Create`
|
|
To allocate and create extension modules.
|
|
|