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Byte Array Objects

Doc/c-api/bytearray.rst

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.. highlight:: c

.. _bytearrayobjects:

Byte Array Objects

.. index:: pair: object; bytearray

.. c:type:: PyByteArrayObject

This subtype of :c:type:PyObject represents a Python bytearray object.

.. c:var:: PyTypeObject PyByteArray_Type

This instance of :c:type:PyTypeObject represents the Python bytearray type; it is the same object as :class:bytearray in the Python layer.

Type check macros ^^^^^^^^^^^^^^^^^

.. c:function:: int PyByteArray_Check(PyObject *o)

Return true if the object o is a bytearray object or an instance of a subtype of the bytearray type. This function always succeeds.

.. c:function:: int PyByteArray_CheckExact(PyObject *o)

Return true if the object o is a bytearray object, but not an instance of a subtype of the bytearray type. This function always succeeds.

Direct API functions ^^^^^^^^^^^^^^^^^^^^

.. c:function:: PyObject* PyByteArray_FromObject(PyObject *o)

Return a new bytearray object from any object, o, that implements the :ref:buffer protocol <bufferobjects>.

On failure, return NULL with an exception set.

.. note:: If the object implements the buffer protocol, then the buffer must not be mutated while the bytearray object is being created.

.. c:function:: PyObject* PyByteArray_FromStringAndSize(const char *string, Py_ssize_t len)

Create a new bytearray object from string and its length, len.

On failure, return NULL with an exception set.

.. c:function:: PyObject* PyByteArray_Concat(PyObject *a, PyObject *b)

Concat bytearrays a and b and return a new bytearray with the result.

On failure, return NULL with an exception set.

.. note:: If the object implements the buffer protocol, then the buffer must not be mutated while the bytearray object is being created.

.. c:function:: Py_ssize_t PyByteArray_Size(PyObject *bytearray)

Return the size of bytearray after checking for a NULL pointer.

.. c:function:: char* PyByteArray_AsString(PyObject *bytearray)

Return the contents of bytearray as a char array after checking for a NULL pointer. The returned array always has an extra null byte appended.

.. note:: It is not thread-safe to mutate the bytearray object while using the returned char array.

.. c:function:: int PyByteArray_Resize(PyObject *bytearray, Py_ssize_t len)

Resize the internal buffer of bytearray to len. Failure is a -1 return with an exception set.

.. versionchanged:: 3.14 A negative len will now result in an exception being set and -1 returned.

Macros ^^^^^^

These macros trade safety for speed and they don't check pointers.

.. c:function:: char* PyByteArray_AS_STRING(PyObject *bytearray)

Similar to :c:func:PyByteArray_AsString, but without error checking.

.. note:: It is not thread-safe to mutate the bytearray object while using the returned char array.

.. c:function:: Py_ssize_t PyByteArray_GET_SIZE(PyObject *bytearray)

Similar to :c:func:PyByteArray_Size, but without error checking.