| .. highlightlang:: c | 
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 | .. _abstract-buffer: | 
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 | Buffer Protocol | 
 | =============== | 
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 | .. cfunction:: int PyObject_AsCharBuffer(PyObject *obj, const char **buffer, Py_ssize_t *buffer_len) | 
 |  | 
 |    Returns a pointer to a read-only memory location usable as character-based | 
 |    input.  The *obj* argument must support the single-segment character buffer | 
 |    interface.  On success, returns ``0``, sets *buffer* to the memory location | 
 |    and *buffer_len* to the buffer length.  Returns ``-1`` and sets a | 
 |    :exc:`TypeError` on error. | 
 |  | 
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 | .. cfunction:: int PyObject_AsReadBuffer(PyObject *obj, const void **buffer, Py_ssize_t *buffer_len) | 
 |  | 
 |    Returns a pointer to a read-only memory location containing arbitrary data. | 
 |    The *obj* argument must support the single-segment readable buffer | 
 |    interface.  On success, returns ``0``, sets *buffer* to the memory location | 
 |    and *buffer_len* to the buffer length.  Returns ``-1`` and sets a | 
 |    :exc:`TypeError` on error. | 
 |  | 
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 | .. cfunction:: int PyObject_CheckReadBuffer(PyObject *o) | 
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 |    Returns ``1`` if *o* supports the single-segment readable buffer interface. | 
 |    Otherwise returns ``0``. | 
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 | .. cfunction:: int PyObject_AsWriteBuffer(PyObject *obj, void **buffer, Py_ssize_t *buffer_len) | 
 |  | 
 |    Returns a pointer to a writable memory location.  The *obj* argument must | 
 |    support the single-segment, character buffer interface.  On success, | 
 |    returns ``0``, sets *buffer* to the memory location and *buffer_len* to the | 
 |    buffer length.  Returns ``-1`` and sets a :exc:`TypeError` on error. | 
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