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<H1><A NAME="SECTION008600000000000000000"></A><A NAME="abstract-buffer"></A>
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6.6 Buffer Protocol
</H1>
<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"><td><nobr>int <b><tt id='l2h-347' xml:id='l2h-347' class="cfunction">PyObject_AsCharBuffer</tt></b>(</nobr></td><td>PyObject *<var>obj</var>,
const char **<var>buffer</var>,
int *<var>buffer_len</var>)</td></tr></table></dt>
<dd>
Returns a pointer to a read-only memory location useable as character-
based input. The <var>obj</var> argument must support the single-segment
character buffer interface. On success, returns <code>0</code>, sets
<var>buffer</var> to the memory location and <var>buffer_len</var> to the buffer
length. Returns <code>-1</code> and sets a <tt class="exception">TypeError</tt> on error.
<span class="versionnote">New in version 1.6.</span>
</dd></dl>
<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"><td><nobr>int <b><tt id='l2h-348' xml:id='l2h-348' class="cfunction">PyObject_AsReadBuffer</tt></b>(</nobr></td><td>PyObject *<var>obj</var>,
const void **<var>buffer</var>,
int *<var>buffer_len</var>)</td></tr></table></dt>
<dd>
Returns a pointer to a read-only memory location containing
arbitrary data. The <var>obj</var> argument must support the
single-segment readable buffer interface. On success, returns
<code>0</code>, sets <var>buffer</var> to the memory location and <var>buffer_len</var>
to the buffer length. Returns <code>-1</code> and sets a
<tt class="exception">TypeError</tt> on error.
<span class="versionnote">New in version 1.6.</span>
</dd></dl>
<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"><td><nobr>int <b><tt id='l2h-349' xml:id='l2h-349' class="cfunction">PyObject_CheckReadBuffer</tt></b>(</nobr></td><td>PyObject *<var>o</var>)</td></tr></table></dt>
<dd>
Returns <code>1</code> if <var>o</var> supports the single-segment readable
buffer interface. Otherwise returns <code>0</code>.
<span class="versionnote">New in version 2.2.</span>
</dd></dl>
<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"><td><nobr>int <b><tt id='l2h-350' xml:id='l2h-350' class="cfunction">PyObject_AsWriteBuffer</tt></b>(</nobr></td><td>PyObject *<var>obj</var>,
void **<var>buffer</var>,
int *<var>buffer_len</var>)</td></tr></table></dt>
<dd>
Returns a pointer to a writeable memory location. The <var>obj</var>
argument must support the single-segment, character buffer
interface. On success, returns <code>0</code>, sets <var>buffer</var> to the
memory location and <var>buffer_len</var> to the buffer length. Returns
<code>-1</code> and sets a <tt class="exception">TypeError</tt> on error.
<span class="versionnote">New in version 1.6.</span>
</dd></dl>
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<span class="release-info">Release 2.4.3, documentation updated on 29 March 2006.</span>
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