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If <em>obj</em> 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.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_FromMemory"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_FromMemory</span></span></span><span class="sig-paren">(</span><span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">mem</span></span>, <a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><span class="n"><span class="pre">Py_ssize_t</span></span></a><span class="w"> </span><span class="n"><span class="pre">size</span></span>, <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="n"><span class="pre">flags</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromMemory" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a> since version 3.7.</em><p>Create a memoryview object using <em>mem</em> as the underlying buffer. <em>flags</em> can be one of <code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_READ</span></code> or <code class="xref c c-macro docutils literal notranslate"><span class="pre">PyBUF_WRITE</span></code>.</p> <div class="versionadded"> <p><span class="versionmodified added">New in version 3.3.</span></p> </div> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_FromBuffer"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_FromBuffer</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><span class="n"><span class="pre">Py_buffer</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">view</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_FromBuffer" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="refcount">Return value: New reference.</em><p>Create a memoryview object wrapping the given buffer structure <em>view</em>. For simple byte buffers, <a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> is the preferred function.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_GetContiguous"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_GetContiguous</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">obj</span></span>, <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="n"><span class="pre">buffertype</span></span>, <span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="n"><span class="pre">order</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GetContiguous" title="Permalink to this definition">¶</a><br /></dt> <dd><em class="refcount">Return value: New reference.</em><em class="stableabi"> Part of the <a class="reference internal" href="stable.html#stable"><span class="std std-ref">Stable ABI</span></a>.</em><p>Create a memoryview object to a <a class="reference internal" href="../glossary.html#term-contiguous"><span class="xref std std-term">contiguous</span></a> chunk of memory (in either ‘C’ or ‘F’ortran <em>order</em>) 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.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_Check"> <span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_Check</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">obj</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_Check" title="Permalink to this definition">¶</a><br /></dt> <dd><p>Return true if the object <em>obj</em> is a memoryview object. It is not currently allowed to create subclasses of <a class="reference internal" href="../library/stdtypes.html#memoryview" title="memoryview"><code class="xref py py-class docutils literal notranslate"><span class="pre">memoryview</span></code></a>. This function always succeeds.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_GET_BUFFER"> <a class="reference internal" href="buffer.html#c.Py_buffer" title="Py_buffer"><span class="n"><span class="pre">Py_buffer</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_GET_BUFFER</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">mview</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BUFFER" title="Permalink to this definition">¶</a><br /></dt> <dd><p>Return a pointer to the memoryview’s private copy of the exporter’s buffer. <em>mview</em> <strong>must</strong> be a memoryview instance; this macro doesn’t check its type, you must do it yourself or you will risk crashes.</p> </dd></dl> <dl class="c function"> <dt class="sig sig-object c" id="c.PyMemoryView_GET_BASE"> <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyMemoryView_GET_BASE</span></span></span><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><span class="n"><span class="pre">PyObject</span></span></a><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">mview</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyMemoryView_GET_BASE" title="Permalink to this definition">¶</a><br /></dt> <dd><p>Return either a pointer to the exporting object that the memoryview is based on or <code class="docutils literal notranslate"><span class="pre">NULL</span></code> if the memoryview has been created by one of the functions <a class="reference internal" href="#c.PyMemoryView_FromMemory" title="PyMemoryView_FromMemory"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromMemory()</span></code></a> or <a class="reference internal" href="#c.PyMemoryView_FromBuffer" title="PyMemoryView_FromBuffer"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyMemoryView_FromBuffer()</span></code></a>. <em>mview</em> <strong>must</strong> be a memoryview instance.</p> </dd></dl> </section> <div class="clearer"></div> </div> </div> </div> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h4>Previous topic</h4> <p class="topless"><a href="slice.html" title="previous chapter">Slice Objects</a></p> <h4>Next topic</h4> <p class="topless"><a href="weakref.html" title="next chapter">Weak Reference Objects</a></p> <div role="note" aria-label="source link"> <h3>This Page</h3> <ul class="this-page-menu"> <li><a href="../bugs.html">Report a Bug</a></li> <li> <a href="https://github.com/python/cpython/blob/3.10/Doc/c-api/memoryview.rst" rel="nofollow">Show Source </a> </li> </ul> </div> </div> </div> <div class="clearer"></div> </div> <div class="related" role="navigation" aria-label="related navigation"> <h3>Navigation</h3> <ul> <li class="right" style="margin-right: 10px"> <a href="../genindex.html" title="General Index" >index</a></li> <li class="right" > <a href="../py-modindex.html" title="Python Module Index" >modules</a> |</li> <li class="right" > <a href="weakref.html" title="Weak Reference Objects" >next</a> |</li> <li class="right" > <a href="slice.html" title="Slice Objects" >previous</a> |</li> <li><img src="../_static/py.svg" alt="python logo" style="vertical-align: middle; 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