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  <section id="bytes-objects">
<span id="bytesobjects"></span><h1>Bytes Objects<a class="headerlink" href="#bytes-objects" title="Permalink to this headline">¶</a></h1>
<p>These functions raise <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> when expecting a bytes parameter and
called with a non-bytes parameter.</p>
<span class="target" id="index-0"></span><dl class="c type">
<dt class="sig sig-object c" id="c.PyBytesObject">
<span class="k"><span class="pre">type</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytesObject</span></span></span><a class="headerlink" href="#c.PyBytesObject" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>This subtype of <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyObject</span></code></a> represents a Python bytes object.</p>
</dd></dl>

<dl class="c var">
<dt class="sig sig-object c" id="c.PyBytes_Type">
<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><span class="n"><span class="pre">PyTypeObject</span></span></a><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_Type</span></span></span><a class="headerlink" href="#c.PyBytes_Type" title="Permalink to this definition">¶</a><br /></dt>
<dd><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>This instance of <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal notranslate"><span class="pre">PyTypeObject</span></code></a> represents the Python bytes type; it
is the same object as <a class="reference internal" href="../library/stdtypes.html#bytes" title="bytes"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytes</span></code></a> in the Python layer.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_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">PyBytes_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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_Check" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if the object <em>o</em> is a bytes object or an instance of a subtype
of the bytes type.  This function always succeeds.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_CheckExact">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_CheckExact</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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_CheckExact" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if the object <em>o</em> is a bytes object, but not an instance of a
subtype of the bytes type.  This function always succeeds.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_FromString">
<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">PyBytes_FromString</span></span></span><span class="sig-paren">(</span><span class="k"><span class="pre">const</span></span><span class="w"> </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">v</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_FromString" 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>Return a new bytes object with a copy of the string <em>v</em> as value on success,
and <code class="docutils literal notranslate"><span class="pre">NULL</span></code> on failure.  The parameter <em>v</em> must not be <code class="docutils literal notranslate"><span class="pre">NULL</span></code>; it will not be
checked.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_FromStringAndSize">
<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">PyBytes_FromStringAndSize</span></span></span><span class="sig-paren">(</span><span class="k"><span class="pre">const</span></span><span class="w"> </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">v</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">len</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_FromStringAndSize" 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>Return a new bytes object with a copy of the string <em>v</em> as value and length
<em>len</em> on success, and <code class="docutils literal notranslate"><span class="pre">NULL</span></code> on failure.  If <em>v</em> is <code class="docutils literal notranslate"><span class="pre">NULL</span></code>, the contents of
the bytes object are uninitialized.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_FromFormat">
<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">PyBytes_FromFormat</span></span></span><span class="sig-paren">(</span><span class="k"><span class="pre">const</span></span><span class="w"> </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">format</span></span>, <span class="p"><span class="pre">...</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_FromFormat" 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>Take a C <code class="xref c c-func docutils literal notranslate"><span class="pre">printf()</span></code>-style <em>format</em> string and a variable number of
arguments, calculate the size of the resulting Python bytes object and return
a bytes object with the values formatted into it.  The variable arguments
must be C types and must correspond exactly to the format characters in the
<em>format</em> string.  The following format characters are allowed:</p>
<table class="docutils align-default">
<colgroup>
<col style="width: 29%" />
<col style="width: 23%" />
<col style="width: 48%" />
</colgroup>
<thead>
<tr class="row-odd"><th class="head"><p>Format Characters</p></th>
<th class="head"><p>Type</p></th>
<th class="head"><p>Comment</p></th>
</tr>
</thead>
<tbody>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%%</span></code></p></td>
<td><p><em>n/a</em></p></td>
<td><p>The literal % character.</p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%c</span></code></p></td>
<td><p>int</p></td>
<td><p>A single byte,
represented as a C int.</p></td>
</tr>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%d</span></code></p></td>
<td><p>int</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%d&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id1">1</a></p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%u</span></code></p></td>
<td><p>unsigned int</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%u&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id2">1</a></p></td>
</tr>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%ld</span></code></p></td>
<td><p>long</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%ld&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id3">1</a></p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%lu</span></code></p></td>
<td><p>unsigned long</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%lu&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id4">1</a></p></td>
</tr>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%zd</span></code></p></td>
<td><p><a class="reference internal" href="intro.html#c.Py_ssize_t" title="Py_ssize_t"><code class="xref c c-type docutils literal notranslate"><span class="pre">Py_ssize_t</span></code></a></p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%zd&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id5">1</a></p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%zu</span></code></p></td>
<td><p>size_t</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%zu&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id6">1</a></p></td>
</tr>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%i</span></code></p></td>
<td><p>int</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%i&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id7">1</a></p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%x</span></code></p></td>
<td><p>int</p></td>
<td><p>Equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%x&quot;)</span></code>. <a class="footnote-reference brackets" href="#id9" id="id8">1</a></p></td>
</tr>
<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">%s</span></code></p></td>
<td><p>const char*</p></td>
<td><p>A null-terminated C character
array.</p></td>
</tr>
<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">%p</span></code></p></td>
<td><p>const void*</p></td>
<td><p>The hex representation of a C
pointer. Mostly equivalent to
<code class="docutils literal notranslate"><span class="pre">printf(&quot;%p&quot;)</span></code> except that
it is guaranteed to start with
the literal <code class="docutils literal notranslate"><span class="pre">0x</span></code> regardless
of what the platform’s
<code class="docutils literal notranslate"><span class="pre">printf</span></code> yields.</p></td>
</tr>
</tbody>
</table>
<p>An unrecognized format character causes all the rest of the format string to be
copied as-is to the result object, and any extra arguments discarded.</p>
<dl class="footnote brackets">
<dt class="label" id="id9"><span class="brackets">1</span><span class="fn-backref">(<a href="#id1">1</a>,<a href="#id2">2</a>,<a href="#id3">3</a>,<a href="#id4">4</a>,<a href="#id5">5</a>,<a href="#id6">6</a>,<a href="#id7">7</a>,<a href="#id8">8</a>)</span></dt>
<dd><p>For integer specifiers (d, u, ld, lu, zd, zu, i, x): the 0-conversion
flag has effect even when a precision is given.</p>
</dd>
</dl>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_FromFormatV">
<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">PyBytes_FromFormatV</span></span></span><span class="sig-paren">(</span><span class="k"><span class="pre">const</span></span><span class="w"> </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">format</span></span>, <span class="n"><span class="pre">va_list</span></span><span class="w"> </span><span class="n"><span class="pre">vargs</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_FromFormatV" 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>Identical to <a class="reference internal" href="#c.PyBytes_FromFormat" title="PyBytes_FromFormat"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBytes_FromFormat()</span></code></a> except that it takes exactly two
arguments.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_FromObject">
<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">PyBytes_FromObject</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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_FromObject" 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>Return the bytes representation of object <em>o</em> that implements the buffer
protocol.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_Size">
<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="sig-name descname"><span class="n"><span class="pre">PyBytes_Size</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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_Size" title="Permalink to this definition">¶</a><br /></dt>
<dd><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>Return the length of the bytes in bytes object <em>o</em>.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_GET_SIZE">
<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="sig-name descname"><span class="n"><span class="pre">PyBytes_GET_SIZE</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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_GET_SIZE" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Similar to <a class="reference internal" href="#c.PyBytes_Size" title="PyBytes_Size"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBytes_Size()</span></code></a>, but without error checking.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_AsString">
<span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_AsString</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">o</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_AsString" title="Permalink to this definition">¶</a><br /></dt>
<dd><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>Return a pointer to the contents of <em>o</em>.  The pointer
refers to the internal buffer of <em>o</em>, which consists of <code class="docutils literal notranslate"><span class="pre">len(o)</span> <span class="pre">+</span> <span class="pre">1</span></code>
bytes.  The last byte in the buffer is always null, regardless of
whether there are any other null bytes.  The data must not be
modified in any way, unless the object was just created using
<code class="docutils literal notranslate"><span class="pre">PyBytes_FromStringAndSize(NULL,</span> <span class="pre">size)</span></code>. It must not be deallocated.  If
<em>o</em> is not a bytes object at all, <a class="reference internal" href="#c.PyBytes_AsString" title="PyBytes_AsString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBytes_AsString()</span></code></a> returns <code class="docutils literal notranslate"><span class="pre">NULL</span></code>
and raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_AS_STRING">
<span class="kt"><span class="pre">char</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_AS_STRING</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">string</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_AS_STRING" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Similar to <a class="reference internal" href="#c.PyBytes_AsString" title="PyBytes_AsString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBytes_AsString()</span></code></a>, but without error checking.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_AsStringAndSize">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_AsStringAndSize</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">char</span></span><span class="w"> </span><span class="p"><span class="pre">*</span></span><span class="p"><span class="pre">*</span></span><span class="n"><span class="pre">buffer</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="p"><span class="pre">*</span></span><span class="n"><span class="pre">length</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_AsStringAndSize" title="Permalink to this definition">¶</a><br /></dt>
<dd><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>Return the null-terminated contents of the object <em>obj</em>
through the output variables <em>buffer</em> and <em>length</em>.</p>
<p>If <em>length</em> is <code class="docutils literal notranslate"><span class="pre">NULL</span></code>, the bytes object
may not contain embedded null bytes;
if it does, the function returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> and a <a class="reference internal" href="../library/exceptions.html#ValueError" title="ValueError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">ValueError</span></code></a> is raised.</p>
<p>The buffer refers to an internal buffer of <em>obj</em>, which includes an
additional null byte at the end (not counted in <em>length</em>).  The data
must not be modified in any way, unless the object was just created using
<code class="docutils literal notranslate"><span class="pre">PyBytes_FromStringAndSize(NULL,</span> <span class="pre">size)</span></code>.  It must not be deallocated.  If
<em>obj</em> is not a bytes object at all, <a class="reference internal" href="#c.PyBytes_AsStringAndSize" title="PyBytes_AsStringAndSize"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyBytes_AsStringAndSize()</span></code></a>
returns <code class="docutils literal notranslate"><span class="pre">-1</span></code> and raises <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a>.</p>
<div class="versionchanged">
<p><span class="versionmodified changed">Changed in version 3.5: </span>Previously, <a class="reference internal" href="../library/exceptions.html#TypeError" title="TypeError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">TypeError</span></code></a> was raised when embedded null bytes were
encountered in the bytes object.</p>
</div>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_Concat">
<span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_Concat</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="p"><span class="pre">*</span></span><span class="n"><span class="pre">bytes</span></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">newpart</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_Concat" title="Permalink to this definition">¶</a><br /></dt>
<dd><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 new bytes object in <em>*bytes</em> containing the contents of <em>newpart</em>
appended to <em>bytes</em>; the caller will own the new reference.  The reference to
the old value of <em>bytes</em> will be stolen.  If the new object cannot be
created, the old reference to <em>bytes</em> will still be discarded and the value
of <em>*bytes</em> will be set to <code class="docutils literal notranslate"><span class="pre">NULL</span></code>; the appropriate exception will be set.</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c.PyBytes_ConcatAndDel">
<span class="kt"><span class="pre">void</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyBytes_ConcatAndDel</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="p"><span class="pre">*</span></span><span class="n"><span class="pre">bytes</span></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">newpart</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyBytes_ConcatAndDel" title="Permalink to this definition">¶</a><br /></dt>
<dd><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 new bytes object in <em>*bytes</em> containing the contents of <em>newpart</em>
appended to <em>bytes</em>.  This version releases the <a class="reference internal" href="../glossary.html#term-strong-reference"><span class="xref std std-term">strong reference</span></a>
to <em>newpart</em> (i.e. decrements its reference count).</p>
</dd></dl>

<dl class="c function">
<dt class="sig sig-object c" id="c._PyBytes_Resize">
<span class="kt"><span class="pre">int</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">_PyBytes_Resize</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="p"><span class="pre">*</span></span><span class="n"><span class="pre">bytes</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">newsize</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c._PyBytes_Resize" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>A way to resize a bytes object even though it is “immutable”. Only use this
to build up a brand new bytes object; don’t use this if the bytes may already
be known in other parts of the code.  It is an error to call this function if
the refcount on the input bytes object is not one. Pass the address of an
existing bytes object as an lvalue (it may be written into), and the new size
desired.  On success, <em>*bytes</em> holds the resized bytes object and <code class="docutils literal notranslate"><span class="pre">0</span></code> is
returned; the address in <em>*bytes</em> may differ from its input value.  If the
reallocation fails, the original bytes object at <em>*bytes</em> is deallocated,
<em>*bytes</em> is set to <code class="docutils literal notranslate"><span class="pre">NULL</span></code>, <a class="reference internal" href="../library/exceptions.html#MemoryError" title="MemoryError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">MemoryError</span></code></a> is set, and <code class="docutils literal notranslate"><span class="pre">-1</span></code> is
returned.</p>
</dd></dl>

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