File: //usr/share/doc/python3-all/html/c-api/bytearray.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="generator" content="Docutils 0.17.1: http://docutils.sourceforge.net/" />
<title>Byte Array Objects — Python 3.10.12 documentation</title><meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" type="text/css" href="../_static/pygments.css" />
<link rel="stylesheet" type="text/css" href="../_static/pydoctheme.css?2022.1" />
<script data-url_root="../" id="documentation_options" src="../_static/documentation_options.js"></script>
<script src="../_static/jquery.js"></script>
<script src="../_static/underscore.js"></script>
<script src="../_static/doctools.js"></script>
<script src="../_static/sidebar.js"></script>
<link rel="search" type="application/opensearchdescription+xml"
title="Search within Python 3.10.12 documentation"
href="../_static/opensearch.xml"/>
<link rel="author" title="About these documents" href="../about.html" />
<link rel="index" title="Index" href="../genindex.html" />
<link rel="search" title="Search" href="../search.html" />
<link rel="copyright" title="Copyright" href="../copyright.html" />
<link rel="next" title="Unicode Objects and Codecs" href="unicode.html" />
<link rel="prev" title="Bytes Objects" href="bytes.html" />
<link rel="canonical" href="file:///usr/share/doc/python3.10/html/c-api/bytearray.html" />
<style>
@media only screen {
table.full-width-table {
width: 100%;
}
}
</style>
<link rel="shortcut icon" type="image/png" href="../_static/py.svg" />
<script type="text/javascript" src="../_static/copybutton.js"></script>
<script type="text/javascript" src="../_static/menu.js"></script>
</head>
<body>
<div class="mobile-nav">
<input type="checkbox" id="menuToggler" class="toggler__input" aria-controls="navigation"
aria-pressed="false" aria-expanded="false" role="button" aria-label="Menu" />
<label for="menuToggler" class="toggler__label">
<span></span>
</label>
<nav class="nav-content" role="navigation">
<a href="https://www.python.org/" class="nav-logo">
<img src="../_static/py.svg" alt="Logo"/>
</a>
<div class="version_switcher_placeholder"></div>
<form role="search" class="search" action="../search.html" method="get">
<svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24" class="search-icon">
<path fill-rule="nonzero"
d="M15.5 14h-.79l-.28-.27a6.5 6.5 0 001.48-5.34c-.47-2.78-2.79-5-5.59-5.34a6.505 6.505 0 00-7.27 7.27c.34 2.8 2.56 5.12 5.34 5.59a6.5 6.5 0 005.34-1.48l.27.28v.79l4.25 4.25c.41.41 1.08.41 1.49 0 .41-.41.41-1.08 0-1.49L15.5 14zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z" fill="#444"></path>
</svg>
<input type="text" name="q" aria-label="Quick search"/>
<input type="submit" value="Go"/>
</form>
</nav>
<div class="menu-wrapper">
<nav class="menu" role="navigation" aria-label="main navigation">
<div class="language_switcher_placeholder"></div>
<h3><a href="../contents.html">Table of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">Byte Array Objects</a><ul>
<li><a class="reference internal" href="#type-check-macros">Type check macros</a></li>
<li><a class="reference internal" href="#direct-api-functions">Direct API functions</a></li>
<li><a class="reference internal" href="#macros">Macros</a></li>
</ul>
</li>
</ul>
<h4>Previous topic</h4>
<p class="topless"><a href="bytes.html"
title="previous chapter">Bytes Objects</a></p>
<h4>Next topic</h4>
<p class="topless"><a href="unicode.html"
title="next chapter">Unicode Objects and Codecs</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/bytearray.rst"
rel="nofollow">Show Source
</a>
</li>
</ul>
</div>
</nav>
</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"
accesskey="I">index</a></li>
<li class="right" >
<a href="../py-modindex.html" title="Python Module Index"
>modules</a> |</li>
<li class="right" >
<a href="unicode.html" title="Unicode Objects and Codecs"
accesskey="N">next</a> |</li>
<li class="right" >
<a href="bytes.html" title="Bytes Objects"
accesskey="P">previous</a> |</li>
<li><img src="../_static/py.svg" alt="python logo" style="vertical-align: middle; margin-top: -1px"/></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li class="switchers">
<div class="language_switcher_placeholder"></div>
<div class="version_switcher_placeholder"></div>
</li>
<li>
</li>
<li id="cpython-language-and-version">
<a href="../index.html">3.10.12 Documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li>
<li class="nav-item nav-item-2"><a href="concrete.html" accesskey="U">Concrete Objects Layer</a> »</li>
<li class="nav-item nav-item-this"><a href="">Byte Array Objects</a></li>
<li class="right">
<div class="inline-search" role="search">
<form class="inline-search" action="../search.html" method="get">
<input placeholder="Quick search" aria-label="Quick search" type="text" name="q" />
<input type="submit" value="Go" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
|
</li>
</ul>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<section id="byte-array-objects">
<span id="bytearrayobjects"></span><h1>Byte Array Objects<a class="headerlink" href="#byte-array-objects" title="Permalink to this headline">¶</a></h1>
<span class="target" id="index-0"></span><dl class="c type">
<dt class="sig sig-object c" id="c.PyByteArrayObject">
<span class="k"><span class="pre">type</span></span><span class="w"> </span><span class="sig-name descname"><span class="n"><span class="pre">PyByteArrayObject</span></span></span><a class="headerlink" href="#c.PyByteArrayObject" 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 bytearray object.</p>
</dd></dl>
<dl class="c var">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_Type</span></span></span><a class="headerlink" href="#c.PyByteArray_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 bytearray type;
it is the same object as <a class="reference internal" href="../library/stdtypes.html#bytearray" title="bytearray"><code class="xref py py-class docutils literal notranslate"><span class="pre">bytearray</span></code></a> in the Python layer.</p>
</dd></dl>
<section id="type-check-macros">
<h2>Type check macros<a class="headerlink" href="#type-check-macros" title="Permalink to this headline">¶</a></h2>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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.PyByteArray_Check" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if the object <em>o</em> is a bytearray object or an instance of a
subtype of the bytearray type. This function always succeeds.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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.PyByteArray_CheckExact" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Return true if the object <em>o</em> is a bytearray object, but not an instance of a
subtype of the bytearray type. This function always succeeds.</p>
</dd></dl>
</section>
<section id="direct-api-functions">
<h2>Direct API functions<a class="headerlink" href="#direct-api-functions" title="Permalink to this headline">¶</a></h2>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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.PyByteArray_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 a new bytearray object from any object, <em>o</em>, that implements the
<a class="reference internal" href="buffer.html#bufferobjects"><span class="std std-ref">buffer protocol</span></a>.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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">string</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.PyByteArray_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>Create a new bytearray object from <em>string</em> and its length, <em>len</em>. On
failure, <code class="docutils literal notranslate"><span class="pre">NULL</span></code> is returned.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_Concat">
<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">PyByteArray_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="n"><span class="pre">a</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">b</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyByteArray_Concat" 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>Concat bytearrays <em>a</em> and <em>b</em> and return a new bytearray with the result.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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">bytearray</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyByteArray_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 size of <em>bytearray</em> after checking for a <code class="docutils literal notranslate"><span class="pre">NULL</span></code> pointer.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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">bytearray</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyByteArray_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 the contents of <em>bytearray</em> as a char array after checking for a
<code class="docutils literal notranslate"><span class="pre">NULL</span></code> pointer. The returned array always has an extra
null byte appended.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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="n"><span class="pre">bytearray</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.PyByteArray_Resize" 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>Resize the internal buffer of <em>bytearray</em> to <em>len</em>.</p>
</dd></dl>
</section>
<section id="macros">
<h2>Macros<a class="headerlink" href="#macros" title="Permalink to this headline">¶</a></h2>
<p>These macros trade safety for speed and they don’t check pointers.</p>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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">bytearray</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyByteArray_AS_STRING" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Macro version of <a class="reference internal" href="#c.PyByteArray_AsString" title="PyByteArray_AsString"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyByteArray_AsString()</span></code></a>.</p>
</dd></dl>
<dl class="c function">
<dt class="sig sig-object c" id="c.PyByteArray_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">PyByteArray_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">bytearray</span></span><span class="sig-paren">)</span><a class="headerlink" href="#c.PyByteArray_GET_SIZE" title="Permalink to this definition">¶</a><br /></dt>
<dd><p>Macro version of <a class="reference internal" href="#c.PyByteArray_Size" title="PyByteArray_Size"><code class="xref c c-func docutils literal notranslate"><span class="pre">PyByteArray_Size()</span></code></a>.</p>
</dd></dl>
</section>
</section>
<div class="clearer"></div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
<div class="sphinxsidebarwrapper">
<h3><a href="../contents.html">Table of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">Byte Array Objects</a><ul>
<li><a class="reference internal" href="#type-check-macros">Type check macros</a></li>
<li><a class="reference internal" href="#direct-api-functions">Direct API functions</a></li>
<li><a class="reference internal" href="#macros">Macros</a></li>
</ul>
</li>
</ul>
<h4>Previous topic</h4>
<p class="topless"><a href="bytes.html"
title="previous chapter">Bytes Objects</a></p>
<h4>Next topic</h4>
<p class="topless"><a href="unicode.html"
title="next chapter">Unicode Objects and Codecs</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/bytearray.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="unicode.html" title="Unicode Objects and Codecs"
>next</a> |</li>
<li class="right" >
<a href="bytes.html" title="Bytes Objects"
>previous</a> |</li>
<li><img src="../_static/py.svg" alt="python logo" style="vertical-align: middle; margin-top: -1px"/></li>
<li><a href="https://www.python.org/">Python</a> »</li>
<li class="switchers">
<div class="language_switcher_placeholder"></div>
<div class="version_switcher_placeholder"></div>
</li>
<li>
</li>
<li id="cpython-language-and-version">
<a href="../index.html">3.10.12 Documentation</a> »
</li>
<li class="nav-item nav-item-1"><a href="index.html" >Python/C API Reference Manual</a> »</li>
<li class="nav-item nav-item-2"><a href="concrete.html" >Concrete Objects Layer</a> »</li>
<li class="nav-item nav-item-this"><a href="">Byte Array Objects</a></li>
<li class="right">
<div class="inline-search" role="search">
<form class="inline-search" action="../search.html" method="get">
<input placeholder="Quick search" aria-label="Quick search" type="text" name="q" />
<input type="submit" value="Go" />
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
|
</li>
</ul>
</div>
<div class="footer">
© <a href="../copyright.html">Copyright</a> 2001-2025, Python Software Foundation.
<br />
This page is licensed under the Python Software Foundation License Version 2.
<br />
Examples, recipes, and other code in the documentation are additionally licensed under the Zero Clause BSD License.
<br />
See <a href="/license.html">History and License</a> for more information.<br />
<br />
The Python Software Foundation is a non-profit corporation.
<a href="https://www.python.org/psf/donations/">Please donate.</a>
<br />
<br />
Last updated on August 15, 2025.
<a href="/bugs.html">Found a bug</a>?
<br />
Created using <a href="https://www.sphinx-doc.org/">Sphinx</a> 4.3.2.
</div>
</body>
</html>