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<a name="Python-Commands"></a>
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<hr>
<a name="Python-Commands-1"></a>
<h4 class="subsection">23.2.1 Python Commands</h4>
<a name="index-python-commands"></a>
<a name="index-commands-to-access-python"></a>

<p><small>GDB</small> provides two commands for accessing the Python interpreter,
and one related setting:
</p>
<dl compact="compact">
<dd><a name="index-python_002dinteractive"></a>
<a name="index-pi"></a>
</dd>
<dt><code>python-interactive <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt>
<dt><code>pi <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt>
<dd><p>Without an argument, the <code>python-interactive</code> command can be used
to start an interactive Python prompt.  To return to <small>GDB</small>,
type the <code>EOF</code> character (e.g., <kbd>Ctrl-D</kbd> on an empty prompt).
</p>
<p>Alternatively, a single-line Python command can be given as an
argument and evaluated.  If the command is an expression, the result
will be printed; otherwise, nothing will be printed.  For example:
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) python-interactive 2 + 3
5
</pre></div>

<a name="index-python-1"></a>
<a name="index-py"></a>
</dd>
<dt><code>python <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt>
<dt><code>py <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt>
<dd><p>The <code>python</code> command can be used to evaluate Python code.
</p>
<p>If given an argument, the <code>python</code> command will evaluate the
argument as a Python command.  For example:
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) python print 23
23
</pre></div>

<p>If you do not provide an argument to <code>python</code>, it will act as a
multi-line command, like <code>define</code>.  In this case, the Python
script is made up of subsequent command lines, given after the
<code>python</code> command.  This command list is terminated using a line
containing <code>end</code>.  For example:
</p>
<div class="smallexample">
<pre class="smallexample">(gdb) python
&gt;print 23
&gt;end
23
</pre></div>

<a name="index-set-python-print_002dstack"></a>
</dd>
<dt><code>set python print-stack</code></dt>
<dd><p>By default, <small>GDB</small> will print only the message component of a
Python exception when an error occurs in a Python script.  This can be
controlled using <code>set python print-stack</code>: if <code>full</code>, then
full Python stack printing is enabled; if <code>none</code>, then Python stack
and message printing is disabled; if <code>message</code>, the default, only
the message component of the error is printed.
</p></dd>
</dl>

<p>It is also possible to execute a Python script from the <small>GDB</small>
interpreter:
</p>
<dl compact="compact">
<dt><code>source <samp>script-name</samp></code></dt>
<dd><p>The script name must end with &lsquo;<samp>.py</samp>&rsquo; and <small>GDB</small> must be configured
to recognize the script language based on filename extension using
the <code>script-extension</code> setting.  See <a href="Extending-GDB.html#Extending-GDB">Extending GDB</a>.
</p></dd>
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