1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2021 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with the 8Invariant Sections being "Free Software" and "Free Software Needs 9Free Documentation", with the Front-Cover Texts being "A GNU Manual," 10and with the Back-Cover Texts as in (a) below. 11 12(a) The FSF's Back-Cover Text is: "You are free to copy and modify 13this GNU Manual. 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To return to <small>GDB</small>, 86type the <code>EOF</code> character (e.g., <kbd>Ctrl-D</kbd> on an empty prompt). 87</p> 88<p>Alternatively, a single-line Python command can be given as an 89argument and evaluated. If the command is an expression, the result 90will be printed; otherwise, nothing will be printed. For example: 91</p> 92<div class="smallexample"> 93<pre class="smallexample">(gdb) python-interactive 2 + 3 945 95</pre></div> 96 97<a name="index-python-1"></a> 98<a name="index-py"></a> 99</dd> 100<dt><code>python <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt> 101<dt><code>py <span class="roman">[</span><var>command</var><span class="roman">]</span></code></dt> 102<dd><p>The <code>python</code> command can be used to evaluate Python code. 103</p> 104<p>If given an argument, the <code>python</code> command will evaluate the 105argument as a Python command. For example: 106</p> 107<div class="smallexample"> 108<pre class="smallexample">(gdb) python print 23 10923 110</pre></div> 111 112<p>If you do not provide an argument to <code>python</code>, it will act as a 113multi-line command, like <code>define</code>. In this case, the Python 114script is made up of subsequent command lines, given after the 115<code>python</code> command. This command list is terminated using a line 116containing <code>end</code>. For example: 117</p> 118<div class="smallexample"> 119<pre class="smallexample">(gdb) python 120>print 23 121>end 12223 123</pre></div> 124 125<a name="index-set-python-print_002dstack"></a> 126</dd> 127<dt><code>set python print-stack</code></dt> 128<dd><p>By default, <small>GDB</small> will print only the message component of a 129Python exception when an error occurs in a Python script. This can be 130controlled using <code>set python print-stack</code>: if <code>full</code>, then 131full Python stack printing is enabled; if <code>none</code>, then Python stack 132and message printing is disabled; if <code>message</code>, the default, only 133the message component of the error is printed. 134</p></dd> 135</dl> 136 137<p>It is also possible to execute a Python script from the <small>GDB</small> 138interpreter: 139</p> 140<dl compact="compact"> 141<dt><code>source <samp>script-name</samp></code></dt> 142<dd><p>The script name must end with ‘<samp>.py</samp>’ and <small>GDB</small> must be configured 143to recognize the script language based on filename extension using 144the <code>script-extension</code> setting. See <a href="Extending-GDB.html#Extending-GDB">Extending GDB</a>. 145</p></dd> 146</dl> 147 148<hr> 149<div class="header"> 150<p> 151Next: <a href="Python-API.html#Python-API" accesskey="n" rel="next">Python API</a>, Up: <a href="Python.html#Python" accesskey="u" rel="up">Python</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> 152</div> 153 154 155 156</body> 157</html> 158