1<html lang="en"> 2<head> 3<title>Python Commands - Debugging with GDB</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Debugging with GDB"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Python.html#Python" title="Python"> 9<link rel="next" href="Python-API.html#Python-API" title="Python API"> 10<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 11<!-- 12Copyright (C) 1988-2013 Free Software Foundation, Inc. 13 14Permission is granted to copy, distribute and/or modify this document 15under the terms of the GNU Free Documentation License, Version 1.3 or 16any later version published by the Free Software Foundation; with the 17Invariant Sections being ``Free Software'' and ``Free Software Needs 18Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,'' 19and with the Back-Cover Texts as in (a) below. 20 21(a) The FSF's Back-Cover Text is: ``You are free to copy and modify 22this GNU Manual. 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To return to <span class="sc">gdb</span>, 59type the <code>EOF</code> character (e.g., <kbd>Ctrl-D</kbd> on an empty prompt). 60 61 <p>Alternatively, a single-line Python command can be given as an 62argument and evaluated. If the command is an expression, the result 63will be printed; otherwise, nothing will be printed. For example: 64 65 <pre class="smallexample"> (gdb) python-interactive 2 + 3 66 5 67</pre> 68 <p><a name="index-python-1724"></a><a name="index-py-1725"></a><br><dt><code>python </code><span class="roman">[</span><var>command</var><span class="roman">]</span><dt><code>py </code><span class="roman">[</span><var>command</var><span class="roman">]</span><dd>The <code>python</code> command can be used to evaluate Python code. 69 70 <p>If given an argument, the <code>python</code> command will evaluate the 71argument as a Python command. For example: 72 73 <pre class="smallexample"> (gdb) python print 23 74 23 75</pre> 76 <p>If you do not provide an argument to <code>python</code>, it will act as a 77multi-line command, like <code>define</code>. In this case, the Python 78script is made up of subsequent command lines, given after the 79<code>python</code> command. This command list is terminated using a line 80containing <code>end</code>. For example: 81 82 <pre class="smallexample"> (gdb) python 83 Type python script 84 End with a line saying just "end". 85 >print 23 86 >end 87 23 88</pre> 89 <p><a name="index-set-python-print_002dstack-1726"></a><br><dt><code>set python print-stack</code><dd>By default, <span class="sc">gdb</span> will print only the message component of a 90Python exception when an error occurs in a Python script. This can be 91controlled using <code>set python print-stack</code>: if <code>full</code>, then 92full Python stack printing is enabled; if <code>none</code>, then Python stack 93and message printing is disabled; if <code>message</code>, the default, only 94the message component of the error is printed. 95</dl> 96 97 <p>It is also possible to execute a Python script from the <span class="sc">gdb</span> 98interpreter: 99 100 <dl> 101<dt><code>source </code><samp><span class="file">script-name</span></samp><dd>The script name must end with ‘<samp><span class="samp">.py</span></samp>’ and <span class="sc">gdb</span> must be configured 102to recognize the script language based on filename extension using 103the <code>script-extension</code> setting. See <a href="Extending-GDB.html#Extending-GDB">Extending GDB</a>. 104 105 <br><dt><code>python execfile ("script-name")</code><dd>This method is based on the <code>execfile</code> Python built-in function, 106and thus is always available. 107</dl> 108 109 </body></html> 110 111