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17<title>Debugging with GDB: Logging Output</title>
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64<a name="Logging-Output"></a>
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67Previous: <a href="Shell-Commands.html#Shell-Commands" accesskey="p" rel="previous">Shell Commands</a>, Up: <a href="Invocation.html#Invocation" accesskey="u" rel="up">Invocation</a> &nbsp; [<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>
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70<a name="Logging-Output-1"></a>
71<h3 class="section">2.4 Logging Output</h3>
72<a name="index-logging-GDB-output"></a>
73<a name="index-save-GDB-output-to-a-file"></a>
74
75<p>You may want to save the output of <small>GDB</small> commands to a file.
76There are several commands to control <small>GDB</small>&rsquo;s logging.
77</p>
78<dl compact="compact">
79<dd><a name="index-set-logging"></a>
80</dd>
81<dt><code>set logging on</code></dt>
82<dd><p>Enable logging.
83</p></dd>
84<dt><code>set logging off</code></dt>
85<dd><p>Disable logging.
86<a name="index-logging-file-name"></a>
87</p></dd>
88<dt><code>set logging file <var>file</var></code></dt>
89<dd><p>Change the name of the current logfile.  The default logfile is <samp>gdb.txt</samp>.
90</p></dd>
91<dt><code>set logging overwrite [on|off]</code></dt>
92<dd><p>By default, <small>GDB</small> will append to the logfile.  Set <code>overwrite</code> if
93you want <code>set logging on</code> to overwrite the logfile instead.
94</p></dd>
95<dt><code>set logging redirect [on|off]</code></dt>
96<dd><p>By default, <small>GDB</small> output will go to both the terminal and the logfile.
97Set <code>redirect</code> if you want output to go only to the log file.
98</p></dd>
99<dt><code>set logging debugredirect [on|off]</code></dt>
100<dd><p>By default, <small>GDB</small> debug output will go to both the terminal and the logfile.
101Set <code>debugredirect</code> if you want debug output to go only to the log file.
102<a name="index-show-logging"></a>
103</p></dd>
104<dt><code>show logging</code></dt>
105<dd><p>Show the current values of the logging settings.
106</p></dd>
107</dl>
108
109<p>You can also redirect the output of a <small>GDB</small> command to a
110shell command.  See <a href="Shell-Commands.html#pipe">pipe</a>.
111</p>
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