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<title>GDB&rsquo;s Obsolete Annotations: Annotations Overview</title>

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<a name="Annotations-Overview"></a>
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<p>
Next: <a href="Limitations.html#Limitations" accesskey="n" rel="next">Limitations</a>, Previous: <a href="index.html#Top" accesskey="p" rel="prev">Top</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>]</p>
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<a name="What-is-an-Annotation_003f"></a>
<h2 class="chapter">1 What is an Annotation?</h2>
<a name="index-annotations"></a>

<p>To produce obsolete level two annotations, start <small>GDB</small> with the
<code>--annotate=2</code> option.
</p>
<p>Annotations start with a newline character, two &lsquo;<samp>control-z</samp>&rsquo;
characters, and the name of the annotation.  If there is no additional
information associated with this annotation, the name of the annotation
is followed immediately by a newline.  If there is additional
information, the name of the annotation is followed by a space, the
additional information, and a newline.  The additional information
cannot contain newline characters.
</p>
<p>Any output not beginning with a newline and two &lsquo;<samp>control-z</samp>&rsquo;
characters denotes literal output from <small>GDB</small>.  Currently there is
no need for <small>GDB</small> to output a newline followed by two
&lsquo;<samp>control-z</samp>&rsquo; characters, but if there was such a need, the
annotations could be extended with an &lsquo;<samp>escape</samp>&rsquo; annotation which
means those three characters as output.
</p>
<p>A simple example of starting up <small>GDB</small> with annotations is:
</p>
<div class="smallexample">
<pre class="smallexample">$ gdb --annotate=2
GNU GDB 5.0
Copyright 2000 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License,
and you are welcome to change it and/or distribute copies of it
under certain conditions.
Type &quot;show copying&quot; to see the conditions.
There is absolutely no warranty for GDB.  Type &quot;show warranty&quot;
for details.
This GDB was configured as &quot;sparc-sun-sunos4.1.3&quot;

^Z^Zpre-prompt
(gdb) 
^Z^Zprompt
quit

^Z^Zpost-prompt
$ 
</pre></div>

<p>Here &lsquo;<samp>quit</samp>&rsquo; is input to <small>GDB</small>; the rest is output from
<small>GDB</small>.  The three lines beginning &lsquo;<samp>^Z^Z</samp>&rsquo; (where &lsquo;<samp>^Z</samp>&rsquo;
denotes a &lsquo;<samp>control-z</samp>&rsquo; character) are annotations; the rest is
output from <small>GDB</small>.
</p>


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