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<title>Debugging with GDB: File Caching</title>

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<a name="File-Caching"></a>
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<hr>
<a name="File-Caching-1"></a>
<h3 class="section">18.2 File Caching</h3>
<a name="index-caching-of-opened-files"></a>
<a name="index-caching-of-bfd-objects"></a>

<p>To speed up file loading, and reduce memory usage, <small>GDB</small> will
reuse the <code>bfd</code> objects used to track open files.  See <a href="http://sourceware.org/binutils/docs/bfd/index.html#Top">BFD</a> in <cite>The Binary File Descriptor Library</cite>.  The following commands
allow visibility and control of the caching behavior.
</p>
<dl compact="compact">
<dd><a name="index-maint-info-bfds"></a>
</dd>
<dt><code>maint info bfds</code></dt>
<dd><p>This prints information about each <code>bfd</code> object that is known to
<small>GDB</small>.
</p>
<a name="index-maint-set-bfd_002dsharing"></a>
<a name="index-maint-show-bfd_002dsharing"></a>
<a name="index-bfd-caching"></a>
</dd>
<dt><code>maint set bfd-sharing</code></dt>
<dt><code>maint show bfd-sharing</code></dt>
<dd><p>Control whether <code>bfd</code> objects can be shared.  When sharing is
enabled <small>GDB</small> reuses already open <code>bfd</code> objects rather
than reopening the same file.  Turning sharing off does not cause
already shared <code>bfd</code> objects to be unshared, but all future files
that are opened will create a new <code>bfd</code> object.  Similarly,
re-enabling sharing does not cause multiple existing <code>bfd</code>
objects to be collapsed into a single shared <code>bfd</code> object.
</p>
<a name="index-set-debug-bfd_002dcache-level"></a>
<a name="index-bfd-caching-1"></a>
</dd>
<dt><code>set debug bfd-cache <var>level</var></code></dt>
<dd><p>Turns on debugging of the bfd cache, setting the level to <var>level</var>.
</p>
<a name="index-show-debug-bfd_002dcache"></a>
<a name="index-bfd-caching-2"></a>
</dd>
<dt><code>show debug bfd-cache</code></dt>
<dd><p>Show the current debugging level of the bfd cache.
</p></dd>
</dl>


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