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<a name="Target-Commands"></a>
<div class="header">
<p>
Next: <a href="Byte-Order.html#Byte-Order" accesskey="n" rel="next">Byte Order</a>, Previous: <a href="Active-Targets.html#Active-Targets" accesskey="p" rel="previous">Active Targets</a>, Up: <a href="Targets.html#Targets" accesskey="u" rel="up">Targets</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>
</div>
<hr>
<a name="Commands-for-Managing-Targets"></a>
<h3 class="section">19.2 Commands for Managing Targets</h3>

<dl compact="compact">
<dt><code>target <var>type</var> <var>parameters</var></code></dt>
<dd><p>Connects the <small>GDB</small> host environment to a target machine or
process.  A target is typically a protocol for talking to debugging
facilities.  You use the argument <var>type</var> to specify the type or
protocol of the target machine.
</p>
<p>Further <var>parameters</var> are interpreted by the target protocol, but
typically include things like device names or host names to connect
with, process numbers, and baud rates.
</p>
<p>The <code>target</code> command does not repeat if you press <tt class="key">RET</tt> again
after executing the command.
</p>
<a name="index-help-target"></a>
</dd>
<dt><code>help target</code></dt>
<dd><p>Displays the names of all targets available.  To display targets
currently selected, use either <code>info target</code> or <code>info files</code>
(see <a href="Files.html#Files">Commands to Specify Files</a>).
</p>
</dd>
<dt><code>help target <var>name</var></code></dt>
<dd><p>Describe a particular target, including any parameters necessary to
select it.
</p>
<a name="index-set-gnutarget"></a>
</dd>
<dt><code>set gnutarget <var>args</var></code></dt>
<dd><p><small>GDB</small> uses its own library BFD to read your files.  <small>GDB</small>
knows whether it is reading an <em>executable</em>,
a <em>core</em>, or a <em>.o</em> file; however, you can specify the file format
with the <code>set gnutarget</code> command.  Unlike most <code>target</code> commands,
with <code>gnutarget</code> the <code>target</code> refers to a program, not a machine.
</p>
<blockquote>
<p><em>Warning:</em> To specify a file format with <code>set gnutarget</code>,
you must know the actual BFD name.
</p></blockquote>

<p>See <a href="Files.html#Files">Commands to Specify Files</a>.
</p>
<a name="index-show-gnutarget"></a>
</dd>
<dt><code>show gnutarget</code></dt>
<dd><p>Use the <code>show gnutarget</code> command to display what file format
<code>gnutarget</code> is set to read.  If you have not set <code>gnutarget</code>,
<small>GDB</small> will determine the file format for each file automatically,
and <code>show gnutarget</code> displays &lsquo;<samp>The current BFD target is &quot;auto&quot;</samp>&rsquo;.
</p></dd>
</dl>

<a name="index-common-targets"></a>
<p>Here are some common targets (available, or not, depending on the GDB
configuration):
</p>
<dl compact="compact">
<dd><a name="index-target"></a>
</dd>
<dt><code>target exec <var>program</var></code></dt>
<dd><a name="index-executable-file-target"></a>
<p>An executable file.  &lsquo;<samp>target exec <var>program</var></samp>&rsquo; is the same as
&lsquo;<samp>exec-file <var>program</var></samp>&rsquo;.
</p>
</dd>
<dt><code>target core <var>filename</var></code></dt>
<dd><a name="index-core-dump-file-target"></a>
<p>A core dump file.  &lsquo;<samp>target core <var>filename</var></samp>&rsquo; is the same as
&lsquo;<samp>core-file <var>filename</var></samp>&rsquo;.
</p>
</dd>
<dt><code>target remote <var>medium</var></code></dt>
<dd><a name="index-remote-target"></a>
<p>A remote system connected to <small>GDB</small> via a serial line or network
connection.  This command tells <small>GDB</small> to use its own remote
protocol over <var>medium</var> for debugging.  See <a href="Remote-Debugging.html#Remote-Debugging">Remote Debugging</a>.
</p>
<p>For example, if you have a board connected to <samp>/dev/ttya</samp> on the
machine running <small>GDB</small>, you could say:
</p>
<div class="smallexample">
<pre class="smallexample">target remote /dev/ttya
</pre></div>

<p><code>target remote</code> supports the <code>load</code> command.  This is only
useful if you have some other way of getting the stub to the target
system, and you can put it somewhere in memory where it won&rsquo;t get
clobbered by the download.
</p>
</dd>
<dt><code>target sim <span class="roman">[</span><var>simargs</var><span class="roman">]</span> &hellip;</code></dt>
<dd><a name="index-built_002din-simulator-target"></a>
<p>Builtin CPU simulator.  <small>GDB</small> includes simulators for most architectures.
In general,
</p><div class="smallexample">
<pre class="smallexample">        target sim
        load
        run
</pre></div>
<p>works; however, you cannot assume that a specific memory map, device
drivers, or even basic I/O is available, although some simulators do
provide these.  For info about any processor-specific simulator details,
see the appropriate section in <a href="Embedded-Processors.html#Embedded-Processors">Embedded
Processors</a>.
</p>
</dd>
<dt><code>target native</code></dt>
<dd><a name="index-native-target"></a>
<p>Setup for local/native process debugging.  Useful to make the
<code>run</code> command spawn native processes (likewise <code>attach</code>,
etc.) even when <code>set auto-connect-native-target</code> is <code>off</code>
(see <a href="Starting.html#set-auto_002dconnect_002dnative_002dtarget">set auto-connect-native-target</a>).
</p>
</dd>
</dl>

<p>Different targets are available on different configurations of <small>GDB</small>;
your configuration may have more or fewer targets.
</p>
<p>Many remote targets require you to download the executable&rsquo;s code once
you&rsquo;ve successfully established a connection.  You may wish to control
various aspects of this process.
</p>
<dl compact="compact">
<dt><code>set hash</code></dt>
<dd><a name="index-set-hash_002c-for-remote-monitors"></a>
<a name="index-hash-mark-while-downloading"></a>
<p>This command controls whether a hash mark &lsquo;<samp>#</samp>&rsquo; is displayed while
downloading a file to the remote monitor.  If on, a hash mark is
displayed after each S-record is successfully downloaded to the
monitor.
</p>
</dd>
<dt><code>show hash</code></dt>
<dd><a name="index-show-hash_002c-for-remote-monitors"></a>
<p>Show the current status of displaying the hash mark.
</p>
</dd>
<dt><code>set debug monitor</code></dt>
<dd><a name="index-set-debug-monitor"></a>
<a name="index-display-remote-monitor-communications"></a>
<p>Enable or disable display of communications messages between
<small>GDB</small> and the remote monitor.
</p>
</dd>
<dt><code>show debug monitor</code></dt>
<dd><a name="index-show-debug-monitor"></a>
<p>Show the current status of displaying communications between
<small>GDB</small> and the remote monitor.
</p></dd>
</dl>

<dl compact="compact">
<dd>
<a name="index-load-filename-offset"></a>
</dd>
<dt><code>load <var>filename</var> <var>offset</var></code></dt>
<dd><a name="load"></a><p>Depending on what remote debugging facilities are configured into
<small>GDB</small>, the <code>load</code> command may be available.  Where it exists, it
is meant to make <var>filename</var> (an executable) available for debugging
on the remote system&mdash;by downloading, or dynamic linking, for example.
<code>load</code> also records the <var>filename</var> symbol table in <small>GDB</small>, like
the <code>add-symbol-file</code> command.
</p>
<p>If your <small>GDB</small> does not have a <code>load</code> command, attempting to
execute it gets the error message &ldquo;<code>You can't do that when your
target is &hellip;</code>&rdquo;
</p>
<p>The file is loaded at whatever address is specified in the executable.
For some object file formats, you can specify the load address when you
link the program; for other formats, like a.out, the object file format
specifies a fixed address.
</p>
<p>It is also possible to tell <small>GDB</small> to load the executable file at a
specific offset described by the optional argument <var>offset</var>.  When
<var>offset</var> is provided, <var>filename</var> must also be provided.
</p>
<p>Depending on the remote side capabilities, <small>GDB</small> may be able to
load programs into flash memory.
</p>
<p><code>load</code> does not repeat if you press <tt class="key">RET</tt> again after using it.
</p></dd>
</dl>

<dl compact="compact">
<dd>
<a name="index-flash_002derase"></a>
</dd>
<dt><code>flash-erase</code></dt>
<dd><a name="flash_002derase"></a>
<p>Erases all known flash memory regions on the target.
</p>
</dd>
</dl>

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