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<title>Debugging with GDB: Startup</title>

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<a name="Startup"></a>
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<p>
Previous: <a href="Mode-Options.html#Mode-Options" accesskey="p" rel="previous">Mode Options</a>, Up: <a href="Invoking-GDB.html#Invoking-GDB" accesskey="u" rel="up">Invoking GDB</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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<hr>
<a name="What-GDB-Does-During-Startup"></a>
<h4 class="subsection">2.1.3 What <small>GDB</small> Does During Startup</h4>
<a name="index-GDB-startup"></a>

<p>Here&rsquo;s the description of what <small>GDB</small> does during session startup:
</p>
<ol>
<li> Sets up the command interpreter as specified by the command line
(see <a href="Mode-Options.html#Mode-Options">interpreter</a>).

</li><li> <a name="index-init-file"></a>
Reads the system-wide <em>init file</em> (if <samp>--with-system-gdbinit</samp> was
used when building <small>GDB</small>; see <a href="System_002dwide-configuration.html#System_002dwide-configuration">System-wide configuration and settings</a>) and the files in the system-wide
gdbinit directory (if <samp>--with-system-gdbinit-dir</samp> was used) and executes
all the commands in those files.  The files need to be named with a <samp>.gdb</samp>
extension to be interpreted as <small>GDB</small> commands, or they can be written
in a supported scripting language with an appropriate file extension.

<a name="Home-Directory-Init-File"></a></li><li> Reads the init file (if any) in your home directory<a name="DOCF1" href="#FOOT1"><sup>1</sup></a> and executes all the commands in
that file.

<a name="Option-_002dinit_002deval_002dcommand"></a></li><li> Executes commands and command files specified by the &lsquo;<samp>-iex</samp>&rsquo; and
&lsquo;<samp>-ix</samp>&rsquo; options in their specified order.  Usually you should use the
&lsquo;<samp>-ex</samp>&rsquo; and &lsquo;<samp>-x</samp>&rsquo; options instead, but this way you can apply
settings before <small>GDB</small> init files get executed and before inferior
gets loaded.

</li><li> Processes command line options and operands.

<a name="Init-File-in-the-Current-Directory-during-Startup"></a></li><li> Reads and executes the commands from init file (if any) in the current
working directory as long as &lsquo;<samp>set auto-load local-gdbinit</samp>&rsquo; is set to
&lsquo;<samp>on</samp>&rsquo; (see <a href="Init-File-in-the-Current-Directory.html#Init-File-in-the-Current-Directory">Init File in the Current Directory</a>).
This is only done if the current directory is
different from your home directory.  Thus, you can have more than one
init file, one generic in your home directory, and another, specific
to the program you are debugging, in the directory where you invoke
<small>GDB</small>.

</li><li> If the command line specified a program to debug, or a process to
attach to, or a core file, <small>GDB</small> loads any auto-loaded
scripts provided for the program or for its loaded shared libraries.
See <a href="Auto_002dloading.html#Auto_002dloading">Auto-loading</a>.

<p>If you wish to disable the auto-loading during startup,
you must do something like the following:
</p>
<div class="smallexample">
<pre class="smallexample">$ gdb -iex &quot;set auto-load python-scripts off&quot; myprogram
</pre></div>

<p>Option &lsquo;<samp>-ex</samp>&rsquo; does not work because the auto-loading is then turned
off too late.
</p>
</li><li> Executes commands and command files specified by the &lsquo;<samp>-ex</samp>&rsquo; and
&lsquo;<samp>-x</samp>&rsquo; options in their specified order.  See <a href="Command-Files.html#Command-Files">Command Files</a>, for
more details about <small>GDB</small> command files.

</li><li> Reads the command history recorded in the <em>history file</em>.
See <a href="Command-History.html#Command-History">Command History</a>, for more details about the command history and the
files where <small>GDB</small> records it.
</li></ol>

<p>Init files use the same syntax as <em>command files</em> (see <a href="Command-Files.html#Command-Files">Command Files</a>) and are processed by <small>GDB</small> in the same way.  The init
file in your home directory can set options (such as &lsquo;<samp>set
complaints</samp>&rsquo;) that affect subsequent processing of command line options
and operands.  Init files are not executed if you use the &lsquo;<samp>-nx</samp>&rsquo;
option (see <a href="Mode-Options.html#Mode-Options">Choosing Modes</a>).
</p>
<p>To display the list of init files loaded by gdb at startup, you
can use <kbd>gdb --help</kbd>.
</p>
<a name="index-init-file-name"></a>
<a name="index-_002egdbinit"></a>
<a name="index-gdb_002eini"></a>
<p>The <small>GDB</small> init files are normally called <samp>.gdbinit</samp>.
The DJGPP port of <small>GDB</small> uses the name <samp>gdb.ini</samp>, due to
the limitations of file names imposed by DOS filesystems.  The Windows
port of <small>GDB</small> uses the standard name, but if it finds a
<samp>gdb.ini</samp> file in your home directory, it warns you about that
and suggests to rename the file to the standard name.
</p>

<div class="footnote">
<hr>
<h4 class="footnotes-heading">Footnotes</h4>

<h3><a name="FOOT1" href="#DOCF1">(1)</a></h3>
<p>On
DOS/Windows systems, the home directory is the one pointed to by the
<code>HOME</code> environment variable.</p>
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Previous: <a href="Mode-Options.html#Mode-Options" accesskey="p" rel="previous">Mode Options</a>, Up: <a href="Invoking-GDB.html#Invoking-GDB" accesskey="u" rel="up">Invoking GDB</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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