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Next: <a href="Redirecting-the-output-of-spawned-processes.html#Redirecting-the-output-of-spawned-processes" accesskey="n" rel="next">Redirecting the output of spawned processes</a>, Previous: <a href="Hello-World_0021-in-python.html#Hello-World_0021-in-python" accesskey="p" rel="previous">Hello World! in python</a>, Up: <a href="Python-FAQ.html#Python-FAQ" accesskey="u" rel="up">Python FAQ</a> &nbsp; [<a href="Index-table.html#Index-table" title="Index" rel="index">Index</a>]</p>
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<h4 class="subsubsection">16.8.7.2 Spawning external processes</h4>

<p>There exist various solutions to spawn external processes from a script:
</p>
<ul>
<li> Use the functionalities provided by the <code>GPS.Process</code> class
</li><li> Execute a GPS action through <code>GPS.execute_action</code>.

<p>This action should have an <code>&lt;external&gt;</code> XML node indicating how to
launch the process
</p>
</li><li> Create a pipe and execute the process with <code>os.popen()</code> calls

<p>This solution doesn&rsquo;t provide a full interaction with the process, though.
</p>
</li><li> Use a standard expect library of Python

<p>The use of an expect library may be a good solution. There are various python
expect libraries that already exist.
</p>
<p>These libraries generally try to copy the parameters of the standard <code>file</code>
class. They may fail doing so, as GPS&rsquo;s consoles do not fully emulate all
the primitive functions of that class (there is no file descriptor for
instance).
</p>
<p>When possible, it is recommended to use one of the methods above instead.
</p></li></ul>




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gnat-gps-doc 5.0-16 / usr / share / doc / gnat-gps / html / Spawning-external-processes.html
