2013/3/20 anatoly techtonik <span dir="ltr">&lt;<a href="mailto:techtonik@gmail.com" target="_blank">techtonik@gmail.com</a>&gt;</span><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">Hi,<div><br></div><div>I&#39;ve created a module to dump function trace during execution of Python script. You can see session example in attachment. The format is of PHP Xdebug tool [2] just because I had some scripts from the past to analyze it.</div>



<div><br></div><div><div>The module uses sys.settrace() to analyse frames in &#39;call&#39; events with callback(frame, event, arg).</div><div><br></div><div>Recently I&#39;ve got an anonymous report that some frame misses filename information when run under IDE:</div>



</div><div><a href="https://bitbucket.org/techtonik/xtrace/issue/2/use-of-xtrace-module-within-ide-causes" target="_blank">https://bitbucket.org/techtonik/xtrace/issue/2/use-of-xtrace-module-within-ide-causes</a></div><div>


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There is unlikely to be any more feedback from the user to make me understand and reproduce the behavior, nor there is a sufficient documentation in sys.trace description [1]. So I am on my own. But I can not read C code the CPython is written in, so I ask here.</div>



<div><br></div><div>What are possible execution contexts for Python?</div><div>How each execution context affects data structure that is passed to trace function (frame and arg)?</div></div></blockquote><div><br></div><div>
It&#39;s simpler than that: when running from an interactive session, f_back is empty...</div><div><br></div><div><div>&gt;&gt;&gt; def trace(frame, event, arg):</div><div>...     funcname = frame.f_code.co_name</div><div>
...     if funcname == &#39;&lt;module&gt;&#39;:</div><div>...         print frame.f_back.f_code.co_filename   </div><div>... </div><div>&gt;&gt;&gt; import sys</div><div>&gt;&gt;&gt; sys.settrace(trace)</div><div>&gt;&gt;&gt; 1</div>
<div>Traceback (most recent call last):</div><div>  File &quot;&lt;stdin&gt;&quot;, line 1, in &lt;module&gt;</div><div>  File &quot;&lt;stdin&gt;&quot;, line 4, in trace</div><div>AttributeError: &#39;NoneType&#39; object has no attribute &#39;f_code&#39;</div>
</div><div><br></div></div>-- <br>Amaury Forgeot d&#39;Arc