IMHO,<br><br>I wouldn&#39;t &quot;equalize&quot; non-existent parameter with empty string. There are header parameters (maddr,rport,isfocus) which may not have value and someone (who knows?) might need to check for them. I would just not forbid this option from the config file...
<br><br>I would just use the @ and !@ uses for detecting presence or absence of attributes and letting the == to check for the value once you know it exists. It &quot;complicates&quot; a little bit config file but makes it clearer and I think easier to debug. 
<br><br>So, for me it&#39;s fine changing example config files and documenting it.<br><br>my 0.02,<br>Samuel<br><br><div><span class="gmail_quote">2007/6/8, Michal Matyska &lt;<a href="mailto:michal@iptel.org">michal@iptel.org
</a>&gt;:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Samuel,<br><br>yes it is related to. The resolution of SER-263 was wrong and every test
<br>like&nbsp;&nbsp; if (@select==&quot;&quot;)&nbsp;&nbsp;has returned false, even the return value of<br>the select was empty string.<br><br>But, there is another problem I see in the config (including the example<br>script)...<br><br>There is difference between the (@select) test and (@select!=&quot;&quot;) one.
<br>The latter returns false, if the select framework returns N/A value<br>(e.g. non present header/parameter).<br><br>Intended behaviour was: @X is @route[1].params.lr in this example<br>(as the tag must have value if present rfc3261 
19.3)<br><br>lr parameter&nbsp;&nbsp;&nbsp;&nbsp;test&nbsp;&nbsp;&nbsp;&nbsp;result<br>not present&nbsp;&nbsp;&nbsp;&nbsp; @X&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;false<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;!@X&nbsp;&nbsp;&nbsp;&nbsp; true<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X==&quot;&quot;&nbsp;&nbsp;FALSE*<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X!=&quot;&quot;&nbsp;&nbsp;FALSE*<br><br><br>lr&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;true
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;!@X&nbsp;&nbsp;&nbsp;&nbsp; false<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X==&quot;&quot;&nbsp;&nbsp;true<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X!=&quot;&quot;&nbsp;&nbsp;false<br><br>lr=123&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;true<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;!@X&nbsp;&nbsp;&nbsp;&nbsp; false<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X==&quot;&quot;&nbsp;&nbsp;false
<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;@X!=&quot;&quot;&nbsp;&nbsp;true<br><br><br>As I see the from the example ser.cfg, the tests are done in the<br>(@to.tag==&quot;&quot;) way, which won&#39;t work if the to.tag would return either<br>N/A or the tag value. But it seems it returns the empty string even if
<br>not present, because it was previously working.<br><br>So I ask the community (especially TB potential members) do we want to<br>take care about the select N/A value differently, or shall we make it<br>equal to empty string?
<br><br>Note, that if the answer is yes, it will be very hard to differentiate<br>between parameter not present and parameter without value - well the lr<br>parameter is handled internally, but what others?<br><br>If the anwser is no, keep special N/A value handling, the select must be
<br>reviewed together with the ser.cfg, because (@to.tag==&quot;&quot;) will be false<br>for every tag (because it must have value).<br><br>Michal<br><br>On Čt, 2007-06-07 at 13:56 +0200, samuel wrote:<br>&gt; Michal,<br>
&gt;<br>&gt; I&#39;ve just post a question to users&#39; list about not properly detecting<br>&gt; @to.tag==&quot;&quot;.<br>&gt;<br>&gt; Is this bug related to it??<br>&gt;<br>&gt; Thanks,<br>&gt; Samuel.<br>&gt;<br>&gt; 2007/6/7, Michal Matyska (JIRA) &lt; 
<a href="mailto:tracker@iptel.org">tracker@iptel.org</a>&gt;:<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[ <a href="http://tracker.iptel.org/browse/SER-263?page=all">http://tracker.iptel.org/browse/SER-263?page=all</a> ]<br>&gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Michal Matyska reopened SER-263:
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; --------------------------------<br>&gt;<br>&gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The way it is now resolved is wrong. If the select returns<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; empty string the script test if (@select==&quot;&quot;)&nbsp;&nbsp;is false.
<br>&gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; Using @select=~ &quot;regexp&quot; causes segmentation fault<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; --------------------------------------------------<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Key: SER-263
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; URL: <a href="http://tracker.iptel.org/browse/SER-263">http://tracker.iptel.org/browse/SER-263</a><br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Project: SER<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Issue Type: Bug
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Components: core, Selects<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;Affects Versions: 2.0, Ipteldorf<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Environment: CVS head<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Reporter: Michal Matyska
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Assigned To: Michal Matyska<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Priority: Minor<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Fix For: 2.0, Ipteldorf<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt;<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; If the result of the select is empty string or it is
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; STR_STATIC_INIT ( e.g. @uri.type) the prepatation of left<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; operand (putting \0 behind the string) causes segmentation<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; fault .<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; Program received signal SIGSEGV, Segmentation fault.
<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; comp_str (op=11, left=0xbfad27a4, rtype=5, r=0x81932b0,<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; msg=0x81a1034) at route.c:668<br>&gt;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &gt; 668&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; left-&gt;s[left-&gt;len]=&#39;\0&#39;;<br>&gt;
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