Hello

this is what I normally use:

if (defined $var(x)) {...}

Regards

Javi

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Message: 4 Date: Tue, 6 Mar 2012 20:05:32 -0600 From: Krishna Kurapati kkurapat@gmail.com Subject: [SR-Users] Improving Kamailo configuration parser ... To: kamailio users sr-users@lists.sip-router.org Message-ID: <CAOzCjAfcaRQ+HT3r+mwckPyaVJH+EVFWNa_Hj6tAhGyD2DaMJA@mail.gmail.com

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I used

if ($var(x) != null) { ... }

in one of the routes, and tried to run Kamailio server. The server exited with an error. I did not know why.

Once I changed it to if ($var(x) != $null) {} the error went away. I missed $ infront null. I think it is hard to trace such problems once a large chunk of logic is written since many of us come from C++ and scripting background where $null is not a common practice.

Also if I tried to use if (!$var(x)) { ... } Kamailio tries to convert the value of $var(x) to integer. prints WARNINGS in the log when the $var(x) consists of a string.

Krish Kura