[SR-Users] Retransmission handling

[Daniel-Constantin Mierla]

On 19.10.17 17:41, Alex Balashov wrote:
> On Thu, Oct 19, 2017 at 11:06:21AM +0300, Volkan Oransoy wrote:
>
>> I wonder purpose of this block in default script. What I didn’t understand is the purpose of "t_check_trans()”. Accoording to documentation, this method returns a boolean. So why do we use it even we don’t check output?
>>
>> 	# handle retransmissions
>> 	if (!is_method("ACK")) {
>> 		if(t_precheck_trans()) {
>> 			t_check_trans();
>> 			exit;
>> 		}
>> 		t_check_trans();
>> 	}
> Because t_check_trans() has certain behaviours simply in virtue of being
> called:
>
> https://kamailio.org/docs/modules/5.0.x/modules/tm.html#tm.f.t_check_trans
>
> For example:
>
>    "For ACKs to negative replies or for ACKs to local transactions it will
>     terminate the script if the ACK belongs to a transaction"
>
>
>
Just to highlight, the other section in the docs is also relevant,
respectively stopping the config execution if it was a retransmission
after sending back the last response.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
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