[Serusers] Use of fifo for registration :ul_add: command tutorial

Hi all, I would like to use ser_fifo to register a user; I think the :ul_add: command is the clue, but I don't how to use the fifo to do this. My aim is to do the following: I have a Voip gateway on a customer with a lot of phone number (700) and I would like to authenticate each number. Unfortunately I have to add a small amount of configuration on the voip gateway each time I add a number (uri), moreover I'm not sure this gateway will work with so many numbers, and the bandwidth needed to register each number every 5 minutes will be wasted. The idea is to challenge only one time the gateway and then in ser.cfg if the challenge succeeds I execute a script to register by bulk all the numbers enclosed in a file on the proxy. To do this I have to pass arguments to the fifo using the :ul_add: command, but this is where I'm stuck. I've done this: echo :ul_add:receiving_fifo > /tmp/ser_fifo echo location > /tmp/ser_fifo echo 100 > /tmp/ser_fifo echo <sip:100@10.1.1.1:5060> > /tmp/ser_fifo echo 300 > /tmp/ser_fifo echo 0 > /tmp/ser_fifo echo 2 > /tmp/ser_fifo but it does not work, I think this is due to the receiving_fifo, I have to do something with it to process the response of SER, but what ?? I know I can use the following command to workaround the pbm: Serctl fifo ul_add location ... But it requires one process each time I register a number, and it takes 1 minute on a Celeron 700 for 500 numbers (30 % CPU), and I think using the fifo is a more suitable solution (less CPU consuming). Thanks for your support, Rodrigue PS: I would like to register every 5minutes,cause the customer gateway is able to redirect to PSTN in case of failure.