Hello,

I’m trying to change contact header in SIP response message by stripping first characters (for testing only) as below :

$ct = $(ct{s.strip,25});

But I got below error saying that $ct is read-only:

0(15410) : <core> [cfg.y:3419]: yyerror_at(): parse error in config file /usr/local/etc/kamailio/kamailio.cfg, line 575, column 5-7: read only pvar in assignment left side

ERROR: bad config file (1 errors)

The question is how can I change contact header before it’s sending of Kamailio?

Thanks

Ali