- configuration variables can be declared in the script:

- configuration variables can be declared in the script:
<group_name>.<var_name> = <value> [descr <description>]
- free the list of cfg groups during exit

It is possible to declare new config variables in the script,
and retrieve them via select calls. The variables behave the same
way as the core or module variables, they are constant during
message processing, and they can be modified by the cfg drivers,
for example via RPC calls.

gateway.destination = "127.0.0.1" descr "IP addr of the gateway"
gateway.enabled = 1 descr "enable/disable the gateway"

route[0] {
	...
	if (@cfg_get.gateway.enabled == 1) {
		xlset_destination("<sip:%@cfg_get.gateway.destination>");
	}
	...
}