LinuxQuestions.org - where does exim4 keep variable values?

Good day,

I've installed exim4 via apt, answered a couple of questions during initial configuration, and now I'm trying to understand config files.
When trying to exim -bP | grep local_interfaces, I get local_interfaces = 192.168.0.10, which, I assume, comes from these lines in exim4.conf:

Code:

.ifdef MAIN_LOCAL_INTERFACES

local_interfaces = MAIN_LOCAL_INTERFACES

.endif

However I fail to understand where the IP comes from; indeed local interfaces parameter was configured during the interactive setup, but where is this variable defined/stored? As far as I understand if exim was compiled manually it'd be hardcoded, but that's not the case with installing it via apt, right?

Of course any parameter can be overridden, but I'm curious where the value of MAIN_LOCAL_INTERFACES (and other variables) is stored.

Thanks.