I am not 100% sure if its a bug or feature request. And, I have already asked this question in mailing list.

### Description

I was trying to pass environment variables to Kamailio that are definitely there in the container. Also, I am trying to use the environment variables to specify ports for Kamailio to listen on. I have already tried passing variables through -A option but to no avail.

### Expected behavior Please note that these values are known at start time so should work.

#### Actual observed behavior Errors

#### Debugging Data I have tried:

``` #!define TLS_TO_LISTEN tls:TLS_IP:$env(TLS_PORT) ```

I have also tried using in EVAPI `bind_addr` modparam but that throws errors: ``` #!define EVAPI_LISTEN "0.0.0.0:EVAPI_PORT" .. modparam("evapi", "bind_addr", EVAPI_LISTEN ) // IP and port to listen on for incoming TCP connections. ``` Error: ``` ERROR: evapi [evapi_mod.c:156]: mod_init(): invalid port: 0 ```

### Additional Information

``` version: kamailio 5.4.2 (x86_64/linux) f8885c ```

* **Operating System**: Docker Container: ``` Linux fe1933ee6208 4.15.0-124-generic #127-Ubuntu SMP Fri Nov 6 10:54:43 UTC 2020 x86_64 GNU/Linux ```