Hi Antti,

> Oh, didn't know that. That sounds great!
> We were under the impression that the phonesim instances have to be
> running before phonesim plugin loads and the modem .xml configurations
> can't be changed on the fly.

What modem .xml configurations?  I'm lost now.

You have phonesim plugin inside oFono that simply creates modem driver
instances that essentially know two things:
  - IP Address
  - Port number.

When you enable the modem on path /phonesimN, a TCP connection is
established.
When you disable the modem, a TCP connection is killed.

> 
> This new information now removes the need to be able to restart ofono
> just for updating the phonesim modem .xml configurations.
> 

Just restart phonesim on the same port with a new XML file and be done
with it.

> 
>> Or go the route of plugins/stktest.c and tools/stktest.c that we used
>> for unit testing SIM Toolkit.
> 
> The only problem that remains is that there seems to be no way of
> changing the number of modems on the fly as they are read upon phonesim
> plugin initialization from phonesim.conf.

Why is this a problem?

> 
> Now looking at stktest.c I see it opens a socket to communicate with an
> external process.
> 

If by external process you mean oFono... then yes.  The setup is exactly
the same as phonesim, just automated.  Think of stktest as a phonesim
instance with a very limited AT command set, but tells oFono when to
connect ;)

> 
> Would it be acceptable if we implement the following:
> 
> Upon phonesim plugin init we check if a configuration file exists at
>     /etc/ofono/phonesim-control.conf
> 
> The file would contain the following:
> 
>     [control]
>     Port=715517
>     LoadDefaultConfig=0
> 
> Only if the file exists phonesim plugin would then create a _listening_
> socket on the specified port.
> 
> If LoadDefaultConfig is 0 the phonesim plugin would not load
> /etc/ofono/phonesim.conf.
> 
> That socket would be used to issue control commands:
>     ADD [sim name] [Address] [Port]
>     REMOVE [sim name]
>     RESET

You want to create and remove phonesim modems on the fly? Why?  That
seems utterly pointless.

Regards,
-Denis