IP interface name of PPP connection

[Joachim Selke <mail joachim-selke de>]

Hello everyone,

I have set up a PPP connection and would like to retrieve the name of 
its IP interface (typically it is ppp0, but not always).

I have been able to get the name of the IP interface in dispatcher 
scripts using the variable DEVICE_IP_IFACE. However, I did not find a 
way to do this using nmcli ("nmcli -g <FIELD> con show <CONN>").

Does anyone know how to do this?

Best wishes,
Joachim