I have two or more 4G dongles connected via USB. I have set up multiple configuration files (one for each provider), but short of a visual inspection (which for this project won't be possible in the field) I have no way of knowing which SIM in which dongle is connected to which mobile provider.
Is there a way of interrogating the dongle from the command line - perhaps using the chat command - to ask it which mobile provider it is connected to? Obviously smartphones can do this - they display it, after all. Would this be possible with a dongle?
By the way, this would be before telling the modem to connect to the provider's APN, so I can then call pppd with the provider-appropriate config file.