Connection handler and btmgmt/bluetoothctl

Hi,

I am implementing my own GATT server using the "tool/gatt-service.c" as example. Create services and read/write characteristics is not a problem, but I need a way to track connection and disconnection of clients.
Is there any way to make a handler or callback function that trigger when a client connects/disconnects to my server?


Another question about best practice. For the moment I use "btmgmt" to configure my daemon. However, the "bluetoothctl" binary seems to be a more stable alternative except that i cannot find any way to do the "le on" command as in "btmgmt".
Is there any way to activate the low energy option with bluetoothctl?

Regards,

Clément.