[SyncEvolution] Detecting presence of network adapters

Hello, I am considering how to detect the status of network adapter (this will solve MB#8879 as well as some simple presence detection). I prefer to call Bluez/Connman dbus service for this but the problem is there is connman on Moblin and network manager on other distros, there would be some unncessary code duplication to handle both. Or is there any portable underlying APIs that I can refer to directly? -- Regards, Chen Congwu Moblin China Development