For a requirement to generate per-PC license keys, I need some code which will return a stable and (near) unique key on any PC. It doesn't have to be guaranteed unique, but close. It does need to be reasonably stable though, so that a given PC always generates the same result unless the hardware is substantially changed.
This is for a Windows application, using wxWidgets but a Win32 or other option is fine.
I was thinking about MAC address but what about laptops which can routinely disable the network card in power-saving mode? I came across GetCurrentHwProfile but it doesn't quite look like what I want?
I would just go with the MAC address method; when the wireless / LAN cards are turned off they still show up in Network Connections. You should therefore still be able to get the MAC.
Consider this: Any time you'd be able to contact your webserver or whatever you're cataloging these IDs with, the user is going to have to have some form of network card available.
Oh, and you might be able to use CPU serial number of the customer's computer supports it.