I have a Debian Jessie Linux system with an internal RTC clock which the user can adjust or change. It may or may not be connected to external IP and therefore may or may not have access to NTP. I would like to provide an option in the clock setting UI to "set from NTP" if it is available, but I don't want the system clock to be constantly updated from NTP.
- How can I configure ntpd to be active, but not update the system clock?
- How can I read and display the 'ntp time' (which will be shown along with the system clock)? (C or Python is fine)