I have a system of 3 or 4 different Linux Ubuntu machines that I would like to be time synced. My plan is to use one of them (let's call it master) as the NTP server that serves time to the 3 other machines (let's call them children).
However, I'd like to get UTC time first from the master and using online servers is not an option (no internet).
I'm currently reading UTC time from an on-board GPS device via C++. Is it possible to set the system time on this processor using C++ and the UTC time provided by a GPS and then use NTP to sync this time to all other children PCs?