No, I don't want to do this from application level hence why I am looking for an alternative. NuttX also has function clock_resynchronize() that should solve the problem with time going backwards but not sure if it has ever been tested and used.
There is an RTC timer driver in drivers/timers that you can use to read to the RTC and receive alarms. That with adjtime() would support a application level solution.
A problem with clock_synchronization() is that it depends on the properties of the RTC so you probably could not make a general solution with it. For example, different RTCs have different time representations, different resolutions, and different behaviors. Many have resolution only to 1 second. Some have sub-second resolution. Different RTCs support different interrupts when events occur like the 1 second increment. Some RTCs support alarms.
