its kernel that does the leap second handling, ntpd just informs it of upcoming leaps https://elixir.bootlin.com/linux/v6.4.1/source/kernel/time/ntp.c#L406 htt

its kernel that does the leap second handling, ntpd just informs it of upcoming leaps https://elixir.bootlin.com/linux/v6.4.1/source/kernel/time/ntp.c#L406 https://elixir.bootlin.com/linux/v6.4.1/source/kernel/time/n... sure leap smearing could be considered compatible with posix in the sense that posix does afaik not require any level of accuracy from clocks, so even something silly like xkcd 2266 could be considered posix compatible https://xkcd.com/2266/ https://xkcd.com/2266/