How does dmesg(8) information survive a reboot ?

[Ricardo Branco]

Hi!

I've just tried this Frenzy Live-CD at http://frenzy.org.ua/eng/ a few hours 
ago. It's based on FreeBSD 6.1-STABLE. Then I rebooted into my FreeBSD 
6.1-RELEASE box and suddenly dmesg(8) now outputs the content from the 
previous 2 sessions with the live-CD and my current session with the one I 
have installed. This is great. I have seen those "Rebooting..." lines but 
I've always thought they were written to /var/log/dmesg* right before the 
actual reboot with dmesg(8) somehow retrieving them at the next boot. What 
is the black magic here?