which copies the init stuff (whatever it is) from store to /persist
instead of making liminix-rebuild have to know what the files are.
This is principally to ease making a system configuration in /mnt or
similar when operating in a rescue/recovery scenario, and we
don't want to liminix-rebuild because it will reboot
systemconfig (a.k.a "activate") is run from the initramfs. Converting
it from a shell script to an executable means it doesn't depend on
there being a shell in the initramfs
the jffs2 filesystem contains only /nix/store and a script which is
run in early init (initramfs) and is responsible for recreating
"traditional" directories (/bin /etc/**/* /var &c) based on the
configuration.
this is tested only in qemu so far and could use some cleanup
