id	summary	reporter	owner	description	type	status	priority	milestone	component	version	severity	resolution	keywords	cc
4848	make /lib, /bin, /sbin symlinks to their conterpart in /usr	Xi Ruoyao	lfs-book	"Support of ""split-usr"" configuration is deprecated in systemd-248, and likely to be removed in systemd-249.

Fedora and Arch have already made the move.

Specific to LFS, the main advantage of the move is we can delete all `mv /usr/lib/libfoo.so.* /lib && ln -sfv ../../lib/$(...) /usr/lib/libfoo.so` stuff.  The main disadvantage is we'll have to use an initramfs if `/usr` is somewhere on network (but I doubt if there is really someone using LFS/BLFS this way).

It's planned to make the move only for systemd, for now.  The steps:

* [x] rewrite section 4.2 and section 7.5.  In section 4.2 we'll set up `{/usr,}/{lib,lib64,bin,sbin}`, and the references to them should be removed in 7.5.  For consistency both sysv and systemd should be changed: the revisions share a same section 7.5, but section 4.2 would be different
* [x] modify section 4.3 for the changes of 4.2
* [x] remove `-Dsplit-usr=true` in systemd
* [x] mark all `mv /usr/lib/libfoo.so.* /lib ...` commands with `revision=""sysv""`, in LFS
* [x] build and test LFS
* [ ] mark all `mv /usr/lib/libfoo.so.* /lib ...` commands with `revision=""sysv""`, in BLFS"	task	new	normal	10.2	Book	systemd	normal