Re: [ptxdist] /usr merge

["Enrico Weigelt, metux IT consult" <enrico.weigelt@gr13.net>]

On 11.04.2017 12:07, Michael Olbrich wrote:

Hi,

> I've just pushed a large series of commits for /usr merge. This means that
> /bin, /sbin and /lib are now symlinks to the corresponding directories in
> /usr. All files are installed accordingly.

Just curious: what's the actual problem to solve ?

For my embedded projects, I haven't had an actual usecase for having
them separated, but on server systems lots of them over the past 20yrs.

Note that this separation indeed has serious reaons: separating the
base system (IOW: everything required to boot up at least to single
user mode and mount /usr - whereever it might come from). Most of the
practical usecases might be obsolete now (eg. storage is so cheap that
people rarely have the need to share /usr within clusters, etc), but
still there're lots of systems out there relying on that (maybe quite
irrelevant to ptxdist, but certainly for standard like Debian)

I'm personally agnostic to that, but I've already seen such setups
(eg. having /usr on separate SDcard) in embedded systems. So, it seems
better if that remains configurable.

> I'm not going to rehash all the arguments for this. My main motivations
> are:
> - It's where the big distros are going, so it's better tested in the long
>   term.

Note that this already caused a lot of trouble there. (eg. there've
been huge flamewars @debian). IIRC that all started w/ the systemd
mess, which suddenly introduced hard dependencies to things in /usr -
the reaction of Lennart+friends was just ranting aaginst who relies
on the separation.

> - We've had several problems in the past where programs where searched in
>   the wrong location. And busybox didn't make that any easier.

Correct me if I'm wrong, but isn't that what $PATH is for ?

> How it works in PTXdist:
> - install_copy and friends will transparently move files to /usr where
>   appropriate. So if you have packages that install files to /bin etc. it
>   should just work. If not, please sent a mail to this list.

I really have a bad feeling about such magic in existing commands,
which now suddenly change semantics. At least that should be
configurable.


--mtx


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