[gentoo-dev] Stow (Was: Why the FHS can't be followed)

[Wout Mertens <wmertens@gentoo.org>]

Hey there,

On 2 Jul 2002, Fuper wrote:

> On Tue, 2002-07-02 at 20:54, Luke Ravitch wrote:

> Now, as for Stow -- I beat you up for not loving Stow!  I may find some
> drawbacks in the future that are not apparent to me now but it seems to
> me that the tiny Stow script makes it possible to install, upgrade, and
> remove software packages without depending on a database to track all of
> the files.  For example, I can answer the following questions without
> reference to an rpm or dpkg (or portage) database:
[...]

I agree, stow is cool and at work we use it to maintain our 12GB
/usr/local tree that is exported over nfs to our workstations.
Some drawbacks, however:

- You have a slight speed loss because of the symlinking adding
  extra lookups. Luckily, Linux has very good caching :)

- Some packages hate it when you symlink stuff; e.g. sudo needs its
  sudoers file to be a regular file. Granted, this is a configuration file
  and as such may not need to be symlinked in a general gentoo context, so
  this could be solved by just creating a regular file in the
  pkg_postinst.

- stow -R can grind your server to a screeching halt if you have many
  files. I'm sure this is solveable by rewriting the code a little, and I
  don't know if recent versions have trouble with it since we don't try it
  anymore ;)

- You have a lot of symlinks in your /usr, which makes ls -l a bit less
  attractive to look at. Of course, there's still ls -lL ;-)

I've been considering nagging to drobbins about changing Portage so that
merging actually means
'Copy package to /var/db/packages/<cat>/<pkg>/files/ and symlink everything'
and unmerging means 'remove the symlinks'. Portage would then need a
purge option to remove the package files altogether.

This would have the advantage that you can always revert to a certain
version of a package with certainty, since no files are removed from the
previous package. And you see where a file comes from really quickly by
looking at the symlink, which is very useful.

And actually, I think it would be possible to let portage optionally have
that feature, because the only thing it changes is where the files are
installed and what merge and unmerge do. All the rest would stay the
same. That way, people who want it can turn it on and the rest aren't
bothered.

Thoughts?

Wout.