Re: [gentoo-dev] Help testing ebuilds? golang/Fabio load balancer

["Michał Górny" <mgorny@gentoo.org>]

W dniu sob, 11.11.2017 o godzinie 12∶31 -0500, użytkownik Michael
Orlitzky napisał:
> > > and a meta-question,
> > > 
> > >   c) Seriously, empty directories are undefined behavior?
> > 
> > ...and how could they be defined if a directory can be installed by
> > multiple packages and has no explicit ownership?
> 
> I see the problem, but the package manager knows which packages are
> using a given directory. (Portage does, and it is at least easy to
> record that information.)
> 
> Empty directories could be installed normally, and then during an
> unmerge, the package manager could check to see if the empty directory
> is used by any package. If it is, leave it -- if not, remove it. You
> might object that this would slow down the unmerge process, but a clever
> lookup scheme would let you map directory names to packages quickly.
> 
> In fact, such a lookup scheme is already implemented in the filesystem
> itself, leading me full circle to the following idea: if the package
> manager is about to install an empty directory, it could create the
> ".keep" file itself. Then "ls -a $dir" is your lookup function that
> determines whether or not a directory is in use by a package.

What about a directory that is installed empty by multiple different
packages, and non-empty by some other packages?

> Having the package manager handle empty directories solves two problems,
> 
>   1) Use of "keepdir" is inconsistent, because portage is happy to let
>      you create an empty directory without it (even though that
>      operation is illegal).

It is not. It is just not guaranteed to be meaningful.

> 
>   2) The build systems of many packages will create empty directories
>      during "make install", and it's unreasonable to expect developers
>      to "keepdir" them all.

Not all of those directories are really meaningful.

> Essentially,we have two commands to create a directory, "dodir" and
> "do-empty-dir" (which we call "keepdir"). The latter is only necessary
> due to an implementation detail, so it doesn't belong in the user
> interface -- the PM should figure out what to do.
> 
> As far as the actual implementation goes, I'm not sure that
> automatically-generated ".keep" files are better than having the package
> manager maintain its own database. The latter would be more complex, but
> would avoid littering everyone's filesystems with ".keep" files.

Do you care enough to spec this properly, introduce EAPI-conditional
behavior for it and prepare patches for the package managers?

-- 
Best regards,
Michał Górny