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

[Michael Orlitzky]

On 11/10/2017 04:36 PM, Damo Brisbane wrote:
>
> Re for...keepdir, I found removing it then the /var/log/fabio folders
> were not getting created, so keeping it in there.

You need to tell the ebuild to create that directory one way or another.
The "dodir" function will create the directory, but without the ".keep"
file inside of it. However that may be "illegal" in this case; see below.


> http://www.calculate-linux.org/main/en/using_ebuild, says this of *keepdir*:
>
> *Creates (if necessary) a |.keep| file in the given directory so that it
> isn't auto-cleaned. Never create a |.keep| file yourself. If Portage
> changes how |keepdir| works, then creating the file yourself will break
> the package.*

To my knowledge, no package manager will remove a non-empty directory,
nor will it remove anything that the package manager did not itself
create. To me that raises a question: why would I ever want to keep
around an (otherwise empty) directory that was created by the package
manager?

I found this,

  https://dev.gentoo.org/~ulm/pms/head/pms.html#x1-15100013.2.2

which states

  Behaviour upon encountering an empty directory is undefined. Ebuilds
  must not attempt to install an empty directory.

Certainly "keepdir" will make the directory non-empty, but with the
additional (unwanted) side-effect that the directory won't be removed
when the package is uninstalled. Thus "keepdir" doesn't seem like it was
intended to address that technicality. So, I have two questions now...

  a) When would you want to use keepdir?

  b) What's the right way to prevent a directory from being empty? Touch
     a dummy file?

and a meta-question,

  c) Seriously, empty directories are undefined behavior?