[arch-general] How to find if a file belongs to a installed package?

[Hector Martinez-Seara]

Hi,
I have been looking but I haven't found a solution to check if a given
file in my system belongs to any of my Installed packages.

For example, in all my 3 archllinux machine I have a directory named:
/usr/lib/libreoffice/basis3.3    85Mb

I would not expect to have this directory as I'm fully updated and my
current libreoffice is 3.4. Accordingly there also exists the
directory:
/usr/lib/libreoffice/basis3.4        335Mb

I'm not an expert in the libreoffice package and therefore blindly
removing the first, without knowing if it is really needed or it is
just some directory during the updates, makes me feel unconformable.

The command in question should be able not only to check repository
packages but also locally installed ones although if it is not
possible with the first will be enough.
Thanks in advance,
Hector
-- 
Hector Martínez-Seara Monné
mail: hseara at gmail.com
Tel: +34656271145
Tel: +358442709253