> Or in other word, it is enough to only look at /etc/portage/repos.conf? No
> In general, an overlay is a repository, i.e., a valid tree layout for the Yes > - can the profiles in a repository different from DEFAULT be selected? Yes > - is the package.mask file apply only on the packages of that repository, or > on every packages of > every repositories listed in /etc/portage/repos.conf? Actually, I can't remember the correct answer right now, but definitelly it have the effect on repos, that states this repo as master. > is such information implicitly inherited from the DEFAULT repository (even > though https://wiki.gentoo.org/wiki//etc/portage/repos.conf states that it > is not)? Usually, that info is inerited from `master` repo of the current repo (that is stated in the layout conf file) > the brother overlay (https://github.com/stefan-langenmaier/brother-overlay) > does not specify > any masters Eeeerm? https://github.com/stefan-langenmaier/brother-overlay/blob/master/metadata/layout.conf#L1 > - when the eclass folder, profiles/arch.list and such are > present, is the data from the DEFAULT repository still implicitly > inherited? I still insist on inheritance from master repo. > - when the eclass folder, profiles/arch.list and such are > present, are they visible globally (i.e., a package from another repository > can use a keyword of the arch.list and inherit from one of the eclass)? AFAIRC, depends on the repos relative priority. > 4. is the "masters" attribute in /etc/portage/repos.conf make the repository > inherit other data than the eclasses? Yes, but that attribut is usually not recommended for general use. > 5. since every repos can have a profiles/categories file, is the file > /etc/portage/categories obsolete (or should it be)? Why?