Mask everything; selectively unmask

One tip I have is to mask all of the kde svn ebuilds and then selectively unmask the ones I want to use. To accomplish this I did the following hacky command:

find /usr/local/overlays/kde-live/ -iname "*.ebuild" |sed "s/\/usr\/local\/overlays\/kde-live\///g" \
|cut -f1 -d'.'|cut -f1 -d'7'|cut -f1,3 -d'/'|sed "s/$/7/g"|sed "s/^/>=/g"|sort|uniq >> /etc/portage/package.mask

Basically it is a bunch of string manipulation to add entries to you /etc/portage/package.mask. To use a package simply go unmask it by deleting its line in /etc/portage/package.mask

I do this so I can use the amarok-svn ebuild but not tie in all of kde!

Uninstallation

I was using kde-live and was being very unproductive in my coding life, and uninstallation of the kde-meta ebuild is not very straight forward so I did:

emerge unmerge pretend `find /var/db/pkg/kde-base/ -name "*-7" -type d -exec basename {} \;`

This will prevent you from uninstalling your other kde build, if applicable.