-// Mark all reachable packages with "pkgDepCache::StateCache.Marked=1"
-// the root-set are all essential packages+everything that was not
-// installed automatically
-//
-// If InRootSetFunc is set, it will be called for each PkgIterator. This
-// is usefull for clients that have there own idea about the root-set
-//
-// Everything that is not reach can be removed
-bool pkgMarkUsed(pkgDepCache &Cache);
-bool pkgMarkUsed(pkgDepCache &Cache, InRootSetFunc &f);
-