sys-apps/fakeroot
A fake root environment by means of LD_PRELOAD and SysV IPC (or TCP) trickery
USE Flags
acl
Global: Adds support for Access Control Lists
debug
Global: Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see http://www.gentoo.org/proj/en/qa/backtraces.xml
nls
Global: Adds Native Language Support (using gettext - GNU locale utilities)
test
Global: Workaround to pull in packages needed to run with FEATURES=test. Portage-2.1.2 handles this internally, so don't set it in make.conf/package.use anymore
static-libs
Global: Build static libraries