Global USE flags

Flag	Description	Packages
selinux		4
test		2

Category USE flags

sys-fs

Flag	Description	Packages
static-libs		2

virtual

Flag	Description	Packages
systemd		3

Local USE flags

sys-auth

elogind

Flag	Description
acl
audit
cgroup-hybrid	Use hybrid cgroup hierarchy instead of unified (OpenRC's default).
debug
doc
pam
policykit

sys-fs

eudev

Flag	Description
introspection
kmod	enable module loading through libkmod
rule-generator	install legacy rule generator rules and support scripts - note that the functionality within was dropped from <pkg>sys-fs/udev</pkg> as it is not stable in all cases; use at your own risk
split-usr

libudev-zero

Flag	Description
hotplug
static

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