The "sed" man page has a "FIXME" in it, despite the fact that
"sed" has been around for over two decades! Har Har. The "See Also"
section has a "XXX" and a reference to "regex(5)" which doesn't exist.
(There is a regex(7) which would be better than that. It could also
refer to "GNU regex manual" (which should come in some RPM too).
sed may have been around for awhile, but the FIXME refers to GNU regex's that
still quite new. Deferred.