ref: e4322f4dffdea1ac61d67e2f0852982c65f5e98d dir: /src/execfs/rules/
# mount -q /srv/magic /usr/web/magic /man2html/([0-9])/([a-zA-Z0-9\.]+) troff -manhtml /sys/man/\1/\2 | troff2html -t '\2(\1)'