This is GNU CSSC, a workalike for the source code control system SCCS.
It is based on the MySC package by Ross Ridge.

SCCS commands implemented this package are: admin, cdc, delta, get,
prs, prt, sccsdiff, rmdel, sact, unget and what.  Not all options and
capabilities of the commands have been implemented yet, and the comb,
val and vc commands are not provided at all.

Unimplemented features include consistency checking (admin -h),
ignored deltas (delta -g), printing the differences after a delta
(delta -p), l-files (get -l), and getting a delta by sequence number
(get -a).  Some features like including and excluding deltas (get -i
-x) have been implemented but not extensively tested.

FreeBSD port made by Oliver Fromme <olli@fromme.com>