The venerable BSD source code typesetter, which I am forking for my own use on macOS, and perhaps for use in other projects. The vgrind command sends its results to a printer using lp; I have added a pprint command which produces PDF files.
This source was gathered from NetBSD.org, using the following commands:
export CVSROOT="anoncvs@anoncvs.NetBSD.org:/cvsroot"
export CVS_RSH="ssh"
cvs checkout -P -d vgrind src/usr.bin/vgrind
No effort is currently being make to track the original, which is decades old.
Makefile and vgrind.sh in the ATTIC are the BSD originals, kept for reference. RETEST contains a test program for regexp.c.