extract.line

I have the man pages for the CWU command extract.line. This program is
part of CWU's grass/tiger/rim package. I have not been able to find the
source code for this command. I got the rest of the package with the
Census1.tar.Z file off of the moon. Was extract.line in that tar file?
Where can I get a copy of extract.line? Thanks in advance, Rich.