heirloom-doctools (classic implementation of the troff tools)

The Heirloom Documentation Tools package provides troff, nroff, and 
related utilities to format manual pages and other documents for 
output on terminals and printers. They are portable and enhanced 
versions of the utilities released by Sun as part of OpenSolaris, 
which are a variant of ditroff, which, in turn, descends to the 
historical Unix troff that generated output for the C/A/T 
phototypesetter.

Path settings:
The files get installed into /opt/heirloom . The included
/etc/profile.d/heirloom.sh script sets the PATH to include this
directory _in front of_ the usual paths, so that troff points
to the heirloom version, not the gnu version. To enable this
behaviour, make the /etc/profile.d/heirloom.sh script executable.