I just realized I can't find the original code on this guy's website but I have the extracted Amiga disk image from a public domain disk circulated at the time... so, here's the annotated 1987 K&R C code on pastebin for comparison:

RT1.C http://pastebin.com/67KWYV3p

RT2.C http://pastebin.com/pc3Uq2Xd

RT3.C http://pastebin.com/v4Qx0gTD