The disk image here contains a 7th Edition UNIX system which has had some Y2K bug fixes applied by Alexey Chupahin . I don't have exact details on what he fixed, but here are some comments: You just get file containing Unix7 Y2k system. 2 new utilities come with it: "date2" Y2k command and "sl" string command editor with stack of previously entered command. format of command: date2 year month day [hour minutes [sec]] #date2 2000 4 8 11 45 for example. Unfortunatly, I find a bug in sl command too late, sorry (it is not fatal, but unefficient). I've fixed it in BSD Y2k version image that I patched yet. You may copy binary sl file from BSD to Unix7 and it will work or recompile source using Unix7 cc compiler.