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TeX was first released in 1978. BSD UNIX in 1977. I don't know how much of that code is running today, but I'd be very surprised if the methods embodied in that
by robotresearcher 14y ago
TeX was first released in 1978. BSD UNIX in 1977. I don't know how much of that code is running today, but I'd be very surprised if the methods embodied in that code (the patentable parts) have changed very much in 20 years. There may well be chunks of code more than 20 years old in both those widely-used and absolutely relevant systems.
Lots of decades-old C, Fortran and Lisp code compiles and runs just fine today. Code has been quite well decoupled from architecture since the 1970s, if you choose to write it that way.