[iohead]

Well, V7 UNIX is rather arbitrary as a reference point for comparison. There was what we now call as V1 UNIX, which would be circa 1971/72, so that's certainly 50+ years old. Compared to what's shown in the article, some of the data structure fields and constants would be different and/or missing in the still earlier versions. DIRSIZ would be 8, for example.

[musicale]

Well the author refers to Bach's book (though I thought that was System V?) Another option would be V6 with Lions' commentary.