I've been looking into the history of the nl command lately, which has gotten me
curious as to what facilities folks have used at various points in UNIX history for line
numbering.
The earliest version of nl I've found is in System III, and it does not derive from
Research, PWB, or CB. Neither does it come from BSD, although BSD has the num command
which, according to the source commentary, aims to replicate the '#' behavior of
ex.
Were there any other facilities for printing back arbitrary lines from a file with line
numbers?
Also, would anyone happen to know if the above appearance of nl might have been from the
USG line given none of the others feature it? It neither seems to be in V8-V10. nl has
managed to find its way into the POSIX standard, so it definitely has some staying power
wherever it came from.
- Matt G.