From the rendered manual that is linked from TFA https://dspinellis.github.io/unix-v4man/v4man.pdf https://dspinellis.github.io/unix-v4man/v4man.pdf > This m

From the rendered manual that is linked from TFA https://dspinellis.github.io/unix-v4man/v4man.pdf https://dspinellis.github.io/unix-v4man/v4man.pdf > This manual was set by a Graphic Systems phototypesetter driven by the troff formatting program operating under the UNIX system. The text of the manual was prepared using the ed text editor.