Hi Damian, > > Sadly, I was under the 35 year impression you could. But in my > > letterhead where I use > > > > .ti +5i > > > > to offset the date, I realised nroff/groff(tty) and troff/groff(a4) > > are only approximately correct.
I agree with Larry. It's easy to see that groff's PostScript output spaces the two `|' five inches of 72 points per inch apart. $ groff >t.ps | .ti +5i | $ grep /F0 t.ps /F0 10/Times-Roman@0 SF(|)72 12 Q(|)432 24 Q 0 Cg EP $ expr 432 - 72 360 $ expr 5 \* 72 360 nroff here is doing that at 10 characters per inch, or 10 "pitch", as we'd expect from a typewriter. Cheers, Ralph.