[Groff] problem with zero top margin with plain groff

[Matthias Buelow]

Hi folks,

  I've got a problem with trying to achieve a zero top and bottom
margin with plain [tg]roff (no macro package).
The problem is, that with postscript output, it'll always display
ca. 1 inch of white top margin, although to my research of various
documents, the first text line should start right at the physical
beginning of the page (troff/groff references say [tg]roff shouldn't
define any top/bottom margins by itself.)
I use A4 sized paper and explicitly give the line and paper length.
The following trivial example demonstrates the problem (I have used
groff 1.10 and 1.15 so far, I don't have 1.16 available right now):

.po 0i
.ll 20.9903c
.pl 29.7039c
foobar baz

which I format with "groff -Tps filename >filename.ps".
The problem is quite annoying, since I cannot write to the first
inch of paper and the text which normally ought to fit on the sheet
is truncated at the end of paper.  It isn't just the printer, the
problem shows up with a previewer (such as ghostview) aswell...

        --mkb