[Groff] How to set the exact top and bottom margin with -mm ?

[Thomas Baruchel]

Brest, le samedi 30 septembre

Hi, I just discovered the -mm macros after having always written raw troff code
(sometimes I used -ms macros :-). Is it possible to set the exact value for
the top and bottom space ?
I use no header, and have a bottom with my page number: I would like to specify,
say 72p, between the physical top of the page and the top of my first line of
text, and 72p between the baseline of my number page and the physical bottom
of the page. What can I do ?

+-------------------+
|    <72p>          |  <-- margin (72p)
| Hello this is a   |  <-- no header
| very tiny par...  |
|   [...]           |
|   [...]           |
|   [...]           |
|   [...]           |
|   [...]           |
|   [...]           |
|   [...]           |
| end of my text    |
|                   |
|   Page 1          |  <-- bottom of my page
|    <72p>          |  <-- margin (72p)
+-------------------+

-- 
   .~.   Thomas Baruchel
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