pic?  I've never used it.

>  pic filename | troff, it doesn't work.
troff is used to drive a printing press/type setter (T=Typeset).
The big problem is how to convert the output of troff?nroff into
a form that (1) drives our displays, or (2) drives our postscript
printer.   
In theory something like this should work on some machines...
	pic smiley.pic|troff|psroff -t >smiley.ps
	netlp postscript smiley.ps
could work.
----------------smiley.ps--------------
.PS
define smile %
a = $1
circle radius a at 0,0
arc cw radius a*.75 from a*.5,-a*.25 to -a*.5,-a*.25
"\(bu" at a*.33,a*.25
"\(bu" at a*-.33,a*.25
%
.PE
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