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Date: Tue, 29 Sep 2015 11:40:04 +0200 (CEST)
From: Julius Schmidt <aiju@phicode.de>
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Subject: troff(1): read in program
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Is there any way to display a program in troff -ms that's read in from a 
file?

The best I could come up with is the one below, but that seems to drop \ 
for some reason.

.P1
.eo
.so aijupins11
.ec
.P2