363f8db139
doc/Gbk-1pg-sfx.mn is already using one half of a sound technique: set the page length to a very large value, guaranteed to overshoot the vertical space required by the document's text. The other half is to, at the end of the document, set the page length to the current vertical position, so that it ends immediately. https://www.gnu.org/software/groff/manual/groff.html.node/Manipulating-Spacing.html