Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!ukc!slxsys!jclark!jjc
From: jjc@jclark.UUCP (James Clark)
Newsgroups: comp.text
Subject: Re: problems with "ms" macros
Message-ID: <JJC.91May15095448@jclark.UUCP>
Date: 15 May 91 08:54:48 GMT
References: <dennis.674182199@syzygy> <1991May14.132028.20635@cbnewsl.att.com>
Sender: jjc@jclark.uucp (James Clark)
Organization: None, London, England
Lines: 49
In-Reply-To: npn@cbnewsl.att.com's message of 14 May 91 13:20:28 GMT

In article <1991May14.132028.20635@cbnewsl.att.com> npn@cbnewsl.att.com (nils-peter.nelson) writes:

   Question was how to force break to next column.
   Here is an old trick (from roff):
   text
   text
   text
   .br
   .ne 60
   .br
   .ne 0
   text for start of next column or page.

   The ".ne 60" says "there must be at least 60 lines left
   in this {column|page} for you to start new text here."
   This will never be true (unless you redefine page length)
   and so forces a {column|page} break. The ".ne 0" takes
   effect at the top of {column|page} and says "I changed
   my mind-- put out whatever you have."
   If you find this ungainly, put it in a macro called ".BC".

This solution is unnecessarily complicated.  It would be sufficient
to use

   .br
   .ne 60

(although I would be inclined to use a larger argument than 60v: what
if the document uses a vertical spacing of 10p?).  The effect of 
`.ne 60' is just to do a vertical space of 60v if the distance to the
next trap is less than 60v, and, of course, forward vertical space is
truncated to the distance to the next trap.  In fact `.ne 0' is always
a no-op (unless `ne' has been redefined).

An alternative is to use

   .rs
   .sp 99i

or, if a column should not be started when already at the start of a
column, simply

   .sp 99i

These comments apply to nroff, troff, ditroff and groff.

James Clark
jjc@jclark.uucp
jjc@gnu.ai.mit.edu