Re: [Groff] Optional backward compatibility to Bell Labs

[Eric S. Raymond]

Werner LEMBERG <address@hidden>:
> 
> > +.\" Emulate Bell Labs localisms by setting -r bell=1 on the command
> > +.\" line.
> 
> Thanks.  Shall this be documented?  Then I would like to see patches
> for groff_ms.man, groff.texinfo, and NEWS.

Here:

Diffs between last version checked in and current workfile(s):

--- NEWS.~1.233.~       2007-01-12 08:31:57.000000000 -0500
+++ NEWS        2007-02-01 02:53:08.000000000 -0500
@@ -7,7 +7,10 @@
 Groff
 -----
 
+o Eric S. Raymond contributed support for ancient Bell Labs localisms .SC,
+  .UC, .P1, and .P2 in ms when the command-line switch -r bell is given.
+
 o Fabrice Ménard contributed locales support.  In particular, it is now
   possible to get French localization of the main macro packages (-ms, -mm,
   -me, and -mom, but not -man and -mdoc which are localized differently) by
--- doc/groff.texinfo.~1.254.~  2006-12-31 00:01:53.000000000 -0500
+++ doc/groff.texinfo   2007-02-01 03:19:09.000000000 -0500
@@ -4411,7 +4411,23 @@
 A cover sheet macro
 @end table
 
+Emulations of a few ancient Bell Labs macros can be re-enabled with
+the @code{groff} command-line option @code{-r bell}.  They are
address@hidden, @code{UC}, @code{P1}, and @code{P2}.
+
+These are not enabled by default because (a) they were not documented,
+in the original @code{ms} manual, and (b) the @code{P1} and @code{UC}
+macros collide with different macros with the same names in the
+Berkeley version of @code{ms}.
+
+These @code{groff} emulations are sufficient to give back the
+1976 Kernighan & Cherry paper @cite{Typsetting Mathematics - User's
+Guide} its section headings, and restore some text that had gone
+missing as arguments of undefined macros.  No warranty express or
+implied is given as to how well the typographic details these produce
+match the original Bell Labs macros.
+
 @c ---------------------------------------------------------------------
 
 @node Additional ms Macros,  , Missing ms Macros, Differences from AT&T ms
--- tmac/groff_ms.man.~1.18.~   2006-03-05 12:03:40.000000000 -0500
+++ tmac/groff_ms.man   2007-02-01 03:21:10.000000000 -0500
@@ -1298,8 +1298,32 @@
 rather than silently to ignore them.
 .
 .IP \(bu
-Bell Labs localisms are not implemented.
+Some Bell Labs localisms are not implemented by default.  However, by
+giving the command-line option "-r bell" you can enable
+implementations of the archaic Bell Labs macros 
+.BR SC ,
+.BR UC ,
+.BR P1 ,
+and 
+.BR P2 .
+These are not enabled by default because (a) they were not documented, 
+in the original 
+.IR ms manual ,
+and (b) the
+.B P1
+and 
+.B UC
+macros both collide with different macros in the Berkeley version of
+.IR ms . 
+The 
+"-r bell"
+emulations are sufficient to give back the 1976 Kernighan & Cherry paper
+.I Typsetting Mathematics - User's Guide
+its section headings, and restore some text that had gone missing as
+arguments of undefined macros.  No warranty express or implied is
+given as to how well the typographic details these produce match the
+original Bell Labs macros.
 .
 .IP \(bu
 Berkeley localisms, in particular the
End of diffs.

You might wish to firther modify the coment in s.tmac to reflect the 
fact that .UC also collides with a Berkeley macro.

> > +.if \n[bell] \{\
> 
> This causes a warning with the -ww command line option in case `bell'
> isn't defined.  The right way is to say
> 
>   .if r bell \{\

My education continues...
-- 
                <a href="http://www.catb.org/~esr/";>Eric S. Raymond</a>