[groff] 01/07: [ms]: Set footnote line length to AT&T default.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 0c7e84cc3c87407bef0d3de0c7b54ee8d3a47e23
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sun Dec 20 13:39:50 2020 +1100

    [ms]: Set footnote line length to AT&T default.
    
    groff ms has since its initial implementation used a default footnote
    line length of 5/6ths of the text line length; this may correspond to an
    early AT&T ms default (perhaps documented in the 1974 version of the M.
    E. Lesk paper, "Typing Documents on the UNIX System", published by the
    ACM).  However, as early as V6 Unix (1975), AT&T ms actually used a
    footnote line length of 11/12ths of the text line length instead[2].
    
    * tmac/s.tmac: Set default footnote line length to 11/12ths of
      the text line length.
    
    * doc/groff.texi (ms Document Control Settings):
    * doc/ms.ms (Document control registers):
    * NEWS: Document changed default.
    
    Thanks to T. Kurt Bond for the report to the groff mailing list and M.
    Douglas McIroy for the discussion.
    
    [1] https://www.troff.org/using-ms.pdf
    [2] https://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/lib/tmac.s
---
 ChangeLog      | 21 +++++++++++++++++++++
 NEWS           |  5 +++++
 doc/groff.texi |  2 +-
 doc/ms.ms      |  2 +-
 tmac/s.tmac    |  2 +-
 5 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index bc8262c..1ddf064 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,24 @@
+2020-12-20  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       [ms]: Set footnote line length to AT&T default.
+
+       groff ms has since its initial implementation used a default
+       footnote line length of 5/6ths of the text line length; this may
+       correspond to an early AT&T ms default (perhaps documented in
+       the 1974 version of the M. E.  Lesk paper, "Typing Documents on
+       the UNIX System", published by the ACM).  However, as early as
+       V6 Unix (1975), AT&T ms actually used a footnote line length of
+       11/12ths of the text line length instead[2].
+
+       * tmac/s.tmac: Set default footnote line length to 11/12ths of
+       the text line length.
+
+       * doc/groff.texi (ms Document Control Settings):
+       * doc/ms.ms (Document control registers): Document new default.
+
+       [1] https://www.troff.org/using-ms.pdf
+       [2] https://minnie.tuhs.org/cgi-bin/utree.pl?file=V6/usr/lib/tmac.s
+
 2020-12-09  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        Lower new unplanted trap error to 'mac' warning.
diff --git a/NEWS b/NEWS
index 167858f..f616d92 100644
--- a/NEWS
+++ b/NEWS
@@ -113,6 +113,11 @@ o The doc (mdoc) macro package now honors the HY register 
as the an
   furthermore recognizes but ignores the AD string (see above) for
   compatibility with an (man).
 
+o The s (ms) macro package has changed the default footnote line length
+  (\n[FL]) from 5/6ths of the text line length (\n[LL]) to 11/12ths for
+  better compatibility with ms documents prepared with AT&T ms and its
+  descendants.
+
 o The s (ms) macro package has added strings, \*< and \*>, to perform
   subscripting within a paragraph.  They work analogously to the \*{ and
   \*} superscripting strings that have been present in groff ms since
diff --git a/doc/groff.texi b/doc/groff.texi
index 60f7e61..0cdc3bd 100644
--- a/doc/groff.texi
+++ b/doc/groff.texi
@@ -2806,7 +2806,7 @@ Defines the length of a footnote.
 
 Effective: next footnote.
 
-Default: @math{@code{@\n[LL]} * 5 / 6}.
+Default: @math{@code{@\n[LL]} * 11 / 12}.
 @endDefmpreg
 
 @Defmpreg {FI, ms}
diff --git a/doc/ms.ms b/doc/ms.ms
index 88101a3..381e7c4 100644
--- a/doc/ms.ms
+++ b/doc/ms.ms
@@ -255,7 +255,7 @@ Paragraphs  PI      Initial indent  next \(pp       5n
 \^     PD      Space between paragraphs        next \(pp       0.3v
 \^     QI      Quoted paragraph indent next \(pp       5n
 _
-Footnotes      FL      Footnote length next footnote   LL*5/6
+Footnotes      FL      Footnote length next footnote   LL*11/12
 \^     FI      Footnote indent next footnote   2n
 \^     FF      Footnote format next footnote   0
 _
diff --git a/tmac/s.tmac b/tmac/s.tmac
index 6124ced..6c2a90a 100644
--- a/tmac/s.tmac
+++ b/tmac/s.tmac
@@ -1094,7 +1094,7 @@ along with this program.  If not, see 
<http://www.gnu.org/licenses/>.
 .\" happens when the first page begins
 .de par@init
 .if !rLT .nr LT \\n[LL]
-.if !rFL .nr FL \\n[LL]*5/6
+.if !rFL .nr FL \\n[LL]*11/12
 .if !rVS \{\
 .      ie (\\n[PS] >= 1000) \
 .              nr VS (\\n[PS] + 2000)