[groff] 05/18: [docs]: Clarify use of \|, \^, --- in font files.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 0fd8177f87a027f66156482cd70702b053cbdaa6
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Tue Aug 17 06:20:56 2021 +1000

    [docs]: Clarify use of \|, \^, --- in font files.
---
 doc/groff.texi       |  8 ++++++--
 man/groff_font.5.man | 14 ++++++++++++--
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/doc/groff.texi b/doc/groff.texi
index 6106a6f..fb999dd 100644
--- a/doc/groff.texi
+++ b/doc/groff.texi
@@ -18093,7 +18093,9 @@ if @var{name} is a single character@tie{}@var{c}, it 
corresponds to the
 @code{troff} input character@tie{}@var{c}.  Otherwise, it must be of the
 form @samp{\@var{name}} where @var{name} is at least one character; it
 then corresponds to the GNU @code{troff} special character escape
-sequence @samp{\[@var{name}]}.
+sequence @samp{\[@var{name}]},
+or the one-sixth and one-twelfth unbreakable space escape sequences,
+@code{\|} and @code{\^} (``thin'' and ``hair'' spaces, respectively).
 @c XXX: Commented out because the charXXX feature is very legacy, and as
 @c noted below, discouraged in font description files.
 @c
@@ -18110,7 +18112,9 @@ sequence @samp{\[@var{name}]}.
 @c different (input) character sets.
 A name consisting of three minus signs, @samp{---}, is special and
 indicates that the glyph is unnamed: such glyphs can only be accessed by
-means of the @code{\N} escape sequence in @code{troff}.
+means of the @code{\N} escape sequence in @code{troff}.  A special
+character named @samp{---} can still be defined using @code{char} and
+similar requests.
 
 The form of the @var{metrics} field is as follows.
 
diff --git a/man/groff_font.5.man b/man/groff_font.5.man
index 45e0a06..cc65cd7 100644
--- a/man/groff_font.5.man
+++ b/man/groff_font.5.man
@@ -691,16 +691,26 @@ it then corresponds to the
 .I groff
 special character escape sequence
 .BI \[rs][ name ]\c
-\&.
+\&,
+or the one-sixth and one-twelfth unbreakable space escape sequences,
+\[rs]| and \[rs]\[ha]
+(\[lq]thin\[rq] and \[lq]hair\[rq] spaces,
+respectively).
 .
 A name consisting of three minus signs,
 .RB \[lq] \-\-\- \[rq],
-is special and indicates that the glyph is unnamed:
+indicates that the glyph is unnamed:
 such glyphs can only be accessed by means of the
 .B \[rs]N
 escape sequence in
 .IR troff . \" generic; \N is portable
 .
+A special character named
+.RB \[lq] \-\-\- \[rq]
+can still be defined using
+.B .char
+and similar requests.
+.
 .
 .P
 The form of the