explain escaping of end-of-sentence characters;

missing info reported by Ian <ropers at gmail dot com> on misc@

2 files changed, 17 insertions, 4 deletions

diff --git a/mdoc.7 b/mdoc.7
index 40e4ca84..deca4ba8 100644
--- a/mdoc.7
+++ b/mdoc.7
@@ -1,4 +1,4 @@
-.\"	$Id: mdoc.7,v 1.278 2019/04/24 13:15:00 schwarze Exp $
+.\"	$Id: mdoc.7,v 1.279 2019/07/15 19:20:30 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010, 2011, 2013-2018 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: April 24 2019 $
+.Dd $Mdocdate: July 15 2019 $
 .Dt MDOC 7
 .Os
 .Sh NAME
@@ -3005,6 +3005,13 @@ in the same way as a plain
 .Sq \&|
 character.
 Using this predefined string is not recommended in new manuals.
+.Pp
+Appending a zero-width space
+.Pq Sq \e&
+to the end of an input line is also useful to prevent the interpretation
+of a trailing period, exclamation or question mark as the end of a
+sentence, for example when an abbreviation happens to occur
+at the end of a text or macro input line.
 .Ss Font handling
 In
 .Nm
diff --git a/roff.7 b/roff.7
index 108e62d9..f129750b 100644
--- a/roff.7
+++ b/roff.7
@@ -1,4 +1,4 @@
-.\"	$Id: roff.7,v 1.113 2019/07/01 23:30:16 schwarze Exp $
+.\"	$Id: roff.7,v 1.114 2019/07/15 19:20:30 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010-2019 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: July 1 2019 $
+.Dd $Mdocdate: July 15 2019 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -315,12 +315,18 @@ delimiters
 The proper spacing is also intelligently preserved if a sentence ends at
 the boundary of a macro line.
 .Pp
+If an input line happens to end with a period, exclamation or question
+mark that isn't the end of a sentence, append a zero-width space
+.Pq Sq \e& .
+.Pp
 Examples:
 .Bd -literal -offset indent -compact
 Do not end sentences mid-line like this.  Instead,
 end a sentence like this.
 A macro would end like this:
 \&.Xr mandoc 1 \&.
+An abbreviation at the end of an input line needs escaping, e.g.\e&
+like this.
 .Ed
 .Sh REQUEST SYNTAX
 A request or macro line consists of: