===================================================================
RCS file: /cvs/mandoc/mdoc.7,v
retrieving revision 1.279
retrieving revision 1.282
diff -u -p -r1.279 -r1.282
--- mandoc/mdoc.7	2019/07/15 19:20:30	1.279
+++ mandoc/mdoc.7	2020/06/25 20:45:09	1.282
@@ -1,7 +1,7 @@
-.\"	$Id: mdoc.7,v 1.279 2019/07/15 19:20:30 schwarze Exp $
+.\"	$Id: mdoc.7,v 1.282 2020/06/25 20:45:09 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
-.\" Copyright (c) 2010, 2011, 2013-2018 Ingo Schwarze <schwarze@openbsd.org>
+.\" Copyright (c) 2010, 2011, 2013-2020 Ingo Schwarze <schwarze@openbsd.org>
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above
@@ -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 15 2019 $
+.Dd $Mdocdate: June 25 2020 $
 .Dt MDOC 7
 .Os
 .Sh NAME
@@ -449,6 +449,7 @@ in the alphabetical
 .It Ic \&Ss Ta subsection header (one line)
 .It Ic \&Sx Ta internal cross reference to a section or subsection
 .It Ic \&Xr Ta cross reference to another manual page: Ar name section
+.It Ic \&Tg Ta tag the definition of a Ar term Pq <= 1 arguments
 .It Ic \&Pp Ta start a text paragraph (no arguments)
 .El
 .Ss Displays and lists
@@ -1202,7 +1203,8 @@ Close a
 block.
 Does not have any tail arguments.
 .It Ic \&Dd Cm $\&Mdocdate$ | Ar month day , year
-Document date for display in the page footer.
+Document date for display in the page footer,
+by convention the date of the last change.
 This is the mandatory first macro of any
 .Nm
 manual.
@@ -1847,8 +1849,8 @@ instead.
 Format a hyperlink.
 .Pp
 Examples:
-.Dl \&.Lk http://bsd.lv \(dqThe BSD.lv Project\(dq
-.Dl \&.Lk http://bsd.lv
+.Dl \&.Lk https://bsd.lv \(dqThe BSD.lv Project\(dq
+.Dl \&.Lk https://bsd.lv
 .Pp
 See also
 .Ic \&Mt .
@@ -2548,6 +2550,49 @@ Table cell separator in
 .Ic \&Bl Fl column
 lists; can only be used below
 .Ic \&It .
+.It Ic \&Tg Op Ar term
+Announce that the next input line starts a definition of the
+.Ar term .
+This macro must appear alone on its own input line.
+The argument defaults to the first argument of the first macro
+on the next line.
+The argument may not contain whitespace characters, not even when it is quoted.
+This macro is a
+.Xr mandoc 1
+extension and is typically ignored by other formatters.
+.Pp
+When viewing terminal output with
+.Xr less 1 ,
+the interactive
+.Ic :t
+command can be used to go to the definition of the
+.Ar term
+as described for the
+.Ev MANPAGER
+variable in
+.Xr man 1 ;
+when producing HTML output, a fragment identifier
+.Pq Ic id No attribute
+is generated, to be used for deep linking to this place of the document.
+.Pp
+In most cases, adding a
+.Ic \&Tg
+macro would be redundant because
+.Xr mandoc 1
+is able to automatically tag most definitions.
+This macro is intended for cases where automatic tagging of a
+.Ar term
+is unsatisfactory, for example if a definition is not tagged
+automatically (false negative) or if places are tagged that do
+not define the
+.Ar term
+(false positives).
+When there is at least one
+.Ic \&Tg
+macro for a
+.Ar term ,
+no other places are automatically marked as definitions of that
+.Ar term .
 .It Ic \&Tn Ar word ...
 Supported only for compatibility, do not use this in new manuals.
 Even though the macro name
@@ -2912,6 +2957,7 @@ then the macro accepts an arbitrary number of argument
 .It Ic \&St  Ta    \&No     Ta    Yes      Ta    1
 .It Ic \&Sx  Ta    Yes      Ta    Yes      Ta    >0
 .It Ic \&Sy  Ta    Yes      Ta    Yes      Ta    >0
+.It Ic \&Tg  Ta    \&No     Ta    \&No     Ta    <2
 .It Ic \&Tn  Ta    Yes      Ta    Yes      Ta    >0
 .It Ic \&Ud  Ta    \&No     Ta    \&No     Ta    0
 .It Ic \&Ux  Ta    Yes      Ta    Yes      Ta    n
@@ -3039,17 +3085,6 @@ The following problematic behaviour is found in groff:
 .Pp
 .Bl -dash -compact
 .It
-.Ic \&Dd
-with non-standard arguments behaves very strangely.
-When there are three arguments, they are printed verbatim.
-Any other number of arguments is replaced by the current date,
-but without any arguments the string
-.Dq Epoch
-is printed.
-.It
-.Ic \&Lk
-only accepts a single link-name argument; the remainder is misformatted.
-.It
 .Ic \&Pa
 does not format its arguments when used in the FILES section under
 certain list types.
@@ -3057,9 +3092,6 @@ certain list types.
 .Ic \&Ta
 can only be called by other macros, but not at the beginning of a line.
 .It
-.Ic \&%C
-is not implemented (up to and including groff-1.22.2).
-.It
 .Sq \ef
 .Pq font face
 and
@@ -3109,10 +3141,16 @@ but produces large indentations.
 .Xr tbl 7
 .Pp
 The web page
-.Lk http://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language"
+.Lk https://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language"
 provides a few tutorial-style pages for beginners, an extensive style
 guide for advanced authors, and an alphabetic index helping to choose
 the best macros for various kinds of content.
+.Pp
+The manual page
+.Lk https://man.voidlinux.org/groff_mdoc "groff_mdoc(7)"
+contained in the
+.Dq groff
+package documents exactly the same language in a somehwat different style.
 .Sh HISTORY
 The
 .Nm