===================================================================
RCS file: /cvs/mandoc/roff.7,v
retrieving revision 1.92
retrieving revision 1.101
diff -u -p -r1.92 -r1.101
--- mandoc/roff.7	2017/06/14 22:51:25	1.92
+++ mandoc/roff.7	2018/08/19 17:46:14	1.101
@@ -1,7 +1,7 @@
-.\"	$Id: roff.7,v 1.92 2017/06/14 22:51:25 schwarze Exp $
+.\"	$Id: roff.7,v 1.101 2018/08/19 17:46:14 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
-.\" Copyright (c) 2010,2011,2013-2015,2017 Ingo Schwarze <schwarze@openbsd.org>
+.\" Copyright (c) 2010-2018 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: June 14 2017 $
+.Dd $Mdocdate: August 19 2018 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -86,13 +86,9 @@ character, and, in certain circumstances, the tab char
 The backslash character
 .Sq \e
 indicates the start of an escape sequence, used for example for
-.Sx Comments ,
-.Sx Special Characters ,
-.Sx Predefined Strings ,
+.Sx Comments
 and
-user-defined strings defined using the
-.Sx ds
-request.
+.Sx Special Characters .
 For a listing of escape sequences, consult the
 .Sx ESCAPE SEQUENCE REFERENCE
 below.
@@ -169,34 +165,6 @@ Text decoration is
 recommended for
 .Xr mdoc 7 ,
 which encourages semantic annotation.
-.Ss Predefined Strings
-Predefined strings, like
-.Sx Special Characters ,
-mark special output glyphs.
-Predefined strings are escaped with the slash-asterisk,
-.Sq \e* :
-single-character
-.Sq \e*X ,
-two-character
-.Sq \e*(XX ,
-and N-character
-.Sq \e*[N] .
-.Pp
-Examples:
-.Bl -tag -width Ds -offset indent -compact
-.It Li \e*(Am
-Two-letter ampersand predefined string.
-.It Li \e*q
-One-letter double-quote predefined string.
-.El
-.Pp
-Predefined strings are not recommended for use,
-as they differ across implementations.
-Those supported by
-.Xr mandoc 1
-are listed in
-.Xr mandoc_char 7 .
-Manuals using these predefined strings are almost certainly not portable.
 .Ss Whitespace
 Whitespace consists of the space character.
 In text lines, whitespace is preserved within a line.
@@ -206,7 +174,7 @@ Unescaped trailing spaces are stripped from text line 
 literal context.
 In general, trailing whitespace on any input line is discouraged for
 reasons of portability.
-In the rare case that a blank character is needed at the end of an
+In the rare case that a space character is needed at the end of an
 input line, it may be forced by
 .Sq \e\ \e& .
 .Pp
@@ -665,7 +633,7 @@ produces
 .Pp
 in the input stream, and thus in the output: \fI\^XtFree\^\fP.
 Each occurrence of \e\e$* is replaced with all the arguments,
-joined together with single blank characters.
+joined together with single space characters.
 .Pp
 Since macros and user-defined strings share a common string table,
 defining a macro
@@ -922,15 +890,15 @@ The following
 .Ar font
 arguments are supported:
 .Bl -tag -width 4n -offset indent
-.It Cm B , BI , 3 , 4
+.It Cm B , BI , CB , 3 , 4
 switches to
 .Sy bold
 font
-.It Cm I , 2
+.It Cm I , CI , 2
 switches to
 .Em underlined
 font
-.It Cm R , CW , 1
+.It Cm R , CR , CW , 1
 switches to normal font
 .It Cm P No "or no argument"
 switches back to the previous font
@@ -1037,13 +1005,13 @@ is
 or
 .Sq o
 .Pq odd page ,
-it evaluates to true.
+it evaluates to true, and the
+.Ar body
+starts with the next character.
 .It
 If the first character of
 .Ar condition
 is
-.Sq c
-.Pq character available ,
 .Sq e
 .Pq even page ,
 .Sq t
@@ -1051,11 +1019,24 @@ is
 or
 .Sq v
 .Pq vroff mode ,
-it evaluates to false.
+it evaluates to false, and the
+.Ar body
+starts with the next character.
 .It
 If the first character of
 .Ar condition
 is
+.Sq c
+.Pq character available ,
+it evaluates to true if the following character is an ASCII character
+or a valid character escape sequence, or to false otherwise.
+The
+.Ar body
+starts with the character following that next character.
+.It
+If the first character of
+.Ar condition
+is
 .Sq d ,
 it evaluates to true if the rest of
 .Ar condition
@@ -1346,9 +1327,12 @@ Currently unsupported.
 Temporarily turn off line numbering.
 Currently unsupported.
 .It Ic \&nop Ar body
-Execute the rest of the input line as a request or macro line.
-Currently unsupported.
-.It Ic \&nr Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar expression
+Execute the rest of the input line as a request, macro, or text line,
+skipping the
+.Ic \&nop
+request and any space characters immediately following it.
+This is mostly used to indent text lines inside macro definitions.
+.It Ic \&nr Ar register Oo Cm + Ns | Ns Cm - Oc Ns Ar expression Op Ar stepsize
 Define or change a register.
 A register is an arbitrary string value that defines some sort of state,
 which influences parsing and/or formatting.
@@ -1360,6 +1344,14 @@ below.
 If it is prefixed by a sign, the register will be
 incremented or decremented instead of assigned to.
 .Pp
+The
+.Ar stepsize
+is used by the
+.Ic \en+
+auto-increment feature.
+It remains unchanged when omitted while changing an existing register,
+and it defaults to 0 when defining a new register.
+.Pp
 The following
 .Ar register
 is handled specially:
@@ -1471,7 +1463,7 @@ This is a groff extension and currently ignored.
 .It Ic \&rchar Ar glyph ...
 Remove glyph definitions.
 Currently unsupported.
-.It Ic \&rd Op Ar prompt Op Ar agument ...
+.It Ic \&rd Op Ar prompt Op Ar argument ...
 Read from standard input.
 Currently ignored.
 .It Ic \&recursionlimit Ar maxrec maxtail
@@ -1840,6 +1832,12 @@ is an unpaddable space-sized non-breaking space charac
 .Ss \e\(dq
 The rest of the input line is treated as
 .Sx Comments .
+.Ss \e#
+Line continuation with comment.
+Discard the rest of the physical input line and continue the logical
+input line on the next physical input line, joining the text on
+both lines together as if it were on a single input line.
+This is a groff extension.
 .Ss \e%
 Hyphenation allowed at this point of the word; ignored by
 .Xr mandoc 1 .
@@ -1854,17 +1852,32 @@ instead.
 .Sx Special Characters
 with two-letter names, see
 .Xr mandoc_char 7 .
-.Ss \e*[ Ns Ar name ]
+.Ss \e* Ns Bq Ar name
 Interpolate the string with the
-.Ar name ;
-see
-.Sx Predefined Strings
-and
-.Sx ds .
+.Ar name .
 For short names, there are variants
 .No \e* Ns Ar c
 and
 .No \e*( Ns Ar cc .
+.Pp
+One string is predefined on the
+.Nm
+language level: \e*(.T expands to the name of the output device,
+for example ascii, utf8, ps, pdf, html, or markdown.
+.Pp
+Macro sets traditionally predefine additional strings which are not
+portable and differ across implementations.
+Those supported by
+.Xr mandoc 1
+are listed in
+.Xr mandoc_char 7 .
+.Pp
+Strings can be defined, changed, and deleted with the
+.Ic \&ds ,
+.Ic \&as ,
+and
+.Ic \&rm
+requests.
 .Ss \e,
 Left italic correction (groff extension); ignored by
 .Xr mandoc 1 .
@@ -1874,7 +1887,7 @@ Special character
 .Ss \e/
 Right italic correction (groff extension); ignored by
 .Xr mandoc 1 .
-.Ss \e[ Ns Ar name ]
+.Ss \e Ns Bq Ar name
 .Sx Special Characters
 with names of arbitrary length, see
 .Xr mandoc_char 7 .
@@ -1930,14 +1943,14 @@ Move down by half a line; ignored by
 .Xr mandoc 1 .
 .Ss \ee
 Backslash special character.
-.Ss \eF[ Ns Ar name ]
+.Ss \eF Ns Bq Ar name
 Switch font family (groff extension); ignored by
 .Xr mandoc 1 .
 For short names, there are variants
 .No \eF Ns Ar c
 and
 .No \eF( Ns Ar cc .
-.Ss \ef[ Ns Ar name ]
+.Ss \ef Ns Bq Ar name
 Switch to the font
 .Ar name ,
 see
@@ -1946,7 +1959,7 @@ For short names, there are variants
 .No \ef Ns Ar c
 and
 .No \ef( Ns Ar cc .
-.Ss \eg[ Ns Ar name ]
+.Ss \eg Ns Bq Ar name
 Interpolate the format of a number register; ignored by
 .Xr mandoc 1 .
 For short names, there are variants
@@ -1956,11 +1969,14 @@ and
 .Ss \eH\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
 Set the height of the current font; ignored by
 .Xr mandoc 1 .
-.Ss \eh\(aq Ns Ar width Ns \(aq
-Horizontal motion relative to the current position.
+.Ss \eh\(aq Ns Oo Cm \&| Oc Ns Ar width Ns \(aq
+Horizontal motion.
+If the vertical bar is given, the motion is relative to the current
+indentation.
+Otherwise, it is relative to the current position.
 The default scaling unit is
 .Cm m .
-.Ss \ek[ Ns Ar name ]
+.Ss \ek Ns Bq Ar name
 Mark horizontal input place in register; ignored by
 .Xr mandoc 1 .
 For short names, there are variants
@@ -1975,14 +1991,14 @@ Draw a horizontal line of
 .Ar width
 using the glyph
 .Ar c .
-.Ss \eM[ Ns Ar name ]
+.Ss \eM Ns Bq Ar name
 Set fill (background) color (groff extension); ignored by
 .Xr mandoc 1 .
 For short names, there are variants
 .No \eM Ns Ar c
 and
 .No \eM( Ns Ar cc .
-.Ss \em[ Ns Ar name ]
+.Ss \em Ns Bq Ar name
 Set glyph drawing color (groff extension); ignored by
 .Xr mandoc 1 .
 For short names, there are variants
@@ -1993,13 +2009,19 @@ and
 Character
 .Ar number
 on the current font.
-.Ss \en[ Ns Ar name ]
+.Ss \en Ns Oo +|- Oc Ns Bq Ar name
 Interpolate the number register
 .Ar name .
 For short names, there are variants
 .No \en Ns Ar c
 and
 .No \en( Ns Ar cc .
+If the optional sign is specified,
+the register is first incremented or decremented by the
+.Ar stepsize
+that was specified in the relevant
+.Ic \&nr
+request, and the changed value is interpolated.
 .Ss \eo\(aq Ns Ar string Ns \(aq
 Overstrike, writing all the characters contained in the
 .Ar string
@@ -2020,9 +2042,9 @@ Change point size; ignored by
 Alternative forms
 .No \es Ns Oo +|- Oc Ns Ar n ,
 .No \es Ns Oo +|- Oc Ns \(aq Ns Ar number Ns \(aq ,
-.No \es Ns [ Oo +|- Oc Ns Ar number ] ,
+.No \es Ns Bq Oo +|- Oc Ns Ar number ,
 and
-.No \es Ns Oo +|- Oc Ns [ Ar number Ns ]
+.No \es Ns Oo +|- Oc Ns Bq Ar number
 are also parsed and ignored.
 .Ss \et
 Horizontal tab; ignored by
@@ -2030,7 +2052,7 @@ Horizontal tab; ignored by
 .Ss \eu
 Move up by half a line; ignored by
 .Xr mandoc 1 .
-.Ss \eV[ Ns Ar name ]
+.Ss \eV Ns Bq Ar name
 Interpolate an environment variable; ignored by
 .Xr mandoc 1 .
 For short names, there are variants
@@ -2057,7 +2079,7 @@ as device control function; ignored in nroff mode and 
 .Ss \ex\(aq Ns Ar number Ns \(aq
 Extra line space function; ignored by
 .Xr mandoc 1 .
-.Ss \eY[ Ns Ar name ]
+.Ss \eY Ns Bq Ar name
 Output a string as a device control function; ignored in nroff mode and by
 .Xr mandoc 1 .
 For short names, there are variants