===================================================================
RCS file: /cvs/mandoc/mandoc.1,v
retrieving revision 1.135
retrieving revision 1.159
diff -u -p -r1.135 -r1.159
--- mandoc/mandoc.1	2015/01/24 01:58:33	1.135
+++ mandoc/mandoc.1	2015/04/03 08:46:17	1.159
@@ -1,4 +1,4 @@
-.\"	$Id: mandoc.1,v 1.135 2015/01/24 01:58:33 schwarze Exp $
+.\"	$Id: mandoc.1,v 1.159 2015/04/03 08:46:17 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2012, 2014, 2015 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: January 24 2015 $
+.Dd $Mdocdate: April 3 2015 $
 .Dt MANDOC 1
 .Os
 .Sh NAME
@@ -23,15 +23,13 @@
 .Nd format and display UNIX manuals
 .Sh SYNOPSIS
 .Nm mandoc
-.Op Fl acfhklV
-.Sm off
-.Op Fl I Cm os Li = Ar name
-.Sm on
-.Op Fl K Ns Ar encoding
+.Op Fl acfhkl
+.Op Fl I Cm os Ns = Ns Ar name
+.Op Fl K Ar encoding
 .Op Fl m Ns Ar format
-.Op Fl O Ns Ar option
-.Op Fl T Ns Ar output
-.Op Fl W Ns Ar level
+.Op Fl O Ar option
+.Op Fl T Ar output
+.Op Fl W Ar level
 .Op Ar
 .Sh DESCRIPTION
 The
@@ -49,7 +47,7 @@ or
 text from stdin, implying
 .Fl m Ns Cm andoc ,
 and produces
-.Fl T Ns Cm locale
+.Fl T Cm locale
 output.
 .Pp
 The options are as follows:
@@ -77,9 +75,7 @@ This overrides any earlier
 and
 .Fl l
 options.
-.Sm off
-.It Fl I Cm os Li = Ar name
-.Sm on
+.It Fl I Cm os Ns = Ns Ar name
 Override the default operating system
 .Ar name
 for the
@@ -93,7 +89,7 @@ macro.
 Display only the SYNOPSIS lines.
 Implies
 .Fl c .
-.It Fl K Ns Ar encoding
+.It Fl K Ar encoding
 Specify the input encoding.
 The supported
 .Ar encoding
@@ -141,18 +137,16 @@ See
 for available formats.
 Defaults to
 .Fl m Ns Cm andoc .
-.It Fl O Ns Ar option
+.It Fl O Ar option
 Comma-separated output options.
-.It Fl T Ns Ar output
+.It Fl T Ar output
 Output format.
 See
 .Sx Output Formats
 for available formats.
 Defaults to
-.Fl T Ns Cm locale .
-.It Fl V
-Print version and exit.
-.It Fl W Ns Ar level
+.Fl T Cm locale .
+.It Fl W Ar level
 Specify the minimum message
 .Ar level
 to be reported on the standard error output and to affect the exit status.
@@ -176,7 +170,7 @@ and
 for details.
 .Pp
 The special option
-.Fl W Ns Cm stop
+.Fl W Cm stop
 tells
 .Nm
 to exit after parsing a file that causes warnings or errors of at least
@@ -187,7 +181,7 @@ If both a
 and
 .Cm stop
 are requested, they can be joined with a comma, for example
-.Fl W Ns Cm error , Ns Cm stop .
+.Fl W Cm error , Ns Cm stop .
 .It Ar file
 Read input from zero or more files.
 If unspecified, reads from stdin.
@@ -256,54 +250,54 @@ The
 utility accepts the following
 .Fl T
 arguments, which correspond to output modes:
-.Bl -tag -width "-Tlocale"
-.It Fl T Ns Cm ascii
+.Bl -tag -width "-T locale"
+.It Fl T Cm ascii
 Produce 7-bit ASCII output.
 See
 .Sx ASCII Output .
-.It Fl T Ns Cm html
+.It Fl T Cm html
 Produce HTML5, CSS1, and MathML output.
 See
 .Sx HTML Output .
-.It Fl T Ns Cm lint
+.It Fl T Cm lint
 Parse only: produce no output.
 Implies
-.Fl W Ns Cm warning .
-.It Fl T Ns Cm locale
+.Fl W Cm warning .
+.It Fl T Cm locale
 Encode output using the current locale.
 This is the default.
 See
 .Sx Locale Output .
-.It Fl T Ns Cm man
+.It Fl T Cm man
 Produce
 .Xr man 7
 format output.
 See
 .Sx Man Output .
-.It Fl T Ns Cm pdf
+.It Fl T Cm pdf
 Produce PDF output.
 See
 .Sx PDF Output .
-.It Fl T Ns Cm ps
+.It Fl T Cm ps
 Produce PostScript output.
 See
 .Sx PostScript Output .
-.It Fl T Ns Cm tree
+.It Fl T Cm tree
 Produce an indented parse tree.
-.It Fl T Ns Cm utf8
+.It Fl T Cm utf8
 Encode output in the UTF\-8 multi-byte format.
 See
 .Sx UTF\-8 Output .
-.It Fl T Ns Cm xhtml
+.It Fl T Cm xhtml
 This is a synonym for
-.Fl T Ns Cm html .
+.Fl T Cm html .
 .El
 .Pp
 If multiple input files are specified, these will be processed by the
 corresponding filter in-order.
 .Ss ASCII Output
 Output produced by
-.Fl T Ns Cm ascii
+.Fl T Cm ascii
 is rendered in standard 7-bit ASCII documented in
 .Xr ascii 7 .
 .Pp
@@ -321,9 +315,6 @@ Emboldened characters are rendered as
 The special characters documented in
 .Xr mandoc_char 7
 are rendered best-effort in an ASCII equivalent.
-If no equivalent is found,
-.Sq \&?
-is used instead.
 .Pp
 Output width is limited to 78 visible columns unless literal input lines
 exceed this limit.
@@ -344,11 +335,11 @@ for example overfull lines or ugly line breaks.
 .It Cm width Ns = Ns Ar width
 The output width is set to
 .Ar width ,
-which will normalise to \(>=60.
+which will normalise to \(>=58.
 .El
 .Ss HTML Output
 Output produced by
-.Fl T Ns Cm html
+.Fl T Cm html
 conforms to HTML5 using optional self-closing tags.
 Default styles use only CSS1.
 Equations rendered from
@@ -359,8 +350,8 @@ The
 .Pa example.style.css
 file documents style-sheet classes available for customising output.
 If a style-sheet is not specified with
-.Fl O Ns Ar style ,
-.Fl T Ns Cm html
+.Fl O Cm style ,
+.Fl T Cm html
 defaults to simple output (via an embedded style-sheet)
 readable in any graphical or text-based web
 browser.
@@ -416,13 +407,13 @@ relative URI.
 .El
 .Ss Locale Output
 Locale-depending output encoding is triggered with
-.Fl T Ns Cm locale .
+.Fl T Cm locale .
 This is the default.
 .Pp
 This option is not available on all systems: systems without locale
 support, or those whose internal representation is not natively UCS-4,
 will fall back to
-.Fl T Ns Cm ascii .
+.Fl T Cm ascii .
 See
 .Sx ASCII Output
 for font style specification and available command-line arguments.
@@ -452,7 +443,7 @@ level controls which
 are displayed before copying the input to the output.
 .Ss PDF Output
 PDF-1.1 output may be generated by
-.Fl T Ns Cm pdf .
+.Fl T Cm pdf .
 See
 .Sx PostScript Output
 for
@@ -462,7 +453,7 @@ arguments and defaults.
 PostScript
 .Qq Adobe-3.0
 Level-2 pages may be generated by
-.Fl T Ns Cm ps .
+.Fl T Cm ps .
 Output pages default to letter sized and are rendered in the Times font
 family, 11-point.
 Margins are calculated as 1/9 the page length and width.
@@ -494,7 +485,7 @@ is used.
 .El
 .Ss UTF\-8 Output
 Use
-.Fl T Ns Cm utf8
+.Fl T Cm utf8
 to force a UTF\-8 locale.
 See
 .Sx Locale Output
@@ -511,7 +502,8 @@ Specifies the pagination program to use when
 .Ev MANPAGER
 is not defined.
 If neither PAGER nor MANPAGER is defined,
-.Pa /usr/bin/more Fl s
+.Xr more 1
+.Fl s
 will be used.
 .El
 .Sh EXIT STATUS
@@ -530,21 +522,21 @@ they were lower than the requested
 .Ar level .
 .It 2
 At least one warning occurred, but no error, and
-.Fl W Ns Cm warning
+.Fl W Cm warning
 was specified.
 .It 3
 At least one parsing error occurred,
 but no unsupported feature was encountered, and
-.Fl W Ns Cm error
+.Fl W Cm error
 or
-.Fl W Ns Cm warning
+.Fl W Cm warning
 was specified.
 .It 4
 At least one unsupported feature was encountered, and
-.Fl W Ns Cm unsupp ,
-.Fl W Ns Cm error
+.Fl W Cm unsupp ,
+.Fl W Cm error
 or
-.Fl W Ns Cm warning
+.Fl W Cm warning
 was specified.
 .It 5
 Invalid command line arguments were specified.
@@ -558,28 +550,28 @@ to exit at once, possibly in the middle of parsing or 
 .El
 .Pp
 Note that selecting
-.Fl T Ns Cm lint
+.Fl T Cm lint
 output mode implies
-.Fl W Ns Cm warning .
+.Fl W Cm warning .
 .Sh EXAMPLES
 To page manuals to the terminal:
 .Pp
-.Dl $ mandoc \-Wall,stop mandoc.1 2\*(Gt&1 | less
+.Dl $ mandoc \-W all,stop mandoc.1 2\*(Gt&1 | less
 .Dl $ mandoc mandoc.1 mdoc.3 mdoc.7 | less
 .Pp
 To produce HTML manuals with
 .Ar style.css
 as the style-sheet:
 .Pp
-.Dl $ mandoc \-Thtml -Ostyle=style.css mdoc.7 \*(Gt mdoc.7.html
+.Dl $ mandoc \-T html -O style=style.css mdoc.7 \*(Gt mdoc.7.html
 .Pp
 To check over a large set of manuals:
 .Pp
-.Dl $ mandoc \-Tlint `find /usr/src -name \e*\e.[1-9]`
+.Dl $ mandoc \-T lint \(gafind /usr/src -name \e*\e.[1-9]\(ga
 .Pp
 To produce a series of PostScript manuals for A4 paper:
 .Pp
-.Dl $ mandoc \-Tps \-Opaper=a4 mdoc.7 man.7 \*(Gt manuals.ps
+.Dl $ mandoc \-T ps \-O paper=a4 mdoc.7 man.7 \*(Gt manuals.ps
 .Pp
 Convert a modern
 .Xr mdoc 7
@@ -589,7 +581,7 @@ format, for use on systems lacking an
 .Xr mdoc 7
 parser:
 .Pp
-.Dl $ mandoc \-Tman foo.mdoc \*(Gt foo.man
+.Dl $ mandoc \-T man foo.mdoc \*(Gt foo.man
 .Sh DIAGNOSTICS
 Messages displayed by
 .Nm
@@ -656,7 +648,7 @@ levels except those about non-existent or unreadable i
 are hidden unless their level, or a lower level, is requested using a
 .Fl W
 option or
-.Fl T Ns Cm lint
+.Fl T Cm lint
 output mode.
 .Ss Warnings related to the document prologue
 .Bl -ohang
@@ -732,9 +724,9 @@ macro occurs after some non-prologue macro, but still 
 .Pq mdoc
 The
 .Ic \&Dt
-macro can only occur before the first non-prologue macro
-because traditional formatters write the page header
-before parsing the document body.
+macro appears after the first non-prologue macro.
+Traditional formatters cannot handle this because
+they write the page header before parsing the document body.
 Even though this technical restriction does not apply to
 .Nm ,
 traditional semantics is preserved.
@@ -776,17 +768,33 @@ This may confuse
 .Xr makewhatis 8
 and
 .Xr apropos 1 .
-.It Sy "bad NAME section contents"
+.It Sy "NAME section without name"
 .Pq mdoc
-The last node in the NAME section is not an
+The NAME section does not contain any
+.Ic \&Nm
+child macro.
+.It Sy "NAME section without description"
+.Pq mdoc
+The NAME section lacks the mandatory
 .Ic \&Nd
-macro, or any preceding macro is not
-.Ic \&Nm ,
-or the NAME section is completely empty.
-This may confuse
-.Xr makewhatis 8
+child macro.
+.It Sy "description not at the end of NAME"
+.Pq mdoc
+The NAME section does contain an
+.Ic \&Nd
+child macro, but other content follows it.
+.It Sy "bad NAME section content"
+.Pq mdoc
+The NAME section contains plain text or macros other than
+.Ic \&Nm
 and
-.Xr apropos 1 .
+.Ic \&Nd .
+.It Sy "missing description line, using \(dq\(dq"
+.Pq mdoc
+The
+.Ic \&Nd
+macro lacks the required argument.
+The title line of the manual will end after the dash.
 .It Sy "sections out of conventional order"
 .Pq mdoc
 A standard section occurs after another section it usually precedes.
@@ -806,7 +814,7 @@ In the SEE ALSO section, an
 macro with a lower section number follows one with a higher number,
 or two
 .Ic \&Xr
-macros refering to the same section are out of alphabetical order.
+macros referring to the same section are out of alphabetical order.
 .It Sy "unusual Xr punctuation"
 .Pq mdoc
 In the SEE ALSO section, punctuation between two
@@ -833,7 +841,7 @@ manual for replacements.
 .Pq mdoc
 The name of a macro that is not callable appears on a macro line.
 It is printed verbatim.
-If the intention is to call it, move it to its own line;
+If the intention is to call it, move it to its own input line;
 otherwise, escape it by prepending
 .Sq \e& .
 .It Sy "skipping paragraph macro"
@@ -992,6 +1000,18 @@ clause.
 .It Sy "skipping empty macro"
 .Pq mdoc
 The indicated macro has no arguments and hence no effect.
+.It Sy "empty block"
+.Pq mdoc , man
+A
+.Ic \&Bd ,
+.Ic \&Bk ,
+.Ic \&Bl ,
+.Ic \&D1 ,
+.Ic \&Dl ,
+.Ic \&RS ,
+or
+.Ic \&UR
+block contains nothing in its body and will produce no output.
 .It Sy "empty argument, using 0n"
 .Pq mdoc
 The required width is missing after
@@ -1001,12 +1021,6 @@ or
 .Fl offset
 or
 .Fl width.
-.It Sy "argument count wrong"
-.Pq mdoc , man
-The indicated macro has too few or too many arguments.
-The syntax tree will contain the wrong number of arguments as given.
-Formatting behaviour depends on the specific macro in question.
-Note that the same message may also occur as an ERROR, see below.
 .It Sy "missing display type, using -ragged"
 .Pq mdoc
 The
@@ -1038,6 +1052,12 @@ The
 macro is called without an argument before
 .Ic \&Nm
 has first been called with an argument.
+.It Sy "missing function name, using \(dq\(dq"
+.Pq mdoc
+The
+.Ic \&Fo
+macro is called without an argument.
+No function name is printed.
 .It Sy "empty head in list item"
 .Pq mdoc
 In a
@@ -1065,21 +1085,18 @@ list, an
 .Ic \&It
 block is empty.
 An empty list item is shown.
-.It Sy "missing font type"
+.It Sy "missing font type, using \efR"
 .Pq mdoc
 A
 .Ic \&Bf
 macro has no argument.
-It switches to the default font,
-.Cm \efR .
-.It Sy "unknown font type"
+It switches to the default font.
+.It Sy "unknown font type, using \efR"
 .Pq mdoc
 The
 .Ic \&Bf
 argument is invalid.
-The default font
-.Cm \efR
-is used instead.
+The default font is used instead.
 .It Sy "nothing follows prefix"
 .Pq mdoc
 A
@@ -1088,6 +1105,14 @@ macro has no argument, or only one argument and no mac
 on the same input line.
 This defeats its purpose; in particular, spacing is not suppressed
 before the text or macros following on the next input line.
+.It Sy "empty reference block"
+.Pq mdoc
+An
+.Ic \&Rs
+macro is immediately followed by an
+.Ic \&Re
+macro on the next input line.
+Such an empty block does not produce any output.
 .It Sy "missing -std argument, adding it"
 .Pq mdoc
 An
@@ -1102,6 +1127,18 @@ The
 utility assumes
 .Fl std
 even when it is not specified, but other implementations may not.
+.It Sy "missing option string, using \(dq\(dq"
+.Pq man
+The
+.Ic \&OP
+macro is invoked without any argument.
+An empty pair of square brackets is shown.
+.It Sy "missing resource identifier, using \(dq\(dq"
+.Pq man
+The
+.Ic \&UR
+macro is invoked without any argument.
+An empty pair of angle brackets is shown.
 .It Sy "missing eqn box, using \(dq\(dq"
 .Pq eqn
 A diacritic mark or a binary operator is found,
@@ -1166,6 +1203,15 @@ list has a
 .Fl width
 argument.
 That has no effect.
+.It Sy "wrong number of cells"
+In a line of a
+.Ic \&Bl Fl column
+list, the number of tabs or
+.Ic \&Ta
+macros is less than the number expected from the list header line
+or exceeds the expected number by more than one.
+Missing cells remain empty, and all cells exceeding the number of
+columns are joined into one single cell.
 .It Sy "unknown AT&T UNIX version"
 .Pq mdoc
 An
@@ -1217,6 +1263,12 @@ request or a
 layout modifier has an unknown
 .Ar font
 argument.
+.It Sy "odd number of characters in request"
+.Pq roff
+A
+.Ic \&tr
+request contains an odd number of characters.
+The last character is mapped to the blank character.
 .El
 .Ss "Warnings related to plain text"
 .Bl -ohang
@@ -1273,20 +1325,86 @@ its value is implicitly set to the empty string.
 However, defining strings explicitly before use
 keeps the code more readable.
 .El
-.Ss "Errors related to equations"
-.Bl -inset -compact
-.It "unexpected equation scope closure"
-.It "equation scope open on exit"
-.It "overlapping equation scopes"
-.It "unexpected end of equation"
+.Ss "Warnings related to tables"
+.Bl -ohang
+.It Sy "tbl line starts with span"
+.Pq tbl
+The first cell in a table layout line is a horizontal span
+.Pq Sq Cm s .
+Data provided for this cell is ignored, and nothing is printed in the cell.
+.It Sy "tbl column starts with span"
+.Pq tbl
+The first line of a table layout specification
+requests a vertical span
+.Pq Sq Cm ^ .
+Data provided for this cell is ignored, and nothing is printed in the cell.
+.It Sy "skipping vertical bar in tbl layout"
+.Pq tbl
+A table layout specification contains more than two consecutive vertical bars.
+A double bar is printed, all additional bars are discarded.
 .El
 .Ss "Errors related to tables"
-.Bl -inset -compact
-.It "no table layout cells specified"
-.It "no table data cells specified"
-.It "ignore data in cell"
-.It "data block still open"
-.It "ignoring extra data cells"
+.Bl -ohang
+.It Sy "non-alphabetic character in tbl options"
+.Pq tbl
+The table options line contains a character other than a letter,
+blank, or comma where the beginning of an option name is expected.
+The character is ignored.
+.It Sy "skipping unknown tbl option"
+.Pq tbl
+The table options line contains a string of letters that does not
+match any known option name.
+The word is ignored.
+.It Sy "missing tbl option argument"
+.Pq tbl
+A table option that requires an argument is not followed by an
+opening parenthesis, or the opening parenthesis is immediately
+followed by a closing parenthesis.
+The option is ignored.
+.It Sy "wrong tbl option argument size"
+.Pq tbl
+A table option argument contains an invalid number of characters.
+Both the option and the argument are ignored.
+.It Sy "empty tbl layout"
+.Pq tbl
+A table layout specification is completely empty,
+specifying zero lines and zero columns.
+As a fallback, a single left-justified column is used.
+.It Sy "invalid character in tbl layout"
+.Pq tbl
+A table layout specification contains a character that can neither
+be interpreted as a layout key character nor as a layout modifier,
+or a modifier precedes the first key.
+The invalid character is discarded.
+.It Sy "unmatched parenthesis in tbl layout"
+.Pq tbl
+A table layout specification contains an opening parenthesis,
+but no matching closing parenthesis.
+The rest of the input line, starting from the parenthesis, has no effect.
+.It Sy "tbl without any data cells"
+.Pq tbl
+A table does not contain any data cells.
+It will probably produce no output.
+.It Sy "ignoring data in spanned tbl cell"
+.Pq tbl
+A table cell is marked as a horizontal span
+.Pq Sq Cm s
+or vertical span
+.Pq Sq Cm ^
+in the table layout, but it contains data.
+The data is ignored.
+.It Sy "ignoring extra tbl data cells"
+.Pq tbl
+A data line contains more cells than the corresponding layout line.
+The data in the extra cells is ignored.
+.It Sy "data block open at end of tbl"
+.Pq tbl
+A data block is opened with
+.Cm T{ ,
+but never closed with a matching
+.Cm T} .
+The remaining data lines of the table are all put into one cell,
+and any remaining cells stay empty.
 .El
 .Ss "Errors related to roff, mdoc, and man code"
 .Bl -ohang
@@ -1387,7 +1505,7 @@ macros as well as tables require explicit closing by d
 A block that doesn't support bad nesting
 ends before all of its children are properly closed.
 The open child nodes are closed implicitly.
-.It Sy "scope open on exit"
+.It Sy "appending missing end of block"
 .Pq mdoc , man , eqn , tbl , roff
 At the end of the document, an explicit
 .Xr mdoc 7
@@ -1437,12 +1555,6 @@ When parsing for a request or a user-defined macro nam
 only the escape sequence is discarded.
 The characters preceding it are used as the request or macro name,
 the characters following it are used as the arguments to the request or macro.
-.It Sy "argument count wrong"
-.Pq mdoc , man , roff
-The indicated request or macro has too few or too many arguments.
-The syntax tree will contain the wrong number of arguments as given.
-Formatting behaviour depends on the specific request or macro in question.
-Note that the same message may also occur as a WARNING, see above.
 .It Sy "NOT IMPLEMENTED: Bd -file"
 .Pq mdoc
 For security reasons, the
@@ -1525,7 +1637,10 @@ An
 .Ic \&Ef ,
 .Ic \&Ek ,
 .Ic \&El ,
+.Ic \&Lp ,
+.Ic \&Pp ,
 .Ic \&Re ,
+.Ic \&Rs ,
 or
 .Ic \&Ud
 macro, an
@@ -1543,19 +1658,54 @@ or
 .Ic \&EN
 macro, or a
 .Xr roff 7
+.Ic \&br ,
+.Ic \&fi ,
+or
+.Ic \&nf
+request or
 .Sq \&..
 block closing request is invoked with at least one argument.
 All arguments are ignored.
 .It Sy "skipping excess arguments"
 .Pq mdoc , man , roff
-The
-.Ic \&Bf
-macro is invoked with more than one argument, the
+A macro or request is invoked with too many arguments:
+.Bl -dash -offset 2n -width 2n -compact
+.It
+.Ic \&Fo ,
+.Ic \&PD ,
+.Ic \&RS ,
+.Ic \&UR ,
+.Ic \&ft ,
+or
+.Ic \&sp
+with more than one argument
+.It
+.Ic \&An
+with another argument after
+.Fl split
+or
+.Fl nosplit
+.It
 .Ic \&RE
-macro is invoked with more than one argument
-or with a non-integer argument, or a request of the
+with more than one argument or with a non-integer argument
+.It
+.Ic \&OP
+or a request of the
 .Ic \&de
-family is invoked with more than two arguments.
+family with more than two arguments
+.It
+.Ic \&Dt
+with more than three arguments
+.It
+.Ic \&TH
+with more than five arguments
+.It
+.Ic \&Bd ,
+.Ic \&Bk ,
+or
+.Ic \&Bl
+with invalid arguments
+.El
 The excess arguments are ignored.
 .El
 .Ss Unsupported features
@@ -1568,6 +1718,14 @@ cannot handle input files larger than its arbitrary si
 of 2^31 bytes (2 Gigabytes).
 Since useful manuals are always small, this is not a problem in practice.
 Parsing is aborted as soon as the condition is detected.
+.It Sy "unsupported control character"
+.Pq roff
+An ASCII control character supported by other
+.Xr roff 7
+implementations but not by
+.Nm
+was found in an input file.
+It is replaced by a question mark.
 .It Sy "unsupported roff request"
 .Pq roff
 An input file contains a
@@ -1576,93 +1734,29 @@ request supported by GNU troff or Heirloom troff but n
 .Nm ,
 and it is likely that this will cause information loss
 or considerable misformatting.
-.It Sy "bad table syntax"
-.It Sy "bad table option"
-.It Sy "bad table layout"
+.It Sy "eqn delim option in tbl"
+.Pq eqn , tbl
+The options line of a table defines equation delimiters.
+Any equation source code contained in the table will be printed unformatted.
+.It Sy "unsupported table layout modifier"
+.Pq tbl
+A table layout specification contains an
+.Sq Cm m
+modifier.
+The modifier is discarded.
 .It Sy "ignoring macro in table"
-.El
-.Sh COMPATIBILITY
-This section summarises
-.Nm
-compatibility with GNU troff.
-Each input and output format is separately noted.
-.Ss ASCII Compatibility
-.Bl -bullet -compact
-.It
-Unrenderable unicode codepoints specified with
-.Sq \e[uNNNN]
-escapes are printed as
-.Sq \&?
-in mandoc.
-In GNU troff, these raise an error.
-.It
-The
-.Sq \&Bd \-literal
-and
-.Sq \&Bd \-unfilled
-macros of
+.Pq tbl , mdoc , man
+A table contains an invocation of an
 .Xr mdoc 7
-in
-.Fl T Ns Cm ascii
-are synonyms, as are \-filled and \-ragged.
-.It
-In historic GNU troff, the
-.Sq \&Pa
-.Xr mdoc 7
-macro does not underline when scoped under an
-.Sq \&It
-in the FILES section.
-This behaves correctly in
-.Nm .
-.It
-A list or display following the
-.Sq \&Ss
-.Xr mdoc 7
-macro in
-.Fl T Ns Cm ascii
-does not assert a prior vertical break, just as it doesn't with
-.Sq \&Sh .
-.It
-The
-.Sq \&na
+or
 .Xr man 7
-macro in
-.Fl T Ns Cm ascii
-has no effect.
-.It
-Words aren't hyphenated.
+macro or of an undefined macro.
+The macro is ignored, and its arguments are handled
+as if they were a text line.
 .El
-.Ss HTML Compatibility
-.Bl -bullet -compact
-.It
-The
-.Sq \efP
-escape will revert the font to the previous
-.Sq \ef
-escape, not to the last rendered decoration, which is now dictated by
-CSS instead of hard-coded.
-It also will not span past the current scope,
-for the same reason.
-Note that in
-.Sx ASCII Output
-mode, this will work fine.
-.It
-The
-.Xr mdoc 7
-.Sq \&Bl \-hang
-and
-.Sq \&Bl \-tag
-list types render similarly (no break following overreached left-hand
-side) due to the expressive constraints of HTML.
-.It
-The
-.Xr man 7
-.Sq IP
-and
-.Sq TP
-lists render similarly.
-.El
 .Sh SEE ALSO
+.Xr apropos 1 ,
+.Xr man 1 ,
 .Xr eqn 7 ,
 .Xr man 7 ,
 .Xr mandoc_char 7 ,
@@ -1670,35 +1764,19 @@ lists render similarly.
 .Xr roff 7 ,
 .Xr tbl 7
 .Sh AUTHORS
+.An -nosplit
 The
 .Nm
 utility was written by
-.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
-.Sh CAVEATS
+.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
+and is maintained by
+.An Ingo Schwarze Aq Mt schwarze@openbsd.org .
+.Sh BUGS
 In
-.Fl T Ns Cm html
-and
-.Fl T Ns Cm xhtml ,
+.Fl T Cm html ,
 the maximum size of an element attribute is determined by
 .Dv BUFSIZ ,
 which is usually 1024 bytes.
 Be aware of this when setting long link
 formats such as
-.Fl O Ns Cm style Ns = Ns Ar really/long/link .
-.Pp
-Nesting elements within next-line element scopes of
-.Fl m Ns Cm an ,
-such as
-.Sq br
-within an empty
-.Sq B ,
-will confuse
-.Fl T Ns Cm html
-and
-.Fl T Ns Cm xhtml
-and cause them to forget the formatting of the prior next-line scope.
-.Pp
-The
-.Sq \(aq
-control character is an alias for the standard macro control character
-and does not emit a line-break as stipulated in GNU troff.
+.Fl O Cm style Ns = Ns Ar really/long/link .