Below DIAGNOSTICS, document the SYSERR message level;

[mandoc.git] / mandoc.1

diff --git a/mandoc.1 b/mandoc.1
index 3d1dc3cd245f698d1a857280e4544330f225ab00..745dd504ed61e08fac1d746076dd3faecdb3a79c 100644 (file)
--- a/mandoc.1
+++ b/mandoc.1
@@ -1,6 +1,7 @@
-.\"    $Id: mandoc.1,v 1.19 2009/06/15 09:35:16 kristaps Exp $
+.\"    $Id: mandoc.1,v 1.105 2014/06/23 22:03:30 schwarze Exp $

 .\"
 .\"

-.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
+.\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2012, 2014 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
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above


@@ -14,121 +15,113 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
 .\" 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 15 2009 $
+.Dd $Mdocdate: June 23 2014 $

 .Dt MANDOC 1
 .Os
 .Dt MANDOC 1
 .Os

-.\" SECTION

 .Sh NAME
 .Nm mandoc
 .Nd format and display UNIX manuals
 .Sh NAME
 .Nm mandoc
 .Nd format and display UNIX manuals

-.\" SECTION

 .Sh SYNOPSIS
 .Nm mandoc
 .Op Fl V
 .Sh SYNOPSIS
 .Nm mandoc
 .Op Fl V

-.Op Fl f Ns Ar option...
+.Sm off
+.Op Fl I Cm os Li = Ar name
+.Sm on

 .Op Fl m Ns Ar format
 .Op Fl m Ns Ar format

-.Op Fl W Ns Ar err...
+.Op Fl O Ns Ar option

 .Op Fl T Ns Ar output
 .Op Fl T Ns Ar output

-.Op Ar infile...
-.\" SECTION
+.Op Fl W Ns Ar level
+.Op Ar

 .Sh DESCRIPTION
 The
 .Nm
 .Sh DESCRIPTION
 The
 .Nm

-utility formats 
+utility formats

 .Ux
 .Ux

-manual pages for display.  The arguments are as follows:
+manual pages for display.
+.Pp
+By default,
+.Nm
+reads
+.Xr mdoc 7
+or
+.Xr man 7
+text from stdin, implying
+.Fl m Ns Cm andoc ,
+and produces
+.Fl T Ns Cm ascii
+output.
+.Pp
+The arguments are as follows:

 .Bl -tag -width Ds
 .Bl -tag -width Ds

-.\" ITEM
-.It Fl f Ns Ar option...
-Override default compiler behaviour.  See 
-.Sx Compiler Options
-for details.
-.\" ITEM
+.Sm off
+.It Fl I Cm os Li = Ar name
+.Sm on
+Override the default operating system
+.Ar name
+for the
+.Xr mdoc 7
+.Sq \&Os
+macro.

 .It Fl m Ns Ar format
 .It Fl m Ns Ar format

-Input format.  See
+Input format.
+See

 .Sx Input Formats
 .Sx Input Formats

-for available formats.  Defaults to
-.Fl m Ns Ar andoc .
-.\" ITEM
+for available formats.
+Defaults to
+.Fl m Ns Cm andoc .
+.It Fl O Ns Ar option
+Comma-separated output options.

 .It Fl T Ns Ar output
 .It Fl T Ns Ar output

-Output format.  See
+Output format.
+See

 .Sx Output Formats
 .Sx Output Formats

-for available formats.  Defaults to
-.Fl T Ns Ar ascii .
-.\" ITEM
+for available formats.
+Defaults to
+.Fl T Ns Cm ascii .

 .It Fl V
 Print version and exit.
 .It Fl V
 Print version and exit.

-.\" ITEM
-.It Fl W Ns Ar err...
-Print warning messages.  May be set to 
-.Fl W Ns Ar all
-for all warnings, 
-.Ar compat
-for groff/troff-compatibility warnings, or
-.Ar syntax
-for syntax warnings.  If
-.Fl W Ns Ar error 
-is specified, warnings are considered errors and cause utility
-termination.  Multiple 
-.Fl W
-arguments may be comma-separated, such as
-.Fl W Ns Ar error,all .
-.\" ITEM
-.It Ar infile...
-Read input from zero or more
-.Ar infile .
-If unspecified, reads from stdin.  If multiple files are specified,
-.Nm
-will halt with the first failed parse.
-.El
-.\" PARAGRAPH
-.Pp
-By default, 
-.Nm 
-reads 
-.Xr mdoc 7
+.It Fl W Ns Ar level
+Specify the minimum message
+.Ar level
+to be reported on the standard error output and to affect the exit status.
+The
+.Ar level
+can be
+.Cm warning ,
+.Cm error ,

 or
 or

-.Xr man 7
-text from stdin, implying
-.Fl m Ns Ar andoc ,
-and prints 78-column backspace-encoded output to stdout as if
-.Fl T Ns Ar ascii
-were provided.
-.\" PARAGRAPH
-.Pp
-.Ex -std mandoc
-.\" SUB-SECTION
-.Ss Punctuation
-If punctuation is set apart from words, such as in the phrase
-.Dq to be \&, or not to be ,
-it's processed by
-.Nm
-according to the following rules.  Opening punctuation
-.Po
-.Sq \&( , 
-.Sq \&[ , 
-and
-.Sq \&{
-.Pc 
-is not followed by a space. Closing punctuation
-.Po
-.Sq \&. , 
-.Sq \&, , 
-.Sq \&; , 
-.Sq \&: , 
-.Sq \&? , 
-.Sq \&! , 
-.Sq \&) , 
-.Sq \&] 
+.Cm fatal .
+The default is
+.Fl W Ns Cm fatal ;
+.Fl W Ns Cm all
+is an alias for
+.Fl W Ns Cm warning .
+See
+.Sx EXIT STATUS

 and
 and

-.Sq \&}
-.Pc 
-is not preceded by whitespace.
+.Sx DIAGNOSTICS
+for details.

 .Pp
 .Pp

-If the input is
-.Xr mdoc 7 ,
-these rules are also applied to macro arguments when appropriate.
-.\" SUB-SECTION
+The special option
+.Fl W Ns Cm stop
+tells
+.Nm
+to exit after parsing a file that causes warnings or errors of at least
+the requested level.
+No formatted output will be produced from that file.
+If both a
+.Ar level
+and
+.Cm stop
+are requested, they can be joined with a comma, for example
+.Fl W Ns Cm error , Ns Cm stop .
+.It Ar file
+Read input from zero or more files.
+If unspecified, reads from stdin.
+If multiple files are specified,
+.Nm
+will halt with the first failed parse.
+.El

 .Ss Input Formats
 The
 .Nm
 .Ss Input Formats
 The
 .Nm


@@ -137,153 +130,558 @@ utility accepts
 and
 .Xr man 7
 input with
 and
 .Xr man 7
 input with

-.Fl m Ns Ar doc
+.Fl m Ns Cm doc

 and
 and

-.Fl m Ns Ar an ,
-respectively.  The
+.Fl m Ns Cm an ,
+respectively.
+The

 .Xr mdoc 7
 format is
 .Em strongly
 .Xr mdoc 7
 format is
 .Em strongly

-recommended; 
+recommended;

 .Xr man 7
 should only be used for legacy manuals.
 .Pp
 A third option,
 .Xr man 7
 should only be used for legacy manuals.
 .Pp
 A third option,

-.Fl m Ns Ar andoc ,
+.Fl m Ns Cm andoc ,

 which is also the default, determines encoding on-the-fly: if the first
 which is also the default, determines encoding on-the-fly: if the first

-non-comment macro is 
-.Sq \&.Dd
+non-comment macro is
+.Sq \&Dd

 or
 or

-.Sq \&.Dt ,
-the 
+.Sq \&Dt ,
+the

 .Xr mdoc 7
 parser is used; otherwise, the
 .Xr man 7
 parser is used.
 .Pp
 If multiple
 .Xr mdoc 7
 parser is used; otherwise, the
 .Xr man 7
 parser is used.
 .Pp
 If multiple

-files are specified with 
-.Fl m Ns Ar andoc , 
-each has its file-type determined this way.  If multiple files are
+files are specified with
+.Fl m Ns Cm andoc ,
+each has its file-type determined this way.
+If multiple files are

 specified and
 specified and

-.Fl m Ns Ar doc
+.Fl m Ns Cm doc

 or
 or

-.Fl m Ns Ar an
+.Fl m Ns Cm an

 is specified, then this format is used exclusively.
 is specified, then this format is used exclusively.

-.\" .Pp
-.\" The following escape sequences are recognised, although the per-format
-.\" compiler may not allow certain sequences.
-.\" .Bl -tag -width Ds -offset XXXX
-.\" .It \efX
-.\" sets the font mode to X (B, I, R or P, where P resets the font)
-.\" .It \eX, \e(XX, \e[XN]
-.\" queries the special-character table for a corresponding symbol
-.\" .It \e*X, \e*(XX, \e*[XN]
-.\" deprecated special-character format
-.\" .El
-.\" SUB-SECTION

 .Ss Output Formats
 The
 .Nm
 utility accepts the following
 .Fl T
 .Ss Output Formats
 The
 .Nm
 utility accepts the following
 .Fl T

-arguments:
-.Bl -tag -width Ds
-.It Fl T Ns Ar ascii
-Produce 7-bit ASCII output, backspace-encoded for bold and underline
-styles.  This is the default.
-.It Fl T Ns Ar tree
-Produce an indented parse tree.
-.It Fl T Ns Ar lint
+arguments, which correspond to output modes:
+.Bl -tag -width "-Tlocale"
+.It Fl T Ns Cm ascii
+Produce 7-bit ASCII output.
+This is the default.
+See
+.Sx ASCII Output .
+.It Fl T Ns Cm html
+Produce strict CSS1/HTML-4.01 output.
+See
+.Sx HTML Output .
+.It Fl T Ns Cm lint

 Parse only: produce no output.
 Parse only: produce no output.

+Implies
+.Fl W Ns Cm warning .
+.It Fl T Ns Cm locale
+Encode output using the current locale.
+See
+.Sx Locale Output .
+.It Fl T Ns Cm man
+Produce
+.Xr man 7
+format output.
+See
+.Sx Man Output .
+.It Fl T Ns Cm pdf
+Produce PDF output.
+See
+.Sx PDF Output .
+.It Fl T Ns Cm ps
+Produce PostScript output.
+See
+.Sx PostScript Output .
+.It Fl T Ns Cm tree
+Produce an indented parse tree.
+.It Fl T Ns Cm utf8
+Encode output in the UTF\-8 multi-byte format.
+See
+.Sx UTF\-8 Output .
+.It Fl T Ns Cm xhtml
+Produce strict CSS1/XHTML-1.0 output.
+See
+.Sx XHTML Output .

 .El
 .Pp
 If multiple input files are specified, these will be processed by the
 corresponding filter in-order.
 .El
 .Pp
 If multiple input files are specified, these will be processed by the
 corresponding filter in-order.

-.\" SUB-SECTION
-.Ss Compiler Options
-Default compiler behaviour may be overriden with the
-.Fl f
-flag.
+.Ss ASCII Output
+Output produced by
+.Fl T Ns Cm ascii ,
+which is the default, is rendered in standard 7-bit ASCII documented in
+.Xr ascii 7 .
+.Pp
+Font styles are applied by using back-spaced encoding such that an
+underlined character
+.Sq c
+is rendered as
+.Sq _ Ns \e[bs] Ns c ,
+where
+.Sq \e[bs]
+is the back-space character number 8.
+Emboldened characters are rendered as
+.Sq c Ns \e[bs] Ns c .
+.Pp
+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.
+.Pp
+The following
+.Fl O
+arguments are accepted:
+.Bl -tag -width Ds
+.It Cm indent Ns = Ns Ar indent
+The left margin for normal text is set to
+.Ar indent
+blank characters instead of the default of five for
+.Xr mdoc 7
+and seven for
+.Xr man 7 .
+Increasing this is not recommended; it may result in degraded formatting,
+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.
+.El
+.Ss HTML Output
+Output produced by
+.Fl T Ns Cm html
+conforms to HTML-4.01 strict.
+.Pp
+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
+defaults to simple output readable in any graphical or text-based web
+browser.
+.Pp
+Special characters are rendered in decimal-encoded UTF\-8.
+.Pp
+The following
+.Fl O
+arguments are accepted:

 .Bl -tag -width Ds
 .Bl -tag -width Ds

-.It Fl f Ns Ar ign-scope
-When rewinding the scope of a block macro, forces the compiler to ignore
-scope violations.  This can seriously mangle the resulting tree.
-.Pq mdoc only
-.It Fl f Ns Ar ign-escape
-Ignore invalid escape sequences.
-.It Fl f Ns Ar ign-macro
-Ignore unknown macros at the start of input lines (default for 
+.It Cm fragment
+Omit the
+.Aq !DOCTYPE
+declaration and the
+.Aq html ,
+.Aq head ,
+and
+.Aq body
+elements and only emit the subtree below the
+.Aq body
+element.
+The
+.Cm style
+argument will be ignored.
+This is useful when embedding manual content within existing documents.
+.It Cm includes Ns = Ns Ar fmt
+The string
+.Ar fmt ,
+for example,
+.Ar ../src/%I.html ,
+is used as a template for linked header files (usually via the
+.Sq \&In
+macro).
+Instances of
+.Sq \&%I
+are replaced with the include filename.
+The default is not to present a
+hyperlink.
+.It Cm man Ns = Ns Ar fmt
+The string
+.Ar fmt ,
+for example,
+.Ar ../html%S/%N.%S.html ,
+is used as a template for linked manuals (usually via the
+.Sq \&Xr
+macro).
+Instances of
+.Sq \&%N
+and
+.Sq %S
+are replaced with the linked manual's name and section, respectively.
+If no section is included, section 1 is assumed.
+The default is not to
+present a hyperlink.
+.It Cm style Ns = Ns Ar style.css
+The file
+.Ar style.css
+is used for an external style-sheet.
+This must be a valid absolute or
+relative URI.
+.El
+.Ss Locale Output
+Locale-depending output encoding is triggered with
+.Fl T Ns Cm locale .
+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 .
+See
+.Sx ASCII Output
+for font style specification and available command-line arguments.
+.Ss Man Output
+Translate input format into

 .Xr man 7
 .Xr man 7

-parsing).
-.It Fl f Ns Ar no-ign-macro
-Do not ignore unknown macros at the start of input lines (default for 
+output format.
+This is useful for distributing manual sources to legacy systems
+lacking

 .Xr mdoc 7
 .Xr mdoc 7

-parsing).
+formatters.
+.Pp
+If
+.Xr mdoc 7
+is passed as input, it is translated into
+.Xr man 7 .
+If the input format is
+.Xr man 7 ,
+the input is copied to the output, expanding any
+.Xr roff 7
+.Sq so
+requests.
+The parser is also run, and as usual, the
+.Fl W
+level controls which
+.Sx DIAGNOSTICS
+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 .
+See
+.Sx PostScript Output
+for
+.Fl O
+arguments and defaults.
+.Ss PostScript Output
+PostScript
+.Qq Adobe-3.0
+Level-2 pages may be generated by
+.Fl T Ns 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.
+Line-height is 1.4m.
+.Pp
+Special characters are rendered as in
+.Sx ASCII Output .
+.Pp
+The following
+.Fl O
+arguments are accepted:
+.Bl -tag -width Ds
+.It Cm paper Ns = Ns Ar name
+The paper size
+.Ar name
+may be one of
+.Ar a3 ,
+.Ar a4 ,
+.Ar a5 ,
+.Ar legal ,
+or
+.Ar letter .
+You may also manually specify dimensions as
+.Ar NNxNN ,
+width by height in millimetres.
+If an unknown value is encountered,
+.Ar letter
+is used.

 .El
 .El

-.\" PARAGRAPH
+.Ss UTF\-8 Output
+Use
+.Fl T Ns Cm utf8
+to force a UTF\-8 locale.
+See
+.Sx Locale Output
+for details and options.
+.Ss XHTML Output
+Output produced by
+.Fl T Ns Cm xhtml
+conforms to XHTML-1.0 strict.

 .Pp
 .Pp

-As with the
+See
+.Sx HTML Output
+for details; beyond generating XHTML tags instead of HTML tags, these
+output modes are identical.
+.Sh EXIT STATUS
+The
+.Nm
+utility exits with one of the following values, controlled by the message
+.Ar level
+associated with the

 .Fl W
 .Fl W

-flag, multiple
-.Fl f
-options may be grouped and delimited with a comma.  Using
-.Fl f Ns Ar ign-scope,ign-escape ,
-for example, will try to ignore scope and character-escape errors.
-.\" SECTION
+option:
+.Pp
+.Bl -tag -width Ds -compact
+.It 0
+No warnings or errors occurred, or those that did were ignored because
+they were lower than the requested
+.Ar level .
+.It 2
+At least one warning occurred, but no error, and
+.Fl W Ns Cm warning
+was specified.
+.It 3
+At least one parsing error occurred, but no fatal error, and
+.Fl W Ns Cm error
+or
+.Fl W Ns Cm warning
+was specified.
+.It 4
+A fatal parsing error occurred.
+.It 5
+Invalid command line arguments were specified.
+No input files have been read.
+.It 6
+An operating system error occurred, for example memory exhaustion or an
+error accessing input files.
+Such errors cause
+.Nm
+to exit at once, possibly in the middle of parsing or formatting a file.
+.El
+.Pp
+Note that selecting
+.Fl T Ns Cm lint
+output mode implies
+.Fl W Ns Cm warning .

 .Sh EXAMPLES
 To page manuals to the terminal:
 .Sh EXAMPLES
 To page manuals to the terminal:

-.\" PARAGRAPH

 .Pp
 .Pp

-.D1 % mandoc \-Wall,error mandoc.1 2>&1 | less
+.Dl $ mandoc \-Wall,stop mandoc.1 2\*(Gt&1 | less
+.Dl $ mandoc mandoc.1 mdoc.3 mdoc.7 | less

 .Pp
 .Pp

-.D1 % mandoc mandoc.1 mdoc.3 mdoc.7 | less
-.\" SECTION
-.Sh SEE ALSO
-.Xr mandoc_char 7 ,
-.Xr mdoc 7 ,
+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
+.Pp
+To check over a large set of manuals:
+.Pp
+.Dl $ mandoc \-Tlint `find /usr/src -name \e*\e.[1-9]`
+.Pp
+To produce a series of PostScript manuals for A4 paper:
+.Pp
+.Dl $ mandoc \-Tps \-Opaper=a4 mdoc.7 man.7 \*(Gt manuals.ps
+.Pp
+Convert a modern
+.Xr mdoc 7
+manual to the older

 .Xr man 7
 .Xr man 7

-.\" 
-.Sh AUTHORS
-The
-.Nm
-utility was written by 
-.An Kristaps Dzonsons Aq kristaps@kth.se .
-.\" SECTION
-.Sh CAVEATS
-The 
-.Nm
-utility in
-.Fl T Ns Ar ascii
-mode doesn't yet know how to display the following:
+format, for use on systems lacking an
+.Xr mdoc 7
+parser:

 .Pp
 .Pp

-.Bl -bullet -compact
-.It
-The \-hang 
-.Sq \&.Bl
-list is not yet supported.
+.Dl $ mandoc \-Tman foo.mdoc \*(Gt foo.man
+.Sh DIAGNOSTICS
+Standard error messages reporting parsing errors are prefixed by
+.Pp
+.D1 Nm Ns : Ar file : Ns Ar line : Ns Ar column : level :
+.Pp
+where the fields have the following meanings:
+.Bl -tag -width "column"
+.It Ar file
+The name of the input file causing the message.
+.It Ar line
+The line number in that input file.
+Line numbering starts at 1.
+.It Ar column
+The column number in that input file.
+Column numbering starts at 1.
+If the issue is caused by a word, the column number usually
+points to the first character of the word.
+.It Ar level
+The message level, printed in capital letters.

 .El
 .Pp
 .El
 .Pp

-Other macros still aren't supported by virtue of nobody complaining
-about their absence.  Please report any omissions: this is a work in
-progress.
+The
+.Ar line
+and
+.Ar column
+fields are omitted when meaningless.
+.Pp
+Message levels have the following meanings:
+.Bl -tag -width "warning"
+.It Cm syserr
+Opening or reading an input file failed, so the parser cannot
+even be started and no output is produced from that input file.
+.It Cm fatal
+The parser is unable to parse a given input file at all.
+No formatted output is produced from that input file.
+.It Cm error
+An input file contains syntax that cannot be safely interpreted,
+either because it is invalid or because
+.Nm
+does not implement it yet.
+By discarding part of the input or inserting missing tokens,
+the parser is able to continue, and the error does not prevent
+generation of formatted output, but typically, preparing that
+output involves information loss, broken document structure
+or unintended formatting.
+.It Cm warning
+An input file uses obsolete, discouraged or non-portable syntax.
+All the same, the meaning of the input is unambiguous and a correct
+rendering can be produced.
+Documents causing warnings may render poorly when using other
+formatting tools instead of
+.Nm .
+.El

 .Pp
 .Pp

-The following list documents differences between traditional
-.Xr nroff 1
-output and
-.Nm :
+Messages of the
+.Cm warning
+and
+.Cm error
+levels are hidden unless their level, or a lower level, is requested using a
+.Fl W
+option or
+.Fl T Ns Cm lint
+output mode.

 .Pp
 .Pp

+The
+.Nm
+utility may also print messages related to invalid command line arguments
+or operating system errors, for example when memory is exhausted.
+Such messages may not carry the prefix described above.
+.Sh COMPATIBILITY
+This section summarises
+.Nm
+compatibility with GNU troff.
+Each input and output format is separately noted.
+.Ss ASCII Compatibility

 .Bl -bullet -compact
 .Bl -bullet -compact

-.It 
-A list of display following
-.Sq \&.Ss
+.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
+.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
 does not assert a prior vertical break, just as it doesn't with

-.Sq \&.Sh .
+.Sq \&Sh .

 .It
 .It

-Special characters don't follow the current font style.
-.\" LIST-ITEM
+The
+.Sq \&na
+.Xr man 7
+macro in
+.Fl T Ns Cm ascii
+has no effect.

 .It
 .It

-The \-literal and \-unfilled 
-.Sq \&.Bd
-displays types are synonyms, as are \-filled and \-ragged.
+Words aren't hyphenated.

 .El
 .El

+.Ss HTML/XHTML 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 eqn 7 ,
+.Xr man 7 ,
+.Xr mandoc_char 7 ,
+.Xr mdoc 7 ,
+.Xr roff 7 ,
+.Xr tbl 7
+.Sh AUTHORS
+The
+.Nm
+utility was written by
+.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
+.Sh CAVEATS
+In
+.Fl T Ns Cm html
+and
+.Fl T Ns Cm xhtml ,
+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.