Strip empty-line markers from mdoc.template and its mdoc.7 embedded form

[mandoc.git] / mdoc.7

diff --git a/mdoc.7 b/mdoc.7
index d7ea42531a45fdb842390bb64474e4619cb66bc7..184ccf737fcdbabe32a091c02ff00f026923c6e6 100644 (file)
--- a/mdoc.7
+++ b/mdoc.7
@@ -1,6 +1,6 @@
-.\"    $Id: mdoc.7,v 1.26 2009/06/11 20:02:37 kristaps Exp $
+.\"    $Id: mdoc.7,v 1.113 2010/06/02 12:01:00 kristaps Exp $

 .\"
 .\"

-.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
+.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@bsd.lv>

 .\"
 .\" 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


@@ -13,69 +13,54 @@
 .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 .\" 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 11 2009 $
+.\"
+.Dd $Mdocdate: June 2 2010 $

 .Dt MDOC 7
 .Os
 .Dt MDOC 7
 .Os

-.\" SECTION

 .Sh NAME
 .Nm mdoc
 .Nd mdoc language reference
 .Sh NAME
 .Nm mdoc
 .Nd mdoc language reference

-.\" SECTION

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

-language is used to format 
-.Bx 
+language is used to format
+.Bx

 .Ux
 .Ux

-manuals.  In this reference document, we describe the syntax, ontology
-and structure of the 
-.Nm
-language.
-.\" PARAGRAPH
+manuals.  In this reference document, we describe its syntax, structure,
+and usage.  Our reference implementation is mandoc; the
+.Sx COMPATIBILITY
+section describes compatibility with other troff \-mdoc implementations.

 .Pp
 An
 .Nm
 document follows simple rules:  lines beginning with the control
 .Pp
 An
 .Nm
 document follows simple rules:  lines beginning with the control

-character 
+character

 .Sq \.
 are parsed for macros.  Other lines are interpreted within the scope of
 prior macros:
 .Sq \.
 are parsed for macros.  Other lines are interpreted within the scope of
 prior macros:

-.Bd -literal -offset XXX
+.Bd -literal -offset indent

 \&.Sh Macro lines change control state.
 Other lines are interpreted within the current state.
 .Ed
 \&.Sh Macro lines change control state.
 Other lines are interpreted within the current state.
 .Ed

-.\" SECTION
-.Sh INPUT ENCODING
+.Sh LANGUAGE SYNTAX

 .Nm
 documents may contain only graphable 7-bit ASCII characters, the space
 .Nm
 documents may contain only graphable 7-bit ASCII characters, the space

-character
-.Sq \  ,
-and, in certain circumstances, the tab character
-.Sq \et .
-All manuals must have
-.Sq \en
-line termination.  
-.Pp
-The only time a blank line is acceptable is within
-the context of 
-.Sq \&.Bd \-literal
-or
-.Sq \&.Bd \-unfilled .
-.Pp
-Tab characters 
-.Pq \et
-are only acceptable when delimiting 
-.Sq \&.Bl \-column 
-and in
-.Sq \&.Bd \-literal
-or
-.Sq \&.Bd \-unfilled
-contexts.
-.\" SUB-SECTION
+character, and, in certain circumstances, the tab character.  All
+manuals must have
+.Ux
+line terminators.
+.Ss Comments
+Text following a
+.Sq \e" ,
+whether in a macro or free-form text line, is ignored to the end of
+line.  A macro line with only a control character and comment escape,
+.Sq \&.\e" ,
+is also ignored.  Macro lines with only a control charater and optionally
+whitespace are stripped from input.

 .Ss Reserved Characters
 Within a macro line, the following characters are reserved:
 .Ss Reserved Characters
 Within a macro line, the following characters are reserved:

-.Bl -tag -width 12n -offset XXXX -compact
+.Pp
+.Bl -tag -width Ds -offset indent -compact

 .It \&.
 .Pq period
 .It \&,
 .It \&.
 .Pq period
 .It \&,


@@ -95,510 +80,2000 @@ Within a macro line, the following characters are reserved:
 .It \&?
 .Pq question
 .It \&!
 .It \&?
 .Pq question
 .It \&!

-.Pq exclamation 
+.Pq exclamation
+.It \&|
+.Pq vertical bar

 .El
 .El

-.\" PARAGRAPH

 .Pp
 Use of reserved characters is described in
 .Pp
 Use of reserved characters is described in

-.Sx Closure .
-For general non-reserved use, characters must either be escaped with a
-non-breaking space
+.Sx MACRO SYNTAX .
+For general use in macro lines, these characters must either be escaped
+with a non-breaking space

 .Pq Sq \e&
 .Pq Sq \e&

-or, if applicable, an appropriate escape-sequence used.  
-.\" SUB-SECTION
+or, if applicable, an appropriate escape sequence used.

 .Ss Special Characters
 .Ss Special Characters

-Special character sequences begin with the escape character
+Special characters may occur in both macro and free-form lines.
+Sequences begin with the escape character

 .Sq \e
 .Sq \e

-followed by either an open-parenthesis 
+followed by either an open-parenthesis

 .Sq \&(
 for two-character sequences; an open-bracket
 .Sq \&[
 for n-character sequences (terminated at a close-bracket
 .Sq \&] ) ;
 or a single one-character sequence.
 .Sq \&(
 for two-character sequences; an open-bracket
 .Sq \&[
 for n-character sequences (terminated at a close-bracket
 .Sq \&] ) ;
 or a single one-character sequence.

+See
+.Xr mandoc_char 7
+for a complete list.
+Examples include
+.Sq \e(em
+.Pq em-dash
+and
+.Sq \ee
+.Pq back-slash .
+.Ss Text Decoration
+Terms may be text-decorated using the
+.Sq \ef
+escape followed by an indicator: B (bold), I, (italic), R (Roman), or P
+(revert to previous mode):

 .Pp
 .Pp

-Characters may alternatively be escaped by a slash-asterisk,
-.Sq \e* ,
-with the same combinations as described above.  This form is deprecated.  
-.\" SECTION
-.Sh STRUCTURE
-Macros are classified in an ontology described by their scope rules.
-Some macros are allowed to deviate from their classifications to
-preserve backward-compatibility with old macro combinations still found
-in the manual corpus.  These are specifically noted on a per-macro
-basis.
-.\" SUB-SECTION
-.Ss Scope
-.Bl -inset 
-.\" LIST-ITEM
-.It Em Block
-macros enclose other block macros, in-line macros or text, and
-may span multiple lines.
-.Bl -inset -offset XXXX
-.\" LIST-ITEM
-.It Em Full-block
-macros always span multiple lines.  They consist of zero or 
-more
-.Qq heads ,
-subsequent macros or text on the same line following invocation; an
-optional
-.Qq body ,
-which spans subsequent lines of text or macros; and an optional
-.Qq tail ,
-macros or text on the same line following closure.
-.\" LIST-ITEM
-.It Em Partial-block
-macros may span multiple lines.  They consists of a optional
-.Qq head ,
-text immediately following invocation; always a 
-.Qq body ,
-text or macros following the head on the same and subsequent lines; and
-optionally a
-.Qq tail ,
-text immediately following closure.
-.\" LIST-ITEM
-.It Em In-line
-macros may only enclose text and span at most a single line. 
-.El
-.El
-.\" SUB-SECTION
-.Ss Closure
-Closure of a macro's scope depends first on its classification, then
-on whether it's parsable.  In this table,
-.Sq BFE
-refers to block full-explicit and so on.
-.\" PARAGRAPH
-.Pp
-.Bl -tag -width 12n -offset XXXX -compact
-.It BPE , BFE
-corresponding explicit closure macro
-.It BFI
-end-of-file or a corresponding implicit closure macro
-.It BPI
-end-of-line (body may be closed by >0 space-separated
-.Sx Reserved Characters ,
-although block scope will still be open)
-.It INL
-end-of-line
-.El
-.\" PARAGRAPH
+.D1 \efBbold\efR \efIitalic\efP

 .Pp
 .Pp

-If a macro (block or in-line) is parsable, it may also be closed out by
-one of the following scenarios (unless specifically noted otherwise):
-.\" PARAGRAPH
+A numerical representation 3, 2, or 1 (bold, italic, and Roman,
+respectively) may be used instead.
+A text decoration is valid within
+the current font scope only:  if a macro opens a font scope alongside
+its own scope, such as
+.Sx \&Bf
+.Cm \&Sy ,
+in-scope invocations of
+.Sq \ef
+are only valid within the font scope of the macro.
+If
+.Sq \ef
+is specified outside of any font scope, such as in unenclosed, free-form
+text, it will affect the remainder of the document.

 .Pp
 .Pp

-.Bl -dash -offset XXXX -compact
-.It 
-a sequence of >0 space-separated
-.Sx Reserved Characters ,
-.It
-another macro,
-.It
-end-of-line, or
-.It
-completion of a set number of arguments.
+Text may also be sized with the
+.Sq \es
+escape, whose syntax is one of
+.Sq \es+-n
+for one-digit numerals;
+.Sq \es(+-nn
+or
+.Sq \es+-(nn
+for two-digit numerals; and
+.Sq \es[+-N] ,
+.Sq \es+-[N] ,
+.Sq \es'+-N' ,
+or
+.Sq \es+-'N'
+for arbitrary-digit numerals:
+.Pp
+.D1 \es+1bigger\es-1
+.D1 \es[+10]much bigger\es[-10]
+.D1 \es+(10much bigger\es-(10
+.D1 \es+'100'much much bigger\es-'100'
+.Pp
+Note these forms are
+.Em not
+recommended for
+.Nm ,
+which encourages semantic annotation.
+.Ss Predefined Strings
+Historically,
+.Xr groff 1
+also defined a set of package-specific
+.Dq predefined strings ,
+which, like
+.Sx Special Characters ,
+demark special output characters and strings by way of input codes.
+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] .
+See
+.Xr mandoc_char 7
+for a complete list.
+Examples include
+.Sq \e*(Am
+.Pq ampersand
+and
+.Sq \e*(Ba
+.Pq vertical bar .
+.Ss Whitespace
+Whitespace consists of the space character.
+In free-form lines, whitespace is preserved within a line; un-escaped
+trailing spaces are stripped from input (unless in a literal context).
+Blank free-form lines, which may include whitespace, are only permitted
+within literal contexts.
+.Pp
+In macro lines, whitespace delimits arguments and is discarded.
+If arguments are quoted, whitespace within the quotes is retained.
+.Ss Quotation
+Macro arguments may be quoted with a double-quote to group
+space-delimited terms or to retain blocks of whitespace.
+A quoted argument begins with a double-quote preceded by whitespace.
+The next double-quote not pair-wise adjacent to another double-quote
+terminates the literal, regardless of surrounding whitespace.
+.Pp
+This produces tokens
+.Sq a" ,
+.Sq b c ,
+.Sq de ,
+and
+.Sq fg" .
+Note that any quoted term, be it argument or macro, is indiscriminately
+considered literal text.
+Thus, the following produces
+.Sq \&Em a :
+.Bd -literal -offset indent
+\&.Em "Em a"
+.Ed
+.Pp
+In free-form mode, quotes are regarded as opaque text.
+.Ss Dates
+There are several macros in
+.Nm
+that require a date argument.
+The canonical form for dates is the American format:
+.Pp
+.D1 Cm Month Day , Year
+.Pp
+The
+.Cm Day
+value is an optionally zero-padded numeral.
+The
+.Cm Month
+value is the full month name.
+The
+.Cm Year
+value is the full four-digit year.
+.Pp
+Reduced form dates are broken-down canonical form dates:
+.Pp
+.D1 Cm Month , Year
+.D1 Cm Year
+.Pp
+Some examples of valid dates follow:
+.Pp
+.D1 "May, 2009" Pq reduced form
+.D1 "2009" Pq reduced form
+.D1 "May 20, 2009" Pq canonical form
+.Ss Scaling Widths
+Many macros support scaled widths for their arguments, such as
+stipulating a two-inch list indentation with the following:
+.Bd -literal -offset indent
+\&.Bl -tag -width 2i
+.Ed
+.Pp
+The syntax for scaled widths is
+.Sq Li [+-]?[0-9]*.[0-9]*[:unit:] ,
+where a decimal must be preceded or proceeded by at least one digit.
+Negative numbers, while accepted, are truncated to zero.
+The following scaling units are accepted:
+.Pp
+.Bl -tag -width Ds -offset indent -compact
+.It c
+centimetre
+.It i
+inch
+.It P
+pica (~1/6 inch)
+.It p
+point (~1/72 inch)
+.It f
+synonym for
+.Sq u
+.It v
+default vertical span
+.It m
+width of rendered
+.Sq m
+.Pq em
+character
+.It n
+width of rendered
+.Sq n
+.Pq en
+character
+.It u
+default horizontal span
+.It M
+mini-em (~1/100 em)

 .El
 .El

-.\" PARAGRAPH

 .Pp
 .Pp

-If >0 space-separated
-.Sx Reserved Characters
-are followed by non-reserved characters, the behaviour differs per
-macro.  In general, scope of the macro is closed and re-opened:
-subsequent tokens are interpreted as if the scope had just been opened.
-In other circumstances, scope is simply closed out.
-.\" SECTION
-.Sh SYNTAX
-Macros are two or three characters in length.  The syntax of macro
-invocation depends on its classification.  
-.Qq \-arg
-refers to the macro arguments (which may contain zero or more values).
-In these illustrations, 
-.Sq \&.Yo
-opens the scope of a macro, and if specified,
-.Sq \&.Yc
-closes it out (closure may be implicit at end-of-line or end-of-file).
-.\" PARAGRAPH
-.Pp
-Block full-explicit (may contain head, body, tail).
-.Bd -literal -offset XXXX
-\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBhead...\(rB 
-\(lBbody...\(rB 
-\&.Yc \(lBtail...\(rB 
+Using anything other than
+.Sq m ,
+.Sq n ,
+.Sq u ,
+or
+.Sq v
+is necessarily non-portable across output media.
+See
+.Sx COMPATIBILITY .
+.Ss Sentence Spacing
+When composing a manual, make sure that your sentences end at the end of
+a line.
+By doing so, front-ends will be able to apply the proper amount of
+spacing after the end of sentence (unescaped) period, exclamation mark,
+or question mark followed by zero or more non-sentence closing
+delimiters (
+.Ns Sq \&) ,
+.Sq \&] ,
+.Sq \&' ,
+.Sq \&" ) .
+.Pp
+The proper spacing is also intelligently preserved if a sentence ends at
+the boundary of a macro line, e.g.,
+.Pp
+.D1 \&Xr mandoc 1 \.
+.D1 \&Fl T \&Ns \&Cm ascii \.
+.Sh MANUAL STRUCTURE
+A well-formed
+.Nm
+document consists of a document prologue followed by one or more
+sections.
+.Pp
+The prologue, which consists of (in order) the
+.Sx \&Dd ,
+.Sx \&Dt ,
+and
+.Sx \&Os
+macros, is required for every document.
+.Pp
+The first section (sections are denoted by
+.Sx \&Sh )
+must be the NAME section, consisting of at least one
+.Sx \&Nm
+followed by
+.Sx \&Nd .
+.Pp
+Following that, convention dictates specifying at least the SYNOPSIS and
+DESCRIPTION sections, although this varies between manual sections.
+.Pp
+The following is a well-formed skeleton
+.Nm
+file:
+.Bd -literal -offset indent
+\&.Dd $\&Mdocdate$
+\&.Dt mdoc 7
+\&.Os
+\&.Sh NAME
+\&.Nm foo
+\&.Nd a description goes here
+\&.\e\*q The next is for sections 2, 3, & 9 only.
+\&.\e\*q .Sh LIBRARY
+\&.Sh SYNOPSIS
+\&.Nm foo
+\&.Op Fl options
+\&.Ar
+\&.Sh DESCRIPTION
+The
+\&.Nm
+utility processes files ...
+\&.\e\*q .Sh IMPLEMENTATION NOTES
+\&.\e\*q The next is for sections 2, 3, & 9 only.
+\&.\e\*q .Sh RETURN VALUES
+\&.\e\*q The next is for sections 1, 6, 7, & 8 only.
+\&.\e\*q .Sh ENVIRONMENT
+\&.\e\*q .Sh FILES
+\&.\e\*q The next is for sections 1 & 8 only.
+\&.\e\*q .Sh EXIT STATUS
+\&.\e\*q .Sh EXAMPLES
+\&.\e\*q The next is for sections 1, 4, 6, 7, & 8 only.
+\&.\e\*q .Sh DIAGNOSTICS
+\&.\e\*q The next is for sections 2, 3, & 9 only.
+\&.\e\*q .Sh ERRORS
+\&.\e\*q .Sh SEE ALSO
+\&.\e\*q .Xr foobar 1
+\&.\e\*q .Sh STANDARDS
+\&.\e\*q .Sh HISTORY
+\&.\e\*q .Sh AUTHORS
+\&.\e\*q .Sh CAVEATS
+\&.\e\*q .Sh BUGS
+\&.\e\*q .Sh SECURITY CONSIDERATIONS

 .Ed
 .Ed

-.\" PARAGRAPH

 .Pp
 .Pp

-Block full-implicit (may contain zero or more heads, body, no tail).
-.Bd -literal -offset XXXX
-\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB 
-\(lBbody...\(rB 
-\&.Yc
+The sections in a
+.Nm
+document are conventionally ordered as they appear above.
+Sections should be composed as follows:
+.Bl -ohang -offset Ds
+.It Em NAME
+The name(s) and a short description of the documented material.
+The syntax for this as follows:
+.Bd -literal -offset indent
+\&.Nm name0
+\&.Nm name1
+\&.Nm name2
+\&.Nd a short description

 .Ed
 .Ed

-.\" PARAGRAPH

 .Pp
 .Pp

-Block partial-explicit (may contain head, multi-line body, tail).
-.Bd -literal -offset XXXX
-\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBhead...\(rB 
-\(lBbody...\(rB 
-\&.Yc \(lBtail...\(rB 
-
-\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBhead...\(rB \
-\(lBbody...\(rB \&Yc \(lBtail...\(rB 
+The
+.Sx \&Nm
+macro(s) must precede the
+.Sx \&Nd
+macro.
+.Pp
+See
+.Sx \&Nm
+and
+.Sx \&Nd .
+.It Em LIBRARY
+The name of the library containing the documented material, which is
+assumed to be a function in a section 2, 3, or 9 manual.
+The syntax for this is as follows:
+.Bd -literal -offset indent
+\&.Lb libarm
+.Ed
+.Pp
+See
+.Sx \&Lb .
+.It Em SYNOPSIS
+Documents the utility invocation syntax, function call syntax, or device
+configuration.
+.Pp
+For the first, utilities (sections 1, 6, and 8), this is
+generally structured as follows:
+.Bd -literal -offset indent
+\&.Nm foo
+\&.Op Fl v
+\&.Op Fl o Ar file
+\&.Op Ar
+\&.Nm bar
+\&.Op Fl v
+\&.Op Fl o Ar file
+\&.Op Ar

 .Ed
 .Ed

-.\" PARAGRAPH
-.Pp
-Block partial-implicit (no head, body, no tail).  Note that the body
-section may be followed by zero or more 
-.Sx Reserved Words .
-These are in the block scope, but not in the body scope.
-.Bd -literal -offset XXXX
-\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBreserved...\(rB
+.Pp
+For the second, function calls (sections 2, 3, 9):
+.Bd -literal -offset indent
+\&.Vt extern const char *global;
+\&.In header.h
+\&.Ft "char *"
+\&.Fn foo "const char *src"
+\&.Ft "char *"
+\&.Fn bar "const char *src"

 .Ed
 .Ed

-.\" PARAGRAPH

 .Pp
 .Pp

-In-lines have \(>=0 scoped arguments.
-.Bd -literal -offset XXX
-\&.Yy \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB
-
-\&.Yy \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
+And for the third, configurations (section 4):
+.Bd -literal -offset indent
+\&.Cd \*qit* at isa? port 0x2e\*q
+\&.Cd \*qit* at isa? port 0x4e\*q

 .Ed
 .Ed

-.\"
-.Sh MACROS
-This section contains a complete list of all 
-.Nm
-macros, arranged ontologically.  A 
-.Qq callable
-macro is invoked subsequent to the initial macro-line macro.  A
-.Qq parsable
-macro may be followed by further (ostensibly callable) macros.
-.\" SUB-SECTION
+.Pp
+Manuals not in these sections generally don't need a
+.Em SYNOPSIS .
+.Pp
+See
+.Sx \&Op ,
+.Sx \&Cd ,
+.Sx \&Fn ,
+.Sx \&Ft ,
+and
+.Sx \&Vt .
+.It Em DESCRIPTION
+This expands upon the brief, one-line description in
+.Em NAME .
+It usually contains a break-down of the options (if documenting a
+command), such as:
+.Bd -literal -offset indent
+The arguments are as follows:
+\&.Bl \-tag \-width Ds
+\&.It Fl v
+Print verbose information.
+\&.El
+.Ed
+.Pp
+Manuals not documenting a command won't include the above fragment.
+.It Em IMPLEMENTATION NOTES
+Implementation-specific notes should be kept here.
+This is useful when implementing standard functions that may have side
+effects or notable algorithmic implications.
+.It Em RETURN VALUES
+This section is the dual of
+.Em EXIT STATUS ,
+which is used for commands.
+It documents the return values of functions in sections 2, 3, and 9.
+.Pp
+See
+.Sx \&Rv .
+.It Em ENVIRONMENT
+Documents any usages of environment variables, e.g.,
+.Xr environ 7 .
+.Pp
+See
+.Sx \&Ev .
+.It Em FILES
+Documents files used.
+It's helpful to document both the file and a short description of how
+the file is used (created, modified, etc.).
+.Pp
+See
+.Sx \&Pa .
+.It Em EXIT STATUS
+Command exit status for section 1, 6, and 8 manuals.
+This section is the dual of
+.Em RETURN VALUES ,
+which is used for functions.
+Historically, this information was described in
+.Em DIAGNOSTICS ,
+a practise that is now discouraged.
+.Pp
+See
+.Sx \&Ex .
+.It Em EXAMPLES
+Example usages.
+This often contains snippets of well-formed, well-tested invocations.
+Make doubly sure that your examples work properly!
+.It Em DIAGNOSTICS
+Documents error conditions.
+This is most useful in section 4 manuals.
+Historically, this section was used in place of
+.Em EXIT STATUS
+for manuals in sections 1, 6, and 8; however, this practise is
+discouraged.
+.Pp
+See
+.Sx \&Bl
+.Fl diag .
+.It Em ERRORS
+Documents error handling in sections 2, 3, and 9.
+.Pp
+See
+.Sx \&Er .
+.It Em SEE ALSO
+References other manuals with related topics.
+This section should exist for most manuals.
+Cross-references should conventionally be ordered first by section, then
+alphabetically.
+.Pp
+See
+.Sx \&Xr .
+.It Em STANDARDS
+References any standards implemented or used.
+If not adhering to any standards, the
+.Em HISTORY
+section should be used instead.
+.Pp
+See
+.Sx \&St .
+.It Em HISTORY
+The history of any manual without a
+.Em STANDARDS
+section should be described in this section.
+.It Em AUTHORS
+Credits to authors, if applicable, should appear in this section.
+Authors should generally be noted by both name and an e-mail address.
+.Pp
+See
+.Sx \&An .
+.It Em CAVEATS
+Explanations of common misuses and misunderstandings should be explained
+in this section.
+.It Em BUGS
+Extant bugs should be described in this section.
+.It Em SECURITY CONSIDERATIONS
+Documents any security precautions that operators should consider.
+.El
+.Sh MACRO SYNTAX
+Macros are one to three three characters in length and begin with a
+control character ,
+.Sq \&. ,
+at the beginning of the line.
+An arbitrary amount of whitespace may sit between the control character
+and the macro name.
+Thus, the following are equivalent:
+.Bd -literal -offset indent
+\&.Pp
+\&.\ \ \ \&Pp
+.Ed
+.Pp
+The syntax of a macro depends on its classification.
+In this section,
+.Sq \-arg
+refers to macro arguments, which may be followed by zero or more
+.Sq parm
+parameters;
+.Sq \&Yo
+opens the scope of a macro; and if specified,
+.Sq \&Yc
+closes it out.
+.Pp
+The
+.Em Callable
+column indicates that the macro may be called subsequent to the initial
+line-macro.
+If a macro is not callable, then its invocation after the initial line
+macro is interpreted as opaque text, such that
+.Sq \&.Fl \&Sh
+produces
+.Sq Fl \&Sh .
+.Pp
+The
+.Em Parsable
+column indicates whether the macro may be followed by further
+(ostensibly callable) macros.
+If a macro is not parsable, subsequent macro invocations on the line
+will be interpreted as opaque text.
+.Pp
+The
+.Em Scope
+column, if applicable, describes closure rules.
+.Ss Block full-explicit
+Multi-line scope closed by an explicit closing macro.
+All macros contains bodies; only
+.Sx \&Bf
+contains a head.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
+\(lBbody...\(rB
+\&.Yc
+.Ed
+.Pp
+.Bl -column -compact -offset indent "MacroX" "CallableX" "ParsableX" "closed by XXX"
+.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope
+.It Sx \&Bd  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Ed
+.It Sx \&Bf  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Ef
+.It Sx \&Bk  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Ek
+.It Sx \&Bl  Ta    \&No     Ta    \&No     Ta    closed by Sx \&El
+.It Sx \&Ed  Ta    \&No     Ta    \&No     Ta    opened by Sx \&Bd
+.It Sx \&Ef  Ta    \&No     Ta    \&No     Ta    opened by Sx \&Bf
+.It Sx \&Ek  Ta    \&No     Ta    \&No     Ta    opened by Sx \&Bk
+.It Sx \&El  Ta    \&No     Ta    \&No     Ta    opened by Sx \&Bl
+.El

 .Ss Block full-implicit
 .Ss Block full-implicit

-The head of these macros follows invocation; the body is the content of
-subsequent lines prior to closure.  None of these macros have tails;
-some 
+Multi-line scope closed by end-of-file or implicitly by another macro.
+All macros have bodies; some
+.Po
+.Sx \&It Fl bullet ,
+.Fl hyphen ,
+.Fl dash ,
+.Fl enum ,
+.Fl item
+.Pc
+don't have heads; only one

 .Po
 .Po

-.Sq \&.It \-bullet , 
-.Sq \-hyphen , 
-.Sq \-dash ,
-.Sq \-enum ,
-.Sq \-item 
+.Sx \&It Fl column

 .Pc
 .Pc

-don't have heads.
+has multiple heads.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB
+\(lBbody...\(rB
+.Ed

 .Pp
 .Pp

-.Bl -column "MacroX" "CallableX" "ParsableX" "Closing" -compact -offset XXXX
-.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Closing
-.It \&.Sh    Ta    \&No    Ta    \&No    Ta    \&.Sh
-.It \&.Ss    Ta    \&No    Ta    \&No    Ta    \&.Sh, \&.Ss
-.It \&.It    Ta    \&No    Ta    Yes     Ta    \&.It, \&.El
+.Bl -column -compact -offset indent "MacroX" "CallableX" "ParsableX" "closed by XXXXXXXXXXX"
+.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope
+.It Sx \&It  Ta    \&No     Ta    Yes      Ta    closed by Sx \&It , Sx \&El
+.It Sx \&Nd  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Sh
+.It Sx \&Sh  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Sh
+.It Sx \&Ss  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Sh , Sx \&Ss

 .El
 .El

-.\" SUB-SECTION
-.Ss Block full-explicit
-None of these macros are callable or parsed.  The last column indicates
-the explicit scope rules.  All contains bodies, some may contain heads 
-.Pq So \&Bf Sc .
+.Ss Block partial-explicit
+Like block full-explicit, but also with single-line scope.
+Each has at least a body and, in limited circumstances, a head
+.Po
+.Sx \&Fo ,
+.Sx \&Eo
+.Pc
+and/or tail
+.Pq Sx \&Ec .
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
+\(lBbody...\(rB
+\&.Yc \(lBtail...\(rB
+
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \
+\(lBbody...\(rB \&Yc \(lBtail...\(rB
+.Ed

 .Pp
 .Pp

-.Bl -column "MacroX" "CallableX" "ParsableX" "closed by XXX" -compact -offset XXXX
+.Bl -column "MacroX" "CallableX" "ParsableX" "closed by XXXX" -compact -offset indent

 .It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope
 .It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope

-.It \&.Bd    Ta    \&No    Ta    \&No    Ta    closed by \&.Ed
-.It \&.Ed    Ta    \&No    Ta    \&No    Ta    opened by \&.Bd
-.It \&.Bl    Ta    \&No    Ta    \&No    Ta    closed by \&.El
-.It \&.El    Ta    \&No    Ta    \&No    Ta    opened by \&.Bl
-.It \&.Bf    Ta    \&No    Ta    \&No    Ta    closed by \&.Ef
-.It \&.Ef    Ta    \&No    Ta    \&No    Ta    opened by \&.Bf
-.It \&.Bk    Ta    \&No    Ta    \&No    Ta    closed by \&.Ek
-.It \&.Ek    Ta    \&No    Ta    \&No    Ta    opened by \&.Bk
+.It Sx \&Ac  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Ao
+.It Sx \&Ao  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Ac
+.It Sx \&Bc  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Bo
+.It Sx \&Bo  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Bc
+.It Sx \&Brc Ta    Yes      Ta    Yes      Ta    opened by Sx \&Bro
+.It Sx \&Bro Ta    Yes      Ta    Yes      Ta    closed by Sx \&Brc
+.It Sx \&Dc  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Do
+.It Sx \&Do  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Dc
+.It Sx \&Ec  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Eo
+.It Sx \&Eo  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Ec
+.It Sx \&Fc  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Fo
+.It Sx \&Fo  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Fc
+.It Sx \&Oc  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Oo
+.It Sx \&Oo  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Oc
+.It Sx \&Pc  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Po
+.It Sx \&Po  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Pc
+.It Sx \&Qc  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Oo
+.It Sx \&Qo  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Oc
+.It Sx \&Re  Ta    \&No     Ta    \&No     Ta    opened by Sx \&Rs
+.It Sx \&Rs  Ta    \&No     Ta    \&No     Ta    closed by Sx \&Re
+.It Sx \&Sc  Ta    Yes      Ta    Yes      Ta    opened by Sx \&So
+.It Sx \&So  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Sc
+.It Sx \&Xc  Ta    Yes      Ta    Yes      Ta    opened by Sx \&Xo
+.It Sx \&Xo  Ta    Yes      Ta    Yes      Ta    closed by Sx \&Xc

 .El
 .El

-.\" SUB-SECTION

 .Ss Block partial-implicit
 .Ss Block partial-implicit

-All of these are callable and parsed for further macros.  Their scopes
-close at the invocation's end-of-line.
+Like block full-implicit, but with single-line scope closed by
+.Sx Reserved Characters
+or end of line.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB
+.Ed

 .Pp
 .Pp

-.Bl -column "MacroX" "CallableX" "ParsableX" -compact -offset XXXX
+.Bl -column "MacroX" "CallableX" "ParsableX" -compact -offset indent

 .It Em Macro Ta Em Callable Ta Em Parsable
 .It Em Macro Ta Em Callable Ta Em Parsable

-.It \&.Aq    Ta    Yes   Ta    Yes
-.It \&.Op    Ta    Yes   Ta    Yes
-.It \&.Bq    Ta    Yes   Ta    Yes
-.It \&.Dq    Ta    Yes   Ta    Yes
-.It \&.Pq    Ta    Yes   Ta    Yes
-.It \&.Qq    Ta    Yes   Ta    Yes
-.It \&.Sq    Ta    Yes   Ta    Yes
-.It \&.Brq   Ta    Yes   Ta    Yes
-.It \&.D1    Ta    \&No  Ta    \&Yes
-.It \&.Dl    Ta    \&No  Ta    Yes
-.It \&.Ql    Ta    Yes   Ta    Yes
+.It Sx \&Aq  Ta    Yes      Ta    Yes
+.It Sx \&Bq  Ta    Yes      Ta    Yes
+.It Sx \&Brq Ta    Yes      Ta    Yes
+.It Sx \&D1  Ta    \&No     Ta    \&Yes
+.It Sx \&Dl  Ta    \&No     Ta    Yes
+.It Sx \&Dq  Ta    Yes      Ta    Yes
+.It Sx \&Op  Ta    Yes      Ta    Yes
+.It Sx \&Pq  Ta    Yes      Ta    Yes
+.It Sx \&Ql  Ta    Yes      Ta    Yes
+.It Sx \&Qq  Ta    Yes      Ta    Yes
+.It Sx \&Sq  Ta    Yes      Ta    Yes
+.It Sx \&Vt  Ta    Yes      Ta    Yes

 .El
 .El

-.\" PARAGRAPH

 .Pp
 .Pp

-The
-.Sq \&.Op
-may be broken by 
-.Sq \&.Oc 
-as in the following example:
-.Bd -literal -offset XXXX
-\&.Oo
-\&.Op Fl a Oc
+Note that the
+.Sx \&Vt
+macro is a
+.Sx Block partial-implicit
+only when invoked as the first macro
+in a
+.Em SYNOPSIS
+section line, else it is
+.Sx In-line .
+.Ss In-line
+Closed by
+.Sx Reserved Characters ,
+end of line, fixed argument lengths, and/or subsequent macros.
+In-line macros have only text children.
+If a number (or inequality) of arguments is
+.Pq n ,
+then the macro accepts an arbitrary number of arguments.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB \(lbres...\(rb
+
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc...
+
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN

 .Ed
 .Pp
 .Ed
 .Pp

-In the above example, the scope of
-.Sq \&.Op
-is technically broken by 
-.Sq \&.Oc ,
-however, due to the overwhelming existence of this sequence, it's
-allowed.
-.\" SUB-SECTION
-.Ss Block partial-explicit
-Each of these contains at least a body and, in limited circumstances, a
-head 
-.Pq So \&.Fo Sc , So \&.Eo Sc
-and/or tail 
-.Pq So \&.Ec Sc .
+.Bl -column "MacroX" "CallableX" "ParsableX" "Arguments" -compact -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Arguments
+.It Sx \&%A  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%B  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%C  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%D  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%I  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%J  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%N  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%O  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%P  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%Q  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%R  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%T  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%U  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&%V  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&Ad  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&An  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Ap  Ta    Yes      Ta    Yes      Ta    0
+.It Sx \&Ar  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&At  Ta    Yes      Ta    Yes      Ta    1
+.It Sx \&Bsx Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Bt  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Bx  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Cd  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Cm  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Db  Ta    \&No     Ta    \&No     Ta    1
+.It Sx \&Dd  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&Dt  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Dv  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Dx  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Em  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&En  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Er  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Es  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Ev  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Ex  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Fa  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Fd  Ta    \&No     Ta    \&No     Ta    >0
+.It Sx \&Fl  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Fn  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Fr  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Ft  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Fx  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Hf  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Ic  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&In  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Lb  Ta    \&No     Ta    \&No     Ta    1
+.It Sx \&Li  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Lk  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Lp  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Ms  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Mt  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Nm  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&No  Ta    Yes      Ta    Yes      Ta    0
+.It Sx \&Ns  Ta    Yes      Ta    Yes      Ta    0
+.It Sx \&Nx  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Os  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Ot  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Ox  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Pa  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Pf  Ta    Yes      Ta    Yes      Ta    1
+.It Sx \&Pp  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Rv  Ta    \&No     Ta    \&No     Ta    n
+.It Sx \&Sm  Ta    \&No     Ta    \&No     Ta    1
+.It Sx \&St  Ta    \&No     Ta    Yes      Ta    1
+.It Sx \&Sx  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Sy  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Tn  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Ud  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&Ux  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Va  Ta    Yes      Ta    Yes      Ta    n
+.It Sx \&Vt  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&Xr  Ta    Yes      Ta    Yes      Ta    >0
+.It Sx \&br  Ta    \&No     Ta    \&No     Ta    0
+.It Sx \&sp  Ta    \&No     Ta    \&No     Ta    1
+.El
+.Sh REFERENCE
+This section is a canonical reference of all macros, arranged
+alphabetically.
+For the scoping of individual macros, see
+.Sx MACRO SYNTAX .
+.Ss \&%A
+Author name of an
+.Sx \&Rs
+block.  Multiple authors should each be accorded their own
+.Sx \%%A
+line.  Author names should be ordered with full or abbreviated
+forename(s) first, then full surname.
+.Ss \&%B
+Book title of an
+.Sx \&Rs
+block.  This macro may also be used in a non-bibliographic context when
+referring to book titles.
+.Ss \&%C
+Publication city or location of an
+.Sx \&Rs
+block.

 .Pp
 .Pp

-.Bl -column "MacroX" "CallableX" "ParsableX" "closed by XXXX" -compact -offset XXXX
-.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope
-.It \&.Ao    Ta    Yes   Ta    Yes    Ta    closed by \&.Ac
-.It \&.Ac    Ta    Yes   Ta    Yes    Ta    opened by \&.Ao
-.It \&.Bc    Ta    Yes   Ta    Yes    Ta    closed by \&.Bo
-.It \&.Bo    Ta    Yes   Ta    Yes    Ta    opened by \&.Bc
-.It \&.Pc    Ta    Yes   Ta    Yes    Ta    closed by \&.Po
-.It \&.Po    Ta    Yes   Ta    Yes    Ta    opened by \&.Pc
-.It \&.Do    Ta    Yes   Ta    Yes    Ta    closed by \&.Dc
-.It \&.Dc    Ta    Yes   Ta    Yes    Ta    opened by \&.Do
-.It \&.Xo    Ta    Yes   Ta    Yes    Ta    closed by \&.Xc
-.It \&.Xc    Ta    Yes   Ta    Yes    Ta    opened by \&.Xo
-.It \&.Bro   Ta    Yes   Ta    Yes    Ta    closed by \&.Brc
-.It \&.Brc   Ta    Yes   Ta    Yes    Ta    opened by \&.Bro
-.It \&.Oc    Ta    Yes   Ta    Yes    Ta    closed by \&.Oo
-.It \&.Oo    Ta    Yes   Ta    Yes    Ta    opened by \&.Oc
-.It \&.So    Ta    Yes   Ta    Yes    Ta    closed by \&.Sc
-.It \&.Sc    Ta    Yes   Ta    Yes    Ta    opened by \&.So
-.It \&.Fc    Ta    Yes   Ta    Yes    Ta    opened by \&.Fo
-.It \&.Fo    Ta    \&No  Ta    \&No   Ta    closed by \&.Fc
-.It \&.Ec    Ta    Yes   Ta    Yes    Ta    opened by \&.Eo
-.It \&.Eo    Ta    Yes   Ta    Yes    Ta    closed by \&.Ec
-.It \&.Qc    Ta    Yes   Ta    Yes    Ta    opened by \&.Oo
-.It \&.Qo    Ta    Yes   Ta    Yes    Ta    closed by \&.Oc
-.It \&.Re    Ta    \&No  Ta    \&No   Ta    opened by \&.Rs
-.It \&.Rs    Ta    \&No  Ta    \&No   Ta    closed by \&.Re
+.Em Remarks :
+this macro is not implemented in
+.Xr groff 1 .
+.Ss \&%D
+Publication date of an
+.Sx \&Rs
+block.  This should follow the reduced or canonical form syntax
+described in
+.Sx Dates .
+.Ss \&%I
+Publisher or issuer name of an
+.Sx \&Rs
+block.
+.Ss \&%J
+Journal name of an
+.Sx \&Rs
+block.
+.Ss \&%N
+Issue number (usually for journals) of an
+.Sx \&Rs
+block.
+.Ss \&%O
+Optional information of an
+.Sx \&Rs
+block.
+.Ss \&%P
+Book or journal page number of an
+.Sx \&Rs
+block.
+.Ss \&%Q
+Institutional author (school, government, etc.) of an
+.Sx \&Rs
+block.  Multiple institutional authors should each be accorded their own
+.Sx \&%Q
+line.
+.Ss \&%R
+Technical report name of an
+.Sx \&Rs
+block.
+.Ss \&%T
+Article title of an
+.Sx \&Rs
+block.  This macro may also be used in a non-bibliographical context
+when referring to article titles.
+.Ss \&%U
+URI of reference document.
+.Ss \&%V
+Volume number of an
+.Sx \&Rs
+block.
+.Ss \&Ac
+Closes an
+.Sx \&Ao
+block.  Does not have any tail arguments.
+.Ss \&Ad
+Address construct: usually in the context of an computational address in
+memory, not a physical (post) address.
+.Pp
+Examples:
+.D1 \&.Ad [0,$]
+.D1 \&.Ad 0x00000000
+.Ss \&An
+Author name.
+This macro may alternatively accepts the following arguments, although
+these may not be specified along with a parameter:
+.Bl -tag -width 12n -offset indent
+.It Fl split
+Renders a line break before each author listing.
+.It Fl nosplit
+The opposite of
+.Fl split .

 .El
 .El

-.\" SUB-SECTION
-.Ss In-line 
-In-line macros have only text children.  If a number (or inequality) of
-arguments is
-.Pq n , 
-then the macro accepts an arbitrary number of arguments.

 .Pp
 .Pp

-.Bl -column "MacroX" "CallableX" "ParsableX" "Arguments" -compact -offset XXXX
-.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Arguments
-.It \&.Dd    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.Dt    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Os    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Pp    Ta    \&No  Ta    \&No    Ta    0
-.It \&.Ad    Ta    Yes   Ta    Yes     Ta    n
-.It \&.An    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ar    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Cd    Ta    Yes   Ta    \&No    Ta    >0
-.It \&.Cm    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Dv    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Er    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Ev    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ex    Ta    \&No  Ta    \&No    Ta    0
-.It \&.Fa    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Fd    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.Fl    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Fn    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Ft    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ic    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.In    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Li    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Nd    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Nm    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ot    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Pa    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Rv    Ta    \&No  Ta    \&No    Ta    0
-.It \&.St    Ta    \&No  Ta    Yes     Ta    1
-.It \&.Va    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Vt    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Xr    Ta    Yes   Ta    Yes     Ta    >0, <3
-.It \&.%A    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%B    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%C    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%D    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%I    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%J    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%N    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%O    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%P    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%R    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%T    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.%V    Ta    \&No  Ta    \&No    Ta    >0
-.It \&.At    Ta    Yes   Ta    Yes     Ta    1
-.It \&.Bsx   Ta    Yes   Ta    Yes     Ta    n
-.It \&.Bx    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Db    Ta    \&No  Ta    \&No    Ta    1
-.It \&.Em    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Fx    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ms    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.No    Ta    Yes   Ta    Yes     Ta    0
-.It \&.Ns    Ta    Yes   Ta    Yes     Ta    0
-.It \&.Nx    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Ox    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Pf    Ta    \&No  Ta    Yes     Ta    1
-.It \&.Sm    Ta    \&No  Ta    \&No    Ta    1
-.It \&.Sx    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Sy    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Tn    Ta    Yes   Ta    Yes     Ta    >0
-.It \&.Ux    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Dx    Ta    Yes   Ta    Yes     Ta    n
-.It \&.Bt    Ta    \&No  Ta    \&No    Ta    0
-.It \&.Hf    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Fr    Ta    \&No  Ta    \&No    Ta    n
-.It \&.Ud    Ta    \&No  Ta    \&No    Ta    0
-.It \&.Lb    Ta    \&No  Ta    \&No    Ta    1
-.It \&.Ap    Ta    Yes   Ta    Yes     Ta    0
-.It \&.Lp    Ta    \&No  Ta    \&No    Ta    0
-.It \&.Lk    Ta    \&No  Ta    Yes     Ta    >0
-.It \&.Mt    Ta    \&No  Ta    Yes     Ta    >0
-.It \&.Es    Ta    \&No  Ta    \&No    Ta    0
-.It \&.En    Ta    \&No  Ta    \&No    Ta    0
+In the AUTHORS section, the default is not to split the first author
+listing, but all subsequent author listings, whether or not they're
+interspersed by other macros or text, are split.
+Thus, specifying
+.Fl split
+will cause the first listing also to be split.
+If not in the AUTHORS section, the default is not to split.
+.Pp
+Examples:
+.D1 \&.An -nosplit
+.D1 \&.An J. D. Ullman .
+.Pp
+.Em Remarks :
+the effects of
+.Fl split
+or
+.Fl nosplit
+are re-set when entering the AUTHORS section, so if one specifies
+.Sx \&An Fl nosplit
+in the general document body, it must be re-specified in the AUTHORS
+section.
+.Ss \&Ao
+Begins a block enclosed by angled brackets.
+Does not have any head arguments.
+.Pp
+Examples:
+.D1 \&.Fl -key= \&Ns \&Ao \&Ar val \&Ac
+.Pp
+See also
+.Sx \&Aq .
+.Ss \&Ap
+Inserts an apostrophe without any surrounding white-space.
+This is generally used as a grammatic device when referring to the verb
+form of a function:
+.Bd -literal -offset indent
+\&.Fn execve Ap d
+.Ed
+.Ss \&Aq
+Encloses its arguments in angled brackets.
+.Pp
+Examples:
+.D1 \&.Fl -key= \&Ns \&Aq \&Ar val
+.Pp
+.Em Remarks :
+this macro is often abused for rendering URIs, which should instead use
+.Sx \&Lk
+or
+.Sx \&Mt ,
+or to note pre-processor
+.Dq Li #include
+statements, which should use
+.Sx \&In .
+.Pp
+See also
+.Sx \&Ao .
+.Ss \&Ar
+Command arguments.
+If an argument is not provided, the string
+.Dq file ...
+is used as a default.
+.Pp
+Examples:
+.D1 \&.Fl o \&Ns \&Ar file1
+.D1 \&.Ar
+.D1 \&.Ar arg1 , arg2 .
+.Ss \&At
+Formats an AT&T version.
+Accepts at most one parameter:
+.Bl -tag -width 12n -offset indent
+.It Cm v[1-7] | 32v
+A version of
+.At .
+.It Cm V[.[1-4]]?
+A system version of
+.At .

 .El
 .Pp
 .El
 .Pp

-The
-.Sq \&.Ot ,
-.Sq \&.Fr ,
-.Sq \&.Es 
-and
-.Sq \&.En ,
-macros are obsolete.
-.\" SECTION
-.Sh COMPATIBILITY
-The mdoc language was traditionally a 
-.Qq roff
-macro package; most existing manuals were written with mdoc syntax
-dictated by system-dependent roff installations.  This section documents
-compatibility with these systems.
+Note that these parameters do not begin with a hyphen.

 .Pp
 .Pp

-.Bl -dash -compact
-.\" LIST-ITEM
-.It
-.Sq \&.An ,
-.Sq \&.Fo ,
-.Sq \&.Ms ,
+Examples:
+.D1 \&.At
+.D1 \&.At V.1
+.Pp
+See also
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+.Sx \&Ox ,

 and
 and

-.Sq \&.St
-historically weren't callable (they are now).
-.\" LIST-ITEM
+.Sx \&Ux .
+.Ss \&Bc
+Closes a
+.Sx \&Bo
+block.  Does not have any tail arguments.
+.Ss \&Bd
+Begins a display block.
+A display is collection of macros or text which may be collectively
+offset or justified in a manner different from that
+of the enclosing context.
+By default, the block is preceded by a vertical space.
+.Pp
+Each display is associated with a type, which must be one of the
+following arguments:
+.Bl -tag -width 12n -offset indent
+.It Fl ragged
+Only left-justify the block.
+.It Fl unfilled
+Do not justify the block at all.
+.It Fl filled
+Left- and right-justify the block.
+.It Fl literal
+Alias for
+.Fl unfilled .
+.It Fl centered
+Centre-justify each line.
+.El
+.Pp
+The type must be provided first.
+Secondary arguments are as follows:
+.Bl -tag -width 12n -offset indent
+.It Fl offset Ar width
+Offset by the value of
+.Ar width ,
+which is interpreted as one of the following, specified in order:
+.Bl -item

 .It
 .It

-.Sq \&.It \-nested
-is assumed for all lists: any list may be nested and
-.Sq \-enum
-lists will restart the sequence only for the sub-list.
-.\" LIST-ITEM
+As one of the pre-defined strings
+.Ar indent ,
+the width of standard indentation;
+.Ar indent-two ,
+twice
+.Ar indent ;
+.Ar left ,
+which has no effect ;
+.Ar right ,
+which justifies to the right margin; and
+.Ar center ,
+which aligns around an imagined centre axis.

 .It
 .It

-.Sq \&.It \-column
-syntax where column widths may be preceded by other arguments (instead
-of proceeded) is not supported.
-.\" LIST-ITEM
+As a precalculated width for a named macro.
+The most popular is the imaginary macro
+.Ar \&Ds ,
+which resolves to
+.Ar 6n .

 .It
 .It

-The 
-.Sq \&.At
-macro only accepts a single parameter.
-.\" LIST-ITEM
+As a scaling unit following the syntax described in
+.Sx Scaling Widths .

 .It
 .It

-The system-name macros (
-.Ns Sq \&.At ,
-.Sq \&.Bsx ,
-.Sq \&.Bx ,
-.Sq \&.Fx ,
-.Sq \&.Nx ,
-.Sq \&.Ox ,
+As the calculated string length of the opaque string.
+.El
+.Pp
+If unset, it will revert to the value of
+.Ar 8n
+as described in
+.Sx Scaling Widths .
+.It Fl compact
+Do not assert a vertical space before the block.
+.It Fl file Ar file
+Prepend the file
+.Ar file
+before any text or macros within the block.
+.El
+.Pp
+Examples:
+.Bd -literal -offset indent
+\&.Bd \-unfilled \-offset two-indent \-compact
+   Hello       world.
+\&.Ed
+.Ed
+.Pp
+See also
+.Sx \&D1

 and
 and

-.Sq \&.Ux )
-are callable.
-.\" LIST-ITEM
-.It
-Some manuals use
-.Sq \&.Li
-incorrectly by following it with a reserved character and expecting the
-delimiter to render.  This is not supported.
-.\" LIST-ITEM
-.It
-.Sq \&.Cd
-is callable.
+.Sx \&Dl .
+.Ss \&Bf
+.Ss \&Bk
+.Ss \&Bl
+Begins a list composed of one or more list entries.
+A list is associated with a type, which is a required argument.
+Other arguments are
+.Fl width ,
+defined per-type as accepting a literal or
+.Sx Scaling Widths
+value;
+.Fl offset ,
+also accepting a literal or
+.Sx Scaling Widths
+value setting the list's global offset; and
+.Fl compact ,
+suppressing the default vertical space printed before each list entry.
+A list entry is specified by the
+.Sx \&It
+macro, which consists of a head and optional body (depending on the list
+type).
+A list must specify one of the following list types:
+.Bl -tag -width 12n -offset indent
+.It Fl bullet
+A list offset by a bullet.
+The head of list entries must be empty.
+List entry bodies are positioned after the bullet.
+The
+.Fl width
+argument varies the width of list bodies' left-margins.
+.It Fl column
+A columnated list.
+The
+.Fl width
+argument has no effect.
+The number of columns is specified as parameters to the
+.Sx \&Bl
+macro.
+These dictate the width of columns either as
+.Sx Scaling Widths
+or literal text.
+List entry bodies must be left empty.
+Column bodies have the following syntax:
+.Pp
+.D1 .It col1 <TAB> ... coln
+.D1 .It col1 \&Ta ... coln
+.D1 .It col1 <TAB> col2 \&Ta coln
+.Pp
+where columns may be separated by tabs, the literal string
+.Qq \&Ta ,
+or a mixture of both.
+These are equivalent except that quoted sections propogate over tabs,
+for example,
+.Pp
+.D1 .It \(dqcol1 ; <TAB> col2 ;\(dq ;
+.Pp
+will preserve the semicolon whitespace except for the last.
+.It Fl dash
+A list offset by a dash (hyphen).
+The head of list entries must be empty.
+List entry bodies are positioned past the dash.
+The
+.Fl width
+argument varies the width of list bodies' left-margins.
+.It Fl diag
+Like
+.Fl inset ,
+but with additional formatting to the head.
+The
+.Fl width
+argument varies the width of list bodies' left-margins.
+.It Fl enum
+An enumerated list offset by the enumeration from 1.
+The head of list entries must be empty.
+List entry bodies are positioned after the enumeration.
+The
+.Fl width
+argument varies the width of list bodies' left-margins.
+.It Fl hang
+Like
+.Fl tag ,
+but instead of list bodies positioned after the head, they trail the
+head text.
+The
+.Fl width
+argument varies the width of list bodies' left-margins.
+.It Fl hyphen
+Synonym for
+.Fl dash .
+.It Fl inset
+List bodies follow the list head.
+The
+.Fl width
+argument is ignored.
+.It Fl item
+This produces blocks of text.
+The head of list entries must be empty.
+The
+.Fl width
+argument is ignored.
+.It Fl ohang
+List bodies are positioned on the line following the head.
+The
+.Fl width
+argument is ignored.
+.It Fl tag
+A list offset by list entry heads.  List entry bodies are positioned
+after the head as specified by the
+.Fl width
+argument.

 .El
 .El

-.\" SECTION
-.Sh SEE ALSO
-.Xr mandoc 1 ,
-.Xr mandoc_char 7
-.\" SECTION
-.Sh AUTHORS
+.Ss \&Bo
+Begins a block enclosed by square brackets.
+Does not have any head arguments.
+.Pp
+Examples:
+.Bd -literal -offset indent
+\&.Bo 1 ,
+\&.Dv BUFSIZ \&Bc
+.Ed
+.Pp
+See also
+.Sx \&Bq .
+.Ss \&Bq
+Encloses its arguments in square brackets.
+.Pp
+Examples:
+.D1 \&.Bq 1 , \&Dv BUFSIZ
+.Pp
+.Em Remarks :
+this macro is sometimes abused to emulate optional arguments for
+commands; the correct macros to use for this purpose are
+.Sx \&Op ,
+.Sx \&Oo ,
+and
+.Sx \&Oc .
+.Pp
+See also
+.Sx \&Bo .
+.Ss \&Brc
+Closes a
+.Sx \&Bro
+block.  Does not have any tail arguments.
+.Ss \&Bro
+Begins a block enclosed by curly braces.
+Does not have any head arguments.
+.Pp
+Examples:
+.Bd -literal -offset indent
+\&.Bro 1 , ... ,
+\&.Va n \&Brc
+.Ed
+.Pp
+See also
+.Sx \&Brq .
+.Ss \&Brq
+Encloses its arguments in curly braces.
+.Pp
+Examples:
+.D1 \&.Brq 1 , ... , \&Va n
+.Pp
+See also
+.Sx \&Bro .
+.Ss \&Bsx
+Format the BSD/OS version provided as an argument, or a default value if
+no argument is provided.
+.Pp
+Examples:
+.D1 \&.Bsx 1.0
+.D1 \&.Bsx
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+.Sx \&Ox ,
+and
+.Sx \&Ux .
+.Ss \&Bt
+Prints
+.Dq is currently in beta test.
+.Ss \&Bx
+Format the BSD version provided as an argument, or a default value if no
+argument is provided.
+.Pp
+Examples:
+.D1 \&.Bx 4.4
+.D1 \&.Bx
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+.Sx \&Ox ,
+and
+.Sx \&Ux .
+.Ss \&Cd
+Configuration declaration.
+This denotes strings accepted by
+.Xr config 8 .
+.Pp
+Examples:
+.D1 \&.Cd device le0 at scode?
+.Pp
+.Em Remarks :
+this macro is commonly abused by using quoted literals to retain
+white-space and align consecutive
+.Sx \&Cd
+declarations.
+This practise is discouraged.
+.Ss \&Cm
+Command modifiers.
+Useful when specifying configuration options or keys.
+.Pp
+Examples:
+.D1 \&.Cm ControlPath
+.D1 \&.Cm ControlMaster
+.Pp
+See also
+.Sx \&Fl .
+.Ss \&D1
+One-line indented display.
+This is formatted by the default rules and is useful for simple indented
+statements.
+It is followed by a newline.
+.Pp
+Examples:
+.D1 \&.D1 \&Fl abcdefgh
+.Pp
+See also
+.Sx \&Bd
+and
+.Sx \&Dl .
+.Ss \&Db
+.Ss \&Dc
+Closes a
+.Sx \&Do
+block.  Does not have any tail arguments.
+.Ss \&Dd
+Document date.
+This is the mandatory first macro of any
+.Nm
+manual.
+Its calling syntax is as follows:
+.Pp
+.D1 \. Ns Sx \&Dd Cm date
+.Pp

 The
 The

+.Cm date
+field may be either
+.Ar $\&Mdocdate$ ,
+which signifies the current manual revision date dictated by
+.Xr cvs 1 ,
+or instead a valid canonical date as specified by
+.Sx Dates .
+If a date does not conform, the current date is used instead.
+.Pp
+Examples:
+.D1 \&.Dd $\&Mdocdate$
+.D1 \&.Dd $\&Mdocdate: July 21 2007$
+.D1 \&.Dd July 21, 2007
+.Pp
+See also
+.Sx \&Dt
+and
+.Sx \&Os .
+.Ss \&Dl
+One-line intended display.
+This is formatted as literal text and is useful for commands and
+invocations.
+It is followed by a newline.
+.Pp
+Examples:
+.D1 \&.Dl % mandoc mdoc.7 | less
+.Pp
+See also
+.Sx \&Bd
+and
+.Sx \&D1 .
+.Ss \&Do
+Begins a block enclosed by double quotes.  Does not have any head
+arguments.
+.Pp
+Examples:
+.D1 \&.D1 \&Do April is the cruellest month \&Dc \e(em T.S. Eliot
+.Pp
+See also
+.Sx \&Dq .
+.Ss \&Dq
+Encloses its arguments in double quotes.
+.Pp
+Examples:
+.Bd -literal -offset indent -compact
+\&.Dq April is the cruellest month
+\e(em T.S. Eliot
+.Ed
+.Pp
+See also
+.Sx \&Do .
+.Ss \&Dt
+Document title.
+This is the mandatory second macro of any

 .Nm
 .Nm

-utility was written by 
-.An Kristaps Dzonsons Aq kristaps@kth.se .
-.\" SECTION
-.Sh CAVEATS
-There are several ambiguous parts of mdoc.
+file.
+Its calling syntax is as follows:
+.Pp
+.D1 \. Ns Sx \&Dt Op Cm title Op Cm section Op Cm volume | arch
+.Pp
+Its arguments are as follows:
+.Bl -tag -width Ds -offset Ds
+.It Cm title
+The document's title (name), defaulting to
+.Qq UNKNOWN
+if unspecified.
+It should be capitalised.
+.It Cm section
+The manual section.
+This may be one of
+.Ar 1
+.Pq utilities ,
+.Ar 2
+.Pq system calls ,
+.Ar 3
+.Pq libraries ,
+.Ar 3p
+.Pq Perl libraries ,
+.Ar 4
+.Pq devices ,
+.Ar 5
+.Pq file formats ,
+.Ar 6
+.Pq games ,
+.Ar 7
+.Pq miscellaneous ,
+.Ar 8
+.Pq system utilities ,
+.Ar 9
+.Pq kernel functions ,
+.Ar X11
+.Pq X Window System ,
+.Ar X11R6
+.Pq X Window System ,
+.Ar unass
+.Pq unassociated ,
+.Ar local
+.Pq local system ,
+.Ar draft
+.Pq draft manual ,
+or
+.Ar paper
+.Pq paper .
+It should correspond to the manual's filename suffix and defaults to
+.Qq 1
+if unspecified.
+.It Cm volume
+This overrides the volume inferred from
+.Ar section .
+This field is optional, and if specified, must be one of
+.Ar USD
+.Pq users' supplementary documents ,
+.Ar PS1
+.Pq programmers' supplementary documents ,
+.Ar AMD
+.Pq administrators' supplementary documents ,
+.Ar SMM
+.Pq system managers' manuals ,
+.Ar URM
+.Pq users' reference manuals ,
+.Ar PRM
+.Pq programmers' reference manuals ,
+.Ar KM
+.Pq kernel manuals ,
+.Ar IND
+.Pq master index ,
+.Ar MMI
+.Pq master index ,
+.Ar LOCAL
+.Pq local manuals ,
+.Ar LOC
+.Pq local manuals ,
+or
+.Ar CON
+.Pq contributed manuals .
+.It Cm arch
+This specifies a specific relevant architecture.
+If
+.Cm volume
+is not provided, it may be used in its place, else it may be used
+subsequent that.
+It, too, is optional.
+It must be one of
+.Ar alpha ,
+.Ar amd64 ,
+.Ar amiga ,
+.Ar arc ,
+.Ar arm ,
+.Ar armish ,
+.Ar aviion ,
+.Ar hp300 ,
+.Ar hppa ,
+.Ar hppa64 ,
+.Ar i386 ,
+.Ar landisk ,
+.Ar loongson ,
+.Ar luna88k ,
+.Ar mac68k ,
+.Ar macppc ,
+.Ar mvme68k ,
+.Ar mvme88k ,
+.Ar mvmeppc ,
+.Ar pmax ,
+.Ar sgi ,
+.Ar socppc ,
+.Ar sparc ,
+.Ar sparc64 ,
+.Ar sun3 ,
+.Ar vax ,
+or
+.Ar zaurus .
+.El
+.Pp
+Examples:
+.D1 \&.Dt FOO 1
+.D1 \&.Dt FOO 4 KM
+.D1 \&.Dt FOO 9 i386
+.Pp
+See also
+.Sx \&Dd
+and
+.Sx \&Os .
+.Ss \&Dv
+Defined variables such as preprocessor constants.
+.Pp
+Examples:
+.D1 \&.Dv BUFSIZ
+.D1 \&.Dv STDOUT_FILENO
+.Pp
+See also
+.Sx \&Er .
+.Ss \&Dx
+Format the DragonFly BSD version provided as an argument, or a default
+value if no argument is provided.
+.Pp
+Examples:
+.D1 \&.Dx 2.4.1
+.D1 \&.Dx
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+.Sx \&Ox ,
+and
+.Sx \&Ux .
+.Ss \&Ec
+.Ss \&Ed
+.Ss \&Ef
+.Ss \&Ek
+.Ss \&El
+.Ss \&Em
+Denotes text that should be emphasised.
+Note that this is a presentation term and should not be used for
+stylistically decorating technical terms.
+.Pp
+Examples:
+.D1 \&.Em Warnings!
+.D1 \&.Em Remarks :
+.Ss \&En
+.Ss \&Eo
+.Ss \&Er
+Display error constants.
+.Pp
+Examples:
+.D1 \&.Er EPERM
+.D1 \&.Er ENOENT
+.Pp
+See also
+.Sx \&Dv .
+.Ss \&Es
+.Ss \&Ev
+Environmental variables such as those specified in
+.Xr environ 7 .
+.Pp
+Examples:
+.D1 \&.Ev DISPLAY
+.D1 \&.Ev PATH
+.Ss \&Ex
+Inserts text regarding a utility's exit values.
+This macro must have first the
+.Fl std
+argument specified, then an optional
+.Ar utility .
+If
+.Ar utility
+is not provided, the document's name as stipulated in
+.Sx \&Nm
+is provided.
+.Ss \&Fa
+.Ss \&Fc
+.Ss \&Fd
+.Ss \&Fl
+Command-line flag.
+Used when listing arguments to command-line utilities.
+Prints a fixed-width hyphen
+.Sq \-
+directly followed by each argument.
+If no arguments are provided, a hyphen is printed followed by a space.
+If the argument is a macro, a hyphen is prefixed to the subsequent macro
+output.
+.Pp
+Examples:
+.D1 \&.Fl a b c
+.D1 \&.Fl \&Pf a b
+.D1 \&.Fl
+.D1 \&.Op \&Fl o \&Ns \&Ar file
+.Pp
+See also
+.Sx \&Cm .
+.Ss \&Fn
+.Ss \&Fo
+.Ss \&Fr
+.Ss \&Ft
+.Ss \&Fx
+Format the FreeBSD version provided as an argument, or a default value
+if no argument is provided.
+.Pp
+Examples:
+.D1 \&.Fx 7.1
+.D1 \&.Fx
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Nx ,
+.Sx \&Ox ,
+and
+.Sx \&Ux .
+.Ss \&Hf
+.Ss \&Ic
+.Ss \&In
+.Ss \&It
+.Ss \&Lb
+Specify a library.
+The calling syntax is as follows:
+.Pp
+.D1 \. Ns Sx \&Lb Cm library
+.Pp
+The
+.Cm library
+parameter may be a system library, such as
+.Cm libz
+or
+.Cm libpam ,
+in which case a small library description is printed next to the linker
+invocation; or a custom library, in which case the library name is
+printed in quotes.
+This is most commonly used in the
+.Em SYNOPSIS
+section as described in
+.Sx MANUAL STRUCTURE .
+.Pp
+Examples:
+.D1 \&.Lb libz
+.D1 \&.Lb mdoc
+.Ss \&Li
+.Ss \&Lk
+Format a hyperlink.
+The calling syntax is as follows:
+.Pp
+.D1 \. Ns Sx \&Lk Cm uri Op Cm name
+.Pp
+Examples:
+.D1 \&.Lk http://bsd.lv "The BSD.lv Project"
+.D1 \&.Lk http://bsd.lv
+.Pp
+See also
+.Sx \&Mt .
+.Ss \&Lp
+.Ss \&Ms
+.Ss \&Mt
+.Ss \&Nd
+.Ss \&Nm
+.Ss \&No
+.Ss \&Ns
+.Ss \&Nx
+Format the NetBSD version provided as an argument, or a default value if
+no argument is provided.
+.Pp
+Examples:
+.D1 \&.Nx 5.01
+.D1 \&.Nx
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Ox ,
+and
+.Sx \&Ux .
+.Ss \&Oc
+.Ss \&Oo
+.Ss \&Op
+.Ss \&Os
+Document operating system version.
+This is the mandatory third macro of
+any
+.Nm
+file.  Its calling syntax is as follows:
+.Pp
+.D1 \. Ns Sx \&Os Op Cm system
+.Pp
+The optional
+.Cm system
+parameter specifies the relevant operating system or environment.
+Left unspecified, it defaults to the local operating system version.
+This is the suggested form.
+.Pp
+Examples:
+.D1 \&.Os
+.D1 \&.Os KTH/CSC/TCS
+.D1 \&.Os BSD 4.3
+.Pp
+See also
+.Sx \&Dd
+and
+.Sx \&Dt .
+.Ss \&Ot
+Unknown usage.
+.Pp
+.Em Remarks :
+this macro has been deprecated.
+.Ss \&Ox
+Format the OpenBSD version provided as an argument, or a default value
+if no argument is provided.
+.Pp
+Examples:
+.D1 \&.Ox 4.5
+.D1 \&.Ox
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+and
+.Sx \&Ux .
+.Ss \&Pa
+.Ss \&Pc
+.Ss \&Pf
+.Ss \&Po
+.Ss \&Pp
+.Ss \&Pq
+.Ss \&Qc
+.Ss \&Ql
+.Ss \&Qo
+.Ss \&Qq
+.Ss \&Re
+Closes a
+.Sx \&Rs
+block.
+Does not have any tail arguments.
+.Ss \&Rs
+Begins a bibliographic
+.Pq Dq reference
+block.
+Does not have any head arguments.
+The block macro may only contain
+.Sx \&%A ,
+.Sx \&%B ,
+.Sx \&%C ,
+.Sx \&%D ,
+.Sx \&%I ,
+.Sx \&%J ,
+.Sx \&%N ,
+.Sx \&%O ,
+.Sx \&%P ,
+.Sx \&%Q ,
+.Sx \&%R ,
+.Sx \&%T ,
+and
+.Sx \&%V
+child macros (at least one must be specified).
+.Pp
+Examples:
+.Bd -literal -offset indent -compact
+\&.Rs
+\&.%A J. E. Hopcroft
+\&.%A J. D. Ullman
+\&.%B Introduction to Automata Theory, Languages, and Computation
+\&.%I Addison-Wesley
+\&.%C Reading, Massachusettes
+\&.%D 1979
+\&.Re
+.Ed
+.Pp
+If an
+.Sx \&Rs
+block is used within a SEE ALSO section, a vertical space is asserted
+before the rendered output, else the block continues on the current
+line.
+.Ss \&Rv
+.Ss \&Sc
+.Ss \&Sh
+.Ss \&Sm
+.Ss \&So
+.Ss \&Sq
+.Ss \&Ss
+.Ss \&St
+.Ss \&Sx
+.Ss \&Sy
+.Ss \&Tn
+.Ss \&Ud
+Prints out
+.Dq currently under development.
+.Ss \&Ux
+Format the UNIX name.
+Accepts no argument.
+.Pp
+Examples:
+.D1 \&.Ux
+.Pp
+See also
+.Sx \&At ,
+.Sx \&Bsx ,
+.Sx \&Bx ,
+.Sx \&Dx ,
+.Sx \&Fx ,
+.Sx \&Nx ,
+and
+.Sx \&Ox .
+.Ss \&Va
+.Ss \&Vt
+A variable type.
+This is also used for indicating global variables in the SYNOPSIS
+section, in which case a variable name is also specified.
+Note that it accepts
+.Sx Block partial-implicit
+syntax when invoked as the first macro in the SYNOPSIS section, else it
+accepts ordinary
+.Sx In-line
+syntax.
+.Pp
+Note that this should not be confused with
+.Sx \&Ft ,
+which is used for function return types.
+.Pp
+Examples:
+.D1 \&.Vt unsigned char
+.D1 \&.Vt extern const char * const sys_signame[] ;
+.Pp
+See also
+.Sx \&Ft
+and
+.Sx \&Va .
+.Ss \&Xc
+Close a scope opened by
+.Sx \&Xo .
+.Ss \&Xo
+Open an extension scope.
+This macro originally existed to extend the 9-argument limit of troff;
+since this limit has been lifted, the macro has been deprecated.
+.Ss \&Xr
+Link to another manual
+.Pq Qq cross-reference .
+Its calling syntax is
+.Pp
+.D1 \. Ns Sx \&Xr Cm name section
+.Pp
+The
+.Cm name
+and
+.Cm section
+are the name and section of the linked manual.
+If
+.Cm section
+is followed by non-punctuation, an
+.Sx \&Ns
+is inserted into the token stream.
+This behaviour is for compatibility with
+.Xr groff 1 .
+.Pp
+Examples:
+.D1 \&.Xr mandoc 1
+.D1 \&.Xr mandoc 1 ;
+.D1 \&.Xr mandoc 1 \&Ns s behaviour
+.Ss \&br
+.Ss \&sp
+.Sh COMPATIBILITY
+This section documents compatibility between mandoc and other other
+troff implementations, at this time limited to GNU troff
+.Pq Qq groff .
+The term
+.Qq historic groff
+refers to groff versions before the
+.Pa doc.tmac
+file re-write
+.Pq somewhere between 1.15 and 1.19 .
+.Pp
+Heirloom troff, the other significant troff implementation accepting
+\-mdoc, is similar to historic groff.

 .Pp
 .Bl -dash -compact
 .Pp
 .Bl -dash -compact

-.\" LIST-ITEM

 .It
 .It

-.Sq \&.Fa
-should be 
-.Sq \&.Va
-as function arguments are variables.
-.\" LIST-ITEM
+The comment syntax
+.Sq \e."
+is no longer accepted.
+.It
+In groff, the
+.Sx \&Pa
+macro does not format its arguments when used in the FILES section under
+certain list types.
+mandoc does.

 .It
 .It

-.Sq \&.Ft
-should be
-.Sq \&.Vt
-as function return types are still types.  Furthermore, the
-.Sq \&.Ft
-should be removed and
-.Sq \&.Fo ,
-which ostensibly follows it, should follow the same convention as
-.Sq \&.Va .
-.\" LIST-ITEM
+Historic groff does not print a dash for empty
+.Sx \&Fl
+arguments.
+mandoc and newer groff implementations do.

 .It
 .It

-.Sq \&.Va
-should formalise that only one or two arguments are acceptable: a
-variable name and optional, preceding type.
-.\" LIST-ITEM
+groff behaves irregularly when specifying
+.Sq \ef
+.Sx Text Decoration
+within line-macro scopes.
+mandoc follows a consistent system.

 .It
 .It

-.Sq \&.Fd
-is ambiguous.  It's commonly used to indicate an include file in the
-synopsis section.  
-.Sq \&.In
-should be used, instead.
-.\" LIST-ITEM
+In mandoc, negative scaling units are truncated to zero; groff would
+move to prior lines.
+Furthermore, the
+.Sq f
+scaling unit, while accepted, is rendered as the default unit.

 .It
 .It

-Only the
-.Sq \-literal
-argument to
-.Sq \&.Bd
-makes sense.  The remaining ones should be removed.
-.\" LIST-ITEM
+In quoted literals, groff allowed pair-wise double-quotes to produce a
+standalone double-quote in formatted output.
+This idiosyncratic behaviour is not applicable in mandoc.

 .It
 .It

-The 
-.Sq \&.Xo
+Display types
+.Sx \&Bd
+.Fl center

 and
 and

-.Sq \&.Xc
-macros should be deprecated.
-.\" LIST-ITEM
+.Fl right
+are aliases for
+.Fl left
+in manodc.  Furthermore, the
+.Fl file Ar file
+argument is ignored.
+Lastly, since text is not right-justified in mandoc (or even groff),
+.Fl ragged
+and
+.Fl filled
+are aliases, as are
+.Fl literal
+and
+.Fl unfilled .

 .It
 .It

-The
-.Sq \&.Dt
-macro lacks clarity.  It should be absolutely clear which title will
-render when formatting the manual page.
-.\" LIST-ITEM
+Historic groff has many un-callable macros.
+Most of these (excluding some block-level macros) are now callable.
+.It
+The vertical bar
+.Sq \(ba
+made historic groff
+.Qq go orbital
+but has been a proper delimiter since then.
+.It
+.Sx \&It Fl nested
+is assumed for all lists (it wasn't in historic groff): any list may be
+nested and
+.Fl enum
+lists will restart the sequence only for the sub-list.
+.It
+Some manuals use
+.Sx \&Li
+incorrectly by following it with a reserved character and expecting the
+delimiter to render.
+This is not supported in mandoc.

 .It
 .It

-A
-.Sq \&.Lx
-should be provided for Linux (\(`a la 
-.Sq \&.Ox ,
-.Sq \&.Nx 
-etc.).
-.\" LIST-ITEM
+In groff, the
+.Sx \&Fo
+macro only produces the first parameter.
+This is not the case in mandoc.

 .It
 .It

-There's no way to refer to references in
-.Sq \&.Rs/.Re
-blocks.
+In groff, the
+.Sx \&Cd ,
+.Sx \&Er ,
+.Sx \&Ex ,
+and
+.Sx \&Rv
+macros were stipulated only to occur in certain manual sections.
+mandoc does not have these restrictions.
+.It
+Newer groff and mandoc print
+.Qq AT&T UNIX
+prior to unknown arguments of
+.Sx \&At ;
+older groff did nothing.

 .El
 .El

+.Sh SEE ALSO
+.Xr mandoc 1 ,
+.Xr mandoc_char 7
+.Sh AUTHORS
+The
+.Nm
+reference was written by
+.An Kristaps Dzonsons Aq kristaps@bsd.lv .
+.\"
+.\" XXX: this really isn't the place for these caveats.
+.\" .
+.\" .
+.\" .Sh CAVEATS
+.\" There are many ambiguous parts of mdoc.
+.\" .
+.\" .Pp
+.\" .Bl -dash -compact
+.\" .It
+.\" .Sq \&Fa
+.\" should be
+.\" .Sq \&Va
+.\" as function arguments are variables.
+.\" .It
+.\" .Sq \&Ft
+.\" should be
+.\" .Sq \&Vt
+.\" as function return types are still types.  Furthermore, the
+.\" .Sq \&Ft
+.\" should be removed and
+.\" .Sq \&Fo ,
+.\" which ostensibly follows it, should follow the same convention as
+.\" .Sq \&Va .
+.\" .It
+.\" .Sq \&Va
+.\" should formalise that only one or two arguments are acceptable: a
+.\" variable name and optional, preceding type.
+.\" .It
+.\" .Sq \&Fd
+.\" is ambiguous.  It's commonly used to indicate an include file in the
+.\" synopsis section.
+.\" .Sq \&In
+.\" should be used, instead.
+.\" .It
+.\" Only the
+.\" .Sq \-literal
+.\" argument to
+.\" .Sq \&Bd
+.\" makes sense.  The remaining ones should be removed.
+.\" .It
+.\" The
+.\" .Sq \&Xo
+.\" and
+.\" .Sq \&Xc
+.\" macros should be deprecated.
+.\" .It
+.\" The
+.\" .Sq \&Dt
+.\" macro lacks clarity.  It should be absolutely clear which title will
+.\" render when formatting the manual page.
+.\" .It
+.\" A
+.\" .Sq \&Lx
+.\" should be provided for Linux (\(`a la
+.\" .Sq \&Ox ,
+.\" .Sq \&Nx
+.\" etc.).
+.\" .It
+.\" There's no way to refer to references in
+.\" .Sq \&Rs/Re
+.\" blocks.
+.\" .It
+.\" The \-split and \-nosplit dictates via
+.\" .Sq \&An
+.\" are re-set when entering and leaving the AUTHORS section.
+.\" .El
+.\" .