Added mandoc_a2time() for proper date conversion.

[mandoc.git] / man.7

diff --git a/man.7 b/man.7
index fe2b2b8fa8cb76cace994fd868da154e1a8d19e7..c3b313a9b7297800ceca96ac7579f846ac4925f3 100644 (file)
--- a/man.7
+++ b/man.7
@@ -1,4 +1,4 @@
-.\"    $Id: man.7,v 1.18 2009/07/04 09:00:41 kristaps Exp $
+.\"    $Id: man.7,v 1.43 2009/11/02 06:22:45 kristaps Exp $

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


@@ -14,34 +14,39 @@
 .\" 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: July 4 2009 $
+.Dd $Mdocdate: November 2 2009 $

 .Dt MAN 7
 .Os
 .Dt MAN 7
 .Os

-.\" SECTION
+.
+.

 .Sh NAME
 .Nm man
 .Nd man language reference
 .Sh NAME
 .Nm man
 .Nd man language reference

-.\" SECTION
+.
+.

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

-language was historically used to format 
+language was historically used to format

 .Ux
 .Ux

-manuals.  This reference document describes the syntax and structure of
-this language.
+manuals.  This reference document describes its syntax, structure, and
+usage.
+.

 .Pp
 .Pp

-.Em \&Do not
-use 
+.Bf -emphasis
+Do not use

 .Nm
 .Nm

-to write your manuals.  Use the
+to write your manuals.
+.Ef
+Use the

 .Xr mdoc 7
 language, instead.
 .Xr mdoc 7
 language, instead.

-.\" PARAGRAPH
+.

 .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:


@@ -49,21 +54,19 @@ prior macros:
 \&.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
 .Nm
 documents may contain only graphable 7-bit ASCII characters, the
 .Sh INPUT ENCODING
 .Nm
 documents may contain only graphable 7-bit ASCII characters, the

-space character
-.Sq \  ,
-and tabs
-.Sq \et . 
-All manuals must have
+space character, and the tabs character.  All manuals must have

 .Ux
 .Ux

-.Sq \en
-line termination.  
+line termination.
+.

 .Pp
 Blank lines are acceptable; where found, the output will assert a
 vertical space.
 .Pp
 Blank lines are acceptable; where found, the output will assert a
 vertical space.

+.

 .Pp
 The
 .Sq \ec
 .Pp
 The
 .Sq \ec


@@ -71,174 +74,663 @@ escape is common in historical
 .Nm
 documents; if encountered at the end of a word, it ensures that the
 subsequent word isn't off-set by whitespace.
 .Nm
 documents; if encountered at the end of a word, it ensures that the
 subsequent word isn't off-set by whitespace.

-.\" SUB-SECTION
+.
+.

 .Ss Comments
 .Ss Comments

-Anything following a
-.Sq \e" 
-delimiter is considered a comment (unless the 
-.Sq \e
-itself has been escaped) and is ignored to the end of line.
-Furthermore, a macro line with only a control character
-.Sq \. ,
-optionally followed by whitespace, is ignored.
-.\" SUB-SECTION
+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 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 \&] ) ;
 .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.
-.Pp
-Characters may alternatively be escaped by a slash-asterisk,
-.Sq \e* ,
-with the same combinations as described above.
-.Pp
-Terms may also be text-decorated using the
+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
 .Sq \ef

-escape followed by a text-decoration letter: B (bold), I, (italic), or P
-and R (Roman, or reset).
-.\" SUB-SECTION
+escape followed by an indicator: B (bold), I, (italic), or P and R
+(Roman, or reset).
+.
+.

 .Ss Whitespace
 Unless specifically escaped, consecutive blocks of whitespace are pruned
 from input.  These are later re-added, if applicable, by a front-end
 utility such as
 .Xr mandoc 1 .
 .Ss Whitespace
 Unless specifically escaped, consecutive blocks of whitespace are pruned
 from input.  These are later re-added, if applicable, by a front-end
 utility such as
 .Xr mandoc 1 .

-.\" SECTION
-.Sh STRUCTURE
+.
+.Ss Dates
+The
+.Sx \&TH
+macro is the only
+.Nm
+macro that requires a date.  The form for this date is the ISO-8601
+standard
+.Cm YYYY-MM-DD .
+.
+.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
+.
+.
+.Ss Scaling Widths
+Many macros support scaled widths for their arguments, such as
+stipulating a two-inch paragraph indentation with the following:
+.Bd -literal -offset indent
+\&.HP 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
+.Pp
+Using anything other than
+.Sq m ,
+.Sq n ,
+.Sq u ,
+or
+.Sq v
+is necessarily non-portable across output media.  See 
+.Sx COMPATIBILITY .
+.
+.Pp
+If a scaling unit is not provided, the numerical value is interpreted
+under the default rules of
+.Sq v
+for vertical spaces and
+.Sq u
+for horizontal ones.
+.Em Note :
+this differs from
+.Xr mdoc 7 ,
+which, if a unit is not provided, will instead interpret the string as
+literal text.
+.
+.
+.Sh MANUAL STRUCTURE

 Each
 .Nm
 document must contain contains at least the
 Each
 .Nm
 document must contain contains at least the

-.Sq \&.TH
+.Sx \&TH

 macro describing the document's section and title.  It may occur
 anywhere in the document, although conventionally, it appears as the
 first macro.
 macro describing the document's section and title.  It may occur
 anywhere in the document, although conventionally, it appears as the
 first macro.

+.

 .Pp
 .Pp

-Beyond the 
-.Sq \&.TH ,
-at least one macro or text node must appear in the document.
-.\" SECTION
-.Sh SYNTAX
+Beyond
+.Sx \&TH ,
+at least one macro or text node must appear in the document.  Documents
+are generally structured as follows:
+.Bd -literal -offset indent
+\&.TH FOO 1 2009-10-10
+\&.
+\&.SH NAME
+\efBfoo\efR \e(en a description goes here
+\&.\e\*q The next is for sections 2 & 3 only.
+\&.\e\*q .SH LIBRARY
+\&.
+\&.SH SYNOPSIS
+\efBfoo\efR [\efB\e-options\efR] arguments...
+\&.
+\&.SH DESCRIPTION
+The \efBfoo\efR utility processes files...
+\&.
+\&.\e\*q .SH IMPLEMENTATION NOTES
+\&.\e\*q The next is for sections 1 & 8 only.
+\&.\e\*q .SH EXIT STATUS
+\&.\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 .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 .BR foo ( 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
+.Pp
+The sections in a
+.Nm
+document are conventionally ordered as they appear above.  Sections
+should be composed as follows:
+.Bl -ohang -offset indent
+.It Em NAME
+The name(s) and a short description of the documented material.  The
+syntax for this is generally as follows:
+.Pp
+.D1 \efBname\efR \e(en description
+.It Em LIBRARY
+The name of the library containing the documented material, which is
+assumed to be a function in a section 2 or 3 manual.  For functions in
+the C library, this may be as follows:
+.Pp
+.D1 Standard C Library (libc, -lc)
+.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:
+.Pp
+.D1 \efBname\efR [-\efBab\efR] [-\efBc\efR\efIarg\efR] \efBpath\efR...
+.Pp
+For the second, function calls (sections 2, 3, 9):
+.Pp
+.D1 \. Ns Sx \&B No char *name(char *\efIarg\efR);
+.Pp
+And for the third, configurations (section 4):
+.Pp
+.D1 \. Ns Sx \&B No name* at cardbus ? function ?
+.Pp
+Manuals not in these sections generally don't need a 
+.Em SYNOPSIS .
+.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).
+.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 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.
+.
+.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.
+.
+.It Em ENVIRONMENT
+Documents any usages of environment variables, e.g.,
+.Xr environ 7 .
+.
+.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.).
+.
+.It Em EXAMPLES
+Example usages.  This often contains snippets of well-formed,
+well-tested invocations.  Make doubly sure that your examples work
+properly!  Assume that users will skip to this section and use your
+example verbatim.
+.
+.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.
+.
+.It Em ERRORS
+Documents error handling in sections 2, 3, and 9.
+.
+.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
+.D1 \. Ns Sx \&BR No bar \&( 1 \&),
+.D1 \. Ns Sx \&BR No foo \&( 1 \&),
+.D1 \. Ns Sx \&BR No baz \&( 2 \&).
+.
+.It Em STANDARDS
+References any standards implemented or used, such as
+.Pp
+.D1 IEEE Std 1003.2 (\e(lqPOSIX.2\e(rq)
+.Pp
+If not adhering to any standards, the
+.Em HISTORY
+section should be used.
+.
+.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.
+.
+.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
 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,
-.Sq \&.PP
-and
-.Sq \&.\ \ \ \&PP
-are equivalent.
-.Pp
-All 
-.Nm
-macros follow the same structural rules:
+sit between the control character and the macro name.  Thus, the
+following are equivalent:

 .Bd -literal -offset indent
 .Bd -literal -offset indent

-\&.YO \(lBbody...\(rB 
+\&.PP
+\&.\ \ \ PP

 .Ed
 .Ed

+.

 .Pp
 The
 .Pp
 The

-.Dq body
-consists of zero or more arguments to the macro.
-.Pp

 .Nm
 .Nm

-has a primitive notion of multi-line scope for the following macros: 
-.Sq \&.TM ,
-.Sq \&.SM ,
-.Sq \&.SB ,
-.Sq \&.BI ,
-.Sq \&.IB ,
-.Sq \&.BR ,
-.Sq \&.RB ,
-.Sq \&.R ,
-.Sq \&.B ,
-.Sq \&.I ,
-.Sq \&.IR 
-and
-.Sq \&.RI .
-When these macros are invoked without arguments, the subsequent line is
-considered a continuation of the macro.  Thus:
-.Bd -literal -offset indent 
-\&.RI 
+macros are classified by scope: line scope or block scope.  Line
+macros are only scoped to the current line (and, in some situations,
+the subsequent line).  Block macros are scoped to the current line and
+subsequent lines until closed by another block macro.
+.
+.
+.Ss Line Macros
+Line macros are generally scoped to the current line, with the body
+consisting of zero or more arguments.  If a macro is scoped to the next
+line and the line arguments are empty, the next line is used instead,
+else the general syntax is used.  Thus:
+.Bd -literal -offset indent
+\&.I

 foo
 .Ed
 foo
 .Ed

+.

 .Pp
 .Pp

-is equivalent to 
-.Sq \&.RI foo .
-If two consecutive lines exhibit the latter behaviour,
-an error is raised.  Thus, the following is not acceptable:
-.Bd -literal -offset indent 
-\&.RI 
-\&.I 
-Hello, world.
+is equivalent to
+.Sq \&.I foo .
+If next-line macros are invoked consecutively, only the last is used.
+If a next-line macro is proceded by a block macro, it is ignored.
+.Bd -literal -offset indent
+\&.YO \(lBbody...\(rB
+\(lBbody...\(rB

 .Ed
 .Ed

+.

 .Pp
 .Pp

-The
-.Sq \&.TP
-macro is similar, but does not need an empty argument line to trigger
-the behaviour.
-.\" SECTION
-.Sh MACROS
-This section contains a complete list of all 
-.Nm
-macros and corresponding number of arguments.
-.Pp
-.Bl -column "MacroX" "Arguments" -compact -offset indent
-.It Em Macro Ta Em Arguments
-.It \&.TH    Ta    >1, <6
-.It \&.SH    Ta    >0
-.It \&.SS    Ta    >0
-.It \&.TP    Ta    n
-.It \&.LP    Ta    0
-.It \&.PP    Ta    0
-.It \&.P     Ta    0
-.It \&.IP    Ta    <3
-.It \&.HP    Ta    <2
-.It \&.SM    Ta    n
-.It \&.SB    Ta    n
-.It \&.BI    Ta    n
-.It \&.IB    Ta    n
-.It \&.BR    Ta    n
-.It \&.RB    Ta    n
-.It \&.R     Ta    n
-.It \&.B     Ta    n
-.It \&.I     Ta    n
-.It \&.IR    Ta    n
-.It \&.RI    Ta    n
+.Bl -column -compact -offset indent "MacroX" "ArgumentsX" "ScopeXXXXX"
+.It Em Macro Ta Em Arguments Ta Em Scope
+.It Sx \&B   Ta    n         Ta    next-line
+.It Sx \&BI  Ta    n         Ta    current
+.It Sx \&BR  Ta    n         Ta    current
+.It Sx \&DT  Ta    0         Ta    current
+.It Sx \&I   Ta    n         Ta    next-line
+.It Sx \&IB  Ta    n         Ta    current
+.It Sx \&IR  Ta    n         Ta    current
+.It Sx \&PD  Ta    n         Ta    current
+.It Sx \&R   Ta    n         Ta    next-line
+.It Sx \&RB  Ta    n         Ta    current
+.It Sx \&RI  Ta    n         Ta    current
+.It Sx \&SB  Ta    n         Ta    next-line
+.It Sx \&SM  Ta    n         Ta    next-line
+.It Sx \&TH  Ta    >1, <6    Ta    current
+.It Sx \&UC  Ta    n         Ta    current
+.It Sx \&br  Ta    0         Ta    current
+.It Sx \&fi  Ta    0         Ta    current
+.It Sx \&i   Ta    n         Ta    current
+.It Sx \&na  Ta    0         Ta    current
+.It Sx \&nf  Ta    0         Ta    current
+.It Sx \&r   Ta    0         Ta    current
+.It Sx \&sp  Ta    1         Ta    current

 .El
 .El

+.

 .Pp
 .Pp

-Although not historically part of the
-.Nm
-system, the following macros are also supported:
+The
+.Sx \&PD ,
+.Sx \&RS ,
+.Sx \&RE ,
+.Sx \&UC ,
+.Sx \&br ,
+.Sx \&fi ,
+.Sx \&i ,
+.Sx \&na ,
+.Sx \&nf ,
+.Sx \&r ,
+and
+.Sx \&sp
+macros should not be used.  They're included for compatibility.
+.
+.
+.Ss Block Macros
+Block macros are comprised of a head and body.  Like for in-line macros,
+the head is scoped to the current line and, in one circumstance, the
+next line; the body is scoped to subsequent lines and is closed out by a
+subsequent block macro invocation.
+.Bd -literal -offset indent
+\&.YO \(lBhead...\(rB
+\(lBhead...\(rB
+\(lBbody...\(rB
+.Ed
+.
+.Pp
+The closure of body scope may be to the section, where a macro is closed
+by
+.Sx \&SH ;
+sub-section, closed by a section or
+.Sx \&SS ;
+part, closed by a section, sub-section, or
+.Sx \&RE ;
+or paragraph, closed by a section, sub-section, part, 
+.Sx \&HP ,
+.Sx \&IP ,
+.Sx \&LP ,
+.Sx \&P ,
+.Sx \&PP ,
+or
+.Sx \&TP .
+No closure refers to an explicit block closing macro.
+.

 .Pp
 .Pp

-.Bl -column "MacroX" "Arguments" -compact -offset indent
-.It Em Macro Ta Em Arguments
-.It \&.br    Ta    0
-.It \&.i     Ta    n
+.Bl -column "MacroX" "ArgumentsX" "Head ScopeX" "sub-sectionX" -compact -offset indent
+.It Em Macro Ta Em Arguments Ta Em Head Scope Ta Em Body Scope
+.It Sx \&HP  Ta    <2        Ta    current    Ta    paragraph
+.It Sx \&IP  Ta    <3        Ta    current    Ta    paragraph
+.It Sx \&LP  Ta    0         Ta    current    Ta    paragraph
+.It Sx \&P   Ta    0         Ta    current    Ta    paragraph
+.It Sx \&PP  Ta    0         Ta    current    Ta    paragraph
+.It Sx \&RE  Ta    0         Ta    current    Ta    none
+.It Sx \&RS  Ta    1         Ta    current    Ta    part
+.It Sx \&SH  Ta    >0        Ta    next-line  Ta    section
+.It Sx \&SS  Ta    >0        Ta    next-line  Ta    sub-section
+.It Sx \&TP  Ta    n         Ta    next-line  Ta    paragraph

 .El
 .El

+.

 .Pp
 .Pp

-These follow the same calling conventions as the above
-.Nm
-macros.
-.\" SECTION
+If a block macro is next-line scoped, it may only be followed by in-line
+macros (excluding
+.Sx \&DT ,
+.Sx \&PD ,
+.Sx \&TH ,
+.Sx \&UC ,
+.Sx \&br ,
+.Sx \&na ,
+.Sx \&sp ,
+.Sx \&nf ,
+and
+.Sx \&fi ) .
+.
+.
+.Sh REFERENCE
+This section is a canonical reference to all macros, arranged
+alphabetically.  For the scoping of individual macros, see
+.Sx MACRO SYNTAX .
+.
+.Ss \&B
+Text is rendered in bold face.
+.Ss \&BI
+Text is rendered alternately in bold face and italic.  Thus, 
+.Sq .BI this word and that
+causes
+.Sq this
+and
+.Sq and
+to render in bold face, while 
+.Sq word
+and
+.Sq that
+render in italics.  Whitespace between arguments is omitted in output.
+.Ss \&BR
+Text is rendered alternately in bold face and roman (the default font).
+Whitespace between arguments is omitted in output.
+.Ss \&DT
+Has no effect.  Included for compatibility.
+.Ss \&HP
+Begin a paragraph whose initial output line is left-justified, but
+subsequent output lines are indented, with the following syntax:
+.Bd -literal -offset indent
+\&.HP [width]
+.Ed
+.
+.Pp
+If scaling width
+.Va width
+is specified, it's saved for later paragraph left-margins; if
+unspecified, the saved or default width is used.
+.Ss \&I
+Text is rendered in italics.
+.Ss \&IB
+Text is rendered alternately in italics and bold face.  Whitespace
+between arguments is omitted in output.
+.Ss \&IP
+Begin a paragraph with the following syntax:
+.Bd -literal -offset indent
+\&.IP [head [width]]
+.Ed
+.
+.Pp
+This follows the behaviour of the
+.Sx \&TP
+except for the macro syntax (all arguments on the line, instead of
+having next-line scope).  If
+.Va width
+is specified, it's saved for later paragraph left-margins; if
+unspecified, the saved or default width is used.
+.Ss \&IR
+Text is rendered alternately in italics and roman (the default font).
+Whitespace between arguments is omitted in output.
+.Ss \&LP
+Begin an undecorated paragraph.  The scope of a paragraph is closed by a
+subsequent paragraph, sub-section, section, or end of file.  The saved
+paragraph left-margin width is re-set to the default.
+.Ss \&P
+Synonym for
+.Sx \&LP .
+.Ss \&PP
+Synonym for
+.Sx \&LP .
+.Ss \&R
+Text is rendered in roman (the default font).
+.Ss \&RB
+Text is rendered alternately in roman (the default font) and bold face.
+Whitespace between arguments is omitted in output.
+.Ss \&RE
+Explicitly close out the scope of a prior
+.Sx \&RS .
+.Ss \&RI
+Text is rendered alternately in roman (the default font) and italics.
+Whitespace between arguments is omitted in output.
+.Ss \&RS
+Begin a part setting the left margin.  The left margin controls the
+offset, following an initial indentation, to un-indented text such as
+that of
+.Sx \&PP .
+A scaling width may be specified as following:
+.Bd -literal -offset indent
+\&.RS [width]
+.Ed
+.
+.Pp
+If
+.Va width
+is not specified, the saved or default width is used. 
+.Ss \&SB
+Text is rendered in small size (one point smaller than the default font)
+bold face.
+.Ss \&SH
+Begin a section.  The scope of a section is only closed by another
+section or the end of file.  The paragraph left-margin width is re-set
+to the default.
+.Ss \&SM
+Text is rendered in small size (one point smaller than the default
+font).
+.Ss \&SS
+Begin a sub-section.  The scope of a sub-section is closed by a
+subsequent sub-section, section, or end of file.  The paragraph
+left-margin width is re-set to the default.
+.Ss \&TH
+Sets the title of the manual page with the following syntax:
+.Pp
+.D1 \. Ns Sx \&TH No Cm title msec Op Cm date Op Cm src Op Cm vol
+.Pp
+At least the upper-case document title
+.Cm title
+and numeric manual section
+.Cm msec
+arguments must be provided.  The
+.Cm date
+argument should be formatted as described in
+.Sx Dates :
+if it does not conform, the current date is used instead.  The
+.Cm src
+string specifies the organisation providing the utility.  The
+.Cm vol
+string replaces the default rendered volume, which is dictated by the
+manual section.
+.Pp
+Examples:
+.Bd -literal -offset indent
+\&.TH CVS 5 "1992-02-12" GNU
+.Ed
+.
+.Ss \&TP
+Begin a paragraph where the head, if exceeding the indentation width, is
+followed by a newline; if not, the body follows on the same line after a
+buffer to the indentation width.  Subsequent output lines are indented.
+.
+.Pp
+The indentation scaling width may be set as follows:
+.Bd -literal -offset indent
+\&.TP [width]
+.Ed
+.
+.Pp
+If
+.Va width
+is specified, it's saved for later paragraph left-margins; if
+unspecified, the saved or default width is used.
+.Ss \&PD
+Has no effect.  Included for compatibility.
+.Ss \&UC
+Has no effect.  Included for compatibility.
+.Ss \&br
+Breaks the current line.  Consecutive invocations have no further effect.
+.Ss \&fi
+End literal mode begun by
+.Sx \&nf .
+.Ss \&i
+Italicise arguments.  If no arguments are specified, all subsequent text
+is italicised.
+.Ss \&na
+Don't align to the right margin.
+.Ss \&nf
+Begin literal mode: all subsequent free-form lines have their end of
+line boundaries preserved.  May be ended by
+.Sx \&fi .
+.Ss \&r
+Fonts and styles (bold face, italics) reset to roman (default font).
+.Ss \&sp
+Insert n spaces, where n is the macro's positive numeric argument.  If
+0, this is equivalent to the
+.Sx \&br
+macro.
+.
+.

 .Sh COMPATIBILITY
 .Sh COMPATIBILITY

-See
-.Xr mdoc 7
-for groff compatibility notes.
-.\" SECTION
+This section documents compatibility with other roff implementations, at
+this time limited to
+.Xr groff 1 .
+.Bl -hyphen
+.It
+In quoted literals, groff allowed pair-wise double-quotes to produce a
+standalone double-quote in formatted output.  This idiosyncratic
+behaviour is no longer applicable.
+.It
+The
+.Sq sp
+macro does not accept negative numbers.
+.It
+Blocks of whitespace are stripped from both macro and free-form text
+lines (except when in literal mode), while groff would retain whitespace
+in free-form text lines.
+.El
+.
+.

 .Sh SEE ALSO
 .Xr mandoc 1 ,
 .Xr mandoc_char 7
 .Sh SEE ALSO
 .Xr mandoc 1 ,
 .Xr mandoc_char 7

-.\" SECTION
+.
+.

 .Sh AUTHORS
 The
 .Nm
 .Sh AUTHORS
 The
 .Nm

-utility was written by 
+reference was written by

 .An Kristaps Dzonsons Aq kristaps@kth.se .
 .An Kristaps Dzonsons Aq kristaps@kth.se .

-.\" SECTION
+.
+.

 .Sh CAVEATS
 Do not use this language.  Use
 .Xr mdoc 7 ,
 instead.
 .Sh CAVEATS
 Do not use this language.  Use
 .Xr mdoc 7 ,
 instead.

+.