-.\" $Id: man.7,v 1.77 2010/07/19 10:48:36 kristaps Exp $
+.\" $Id: man.7,v 1.105 2011/08/18 08:58:43 kristaps Exp $
.\"
-.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2009, 2010 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
.\" 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 19 2010 $
+.Dd $Mdocdate: August 18 2011 $
.Dt MAN 7
.Os
.Sh NAME
.Xr mdoc 7
language, instead.
.Pp
-An
+A
.Nm
document follows simple rules: lines beginning with the control
character
\&.SH Macro lines change control state.
Other lines are interpreted within the current state.
.Ed
-.Sh INPUT ENCODING
+.Sh LANGUAGE SYNTAX
.Nm
documents may contain only graphable 7-bit ASCII characters, the
-space character, and the tabs character.
-All manuals must have
-.Ux
-line termination.
-.Pp
-Blank lines are acceptable; where found, the output will assert a
-vertical space.
+space character, and the tab character.
+The back-space character
+.Sq \e
+indicates the start of an escape sequence for
+.Sx Comments ,
+.Sx Predefined Strings ,
+and
+.Sx Special Characters .
.Ss Comments
-Text following a
+Text following an escaped double-quote
.Sq \e\*q ,
-whether in a macro or free-form text line, is ignored to the end of
+whether in a macro or text line, is ignored to the end of
line.
-A macro line with only a control character and comment escape,
-.Sq \&.\e\*q ,
+A macro line beginning with a control character and comment escape
+.Sq \&.\e\*q
is also ignored.
-Macro lines with only a control character and optionally whitespace are
+Furthermore,
+macro lines with only a control character and optional trailing
+whitespace are
stripped from input.
+.Pp
+Examples:
+.Bd -literal -offset indent -compact
+\&.\e\*q This is a comment line.
+\&.\e\*q The next line is ignored:
+\&.
+\&.Em Emphasis \e\*q This is also a comment.
+.Ed
.Ss Special Characters
-Special characters may occur in both macro and free-form lines.
+Special characters are used to encode special glyphs and are rendered
+differently across output media.
+They may occur in both macro and text lines.
Sequences begin with the escape character
.Sq \e
followed by either an open-parenthesis
.Sq \&[
for n-character sequences (terminated at a close-bracket
.Sq \&] ) ;
-or a single one-character sequence.
+or a single one character sequence.
+.Pp
+Examples:
+.Bl -tag -width Ds -offset indent -compact
+.It \e(em
+em dash
+.It \ee
+backslash
+.El
+.Pp
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
+escape followed by an indicator: B (bold), I (italic), R (regular), or P
(revert to previous mode):
-.Pp
-.D1 \efBbold\efR \efIitalic\efP
-.Pp
-A numerical representation 3, 2, or 1 (bold, italic, and Roman,
+A numerical representation 3, 2, or 1 (bold, italic, and regular,
respectively) may be used instead.
A text decoration is only valid, if specified in free-form text, until
the next macro invocation; if specified within a macro, it's only valid
The
.Sq \ef
attribute is forgotten when entering or exiting a macro block.
+.Pp
+Examples:
+.Bl -tag -width Ds -offset indent -compact
+.It \efBbold\efR
+write in bold, then switch to regular
+.It \efIitalic\efP
+write in italic, then return to previous
+.El
+.Ss Predefined Strings
+Predefined strings, like
+.Sx Special Characters ,
+mark special output glyphs.
+Predefined strings are escaped with the slash-asterisk,
+.Sq \e* :
+single-character
+.Sq \e*X ,
+two-character
+.Sq \e*(XX ,
+and N-character
+.Sq \e*[N] .
+.Pp
+Examples:
+.Bl -tag -width Ds -offset indent -compact
+.It \e*(Am
+ampersand
+.It \e*(Ba
+vertical bar
+.El
+.Pp
+These strings are set using
+.Xr roff 7 ,
+although
+.Nm
+consists of several pre-set escapes listed in
+.Xr mandoc_char 7 .
.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 spaces, are permitted and
-rendered as an empty line.
-.Pp
+In text lines, whitespace is preserved within a line.
In macro lines, whitespace delimits arguments and is discarded.
-If arguments are quoted, whitespace within the quotes is retained.
-.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 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:]? ,
+Unescaped trailing spaces are stripped from text line input unless in a
+literal context.
+In general, trailing whitespace on any input line is discouraged for
+reasons of portability.
+In the rare case that a blank character is needed at the end of an
+input line, it may be forced by
+.Sq \e\ \e& .
+.Pp
+If the first character of a text line is a space, that line is printed
+with a leading newline.
+.Ss Quotation
+Macro arguments may be quoted with double-quotes; in this case,
+whitespace within the quotes is retained as part of the argument.
+.Pp
+A quoted argument begins with a double-quote preceded by whitespace.
+The next double-quote not pairwise adjacent to another double-quote
+terminates the literal, regardless of surrounding whitespace.
+.Pp
+In unquoted arguments, space characters can alternatively be included
+by preceding them with a backslash
+.Pq Sq \e\~ ,
+but quoting is usually better for clarity.
+.Pp
+Note that any quoted text, even if it would cause a macro invocation
+when unquoted, is considered literal text.
+.Pp
+In text lines, quotes are regarded as opaque text.
+.Ss Scaling Widths
+Many macros support scaled widths for their arguments.
+The syntax for a scaled width 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.
+.Pp
The following scaling units are accepted:
.Pp
.Bl -tag -width Ds -offset indent -compact
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
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.
+.Pp
+Examples:
+.Bl -tag -width Ds -offset indent -compact
+.It \&.HP 2i
+two-inch tagged list indentation
+.Pq see Sx \&HP
+.It \&.sp 2v
+two vertical spaces
+.Pq see Sx \&sp
+.El
.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
+Sentences should terminate at the end of an input line.
+By doing this, a formatter 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 \&) ,
+delimiters
+.Po
+.Sq \&) ,
.Sq \&] ,
.Sq \&' ,
-.Sq \&" ) .
+.Sq \&"
+.Pc .
+.Pp
+Examples:
+.Bd -literal -offset indent -compact
+Do not end sentences mid-line like this. Instead,
+end a sentence like this.
+A new sentence gets a new line.
+.Ed
.Sh MANUAL STRUCTURE
Each
.Nm
-document must contain contains at least the
+document must contain the
.Sx \&TH
macro describing the document's section and title.
-It may occur anywhere in the document, although conventionally, it
+It may occur anywhere in the document, although conventionally it
appears as the first macro.
.Pp
Beyond
.Sx \&TH ,
at least one macro or text node must appear in the document.
-Documents are generally structured as follows:
+.Pp
+The following is a well-formed skeleton
+.Nm
+file for a utility
+.Qq progname :
.Bd -literal -offset indent
-\&.TH FOO 1 2009-10-10
+\&.TH PROGNAME 1 2009-10-10
\&.SH NAME
-\efBfoo\efR \e(en a description goes here
-\&.\e\*q The next is for sections 2 & 3 only.
+\efBprogname\efR \e(en a description goes here
\&.\e\*q .SH LIBRARY
+\&.\e\*q For sections 2 & 3 only.
+\&.\e\*q Not used in OpenBSD.
\&.SH SYNOPSIS
-\efBfoo\efR [\efB\e-options\efR] arguments...
+\efBprogname\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 2, 3, & 9 only.
+\&.\e\*q Not used in OpenBSD.
\&.\e\*q .SH RETURN VALUES
-\&.\e\*q The next is for sections 1, 6, 7, & 8 only.
+\&.\e\*q For sections 2, 3, & 9 only.
\&.\e\*q .SH ENVIRONMENT
+\&.\e\*q For sections 1, 6, 7, & 8 only.
\&.\e\*q .SH FILES
-\&.\e\*q The next is for sections 1 & 8 only.
\&.\e\*q .SH EXIT STATUS
+\&.\e\*q For sections 1, 6, & 8 only.
\&.\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 For sections 1, 4, 6, 7, & 8 only.
\&.\e\*q .SH ERRORS
+\&.\e\*q For sections 2, 3, & 9 only.
\&.\e\*q .SH SEE ALSO
\&.\e\*q .BR foo ( 1 )
\&.\e\*q .SH STANDARDS
\&.\e\*q .SH CAVEATS
\&.\e\*q .SH BUGS
\&.\e\*q .SH SECURITY CONSIDERATIONS
+\&.\e\*q Not used in OpenBSD.
.Ed
.Pp
The sections in a
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.
+This section 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
+It's helpful to document both the file name and a short description of how
the file is used (created, modified, etc.).
.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.
+This section documents the command exit status for
+section 1, 6, and 8 utilities.
Historically, this information was described in
.Em DIAGNOSTICS ,
a practise that is now discouraged.
Example usages.
This often contains snippets of well-formed,
well-tested invocations.
-Make doubly sure that your examples work properly!
+Make sure that examples work properly!
.It Em DIAGNOSTICS
Documents error conditions.
This is most useful in section 4 manuals.
.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.
+A brief history of the subject, including where support first appeared.
.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.
+Credits to the person or persons who wrote the code and/or documentation.
+Authors should generally be noted by both name and email address.
.It Em CAVEATS
-Explanations of common misuses and misunderstandings should be explained
+Common misuses and misunderstandings should be explained
in this section.
.It Em BUGS
-Extant bugs should be described in this section.
+Known bugs, limitations, and work-arounds 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 ,
+Macros are one to three characters in length and begin with a
+control character,
.Sq \&. ,
at the beginning of the line.
The
\&.\ \ \ PP
.Ed
.Pp
+To include space characters in macro arguments, arguments may be quoted;
+see the
+.Sq MACRO SYNTAX
+section in the
+.Xr roff 7
+manual for details.
+.Pp
The
.Nm
macros are classified by scope: line scope or block scope.
.Sq \&.I foo .
If next-line macros are invoked consecutively, only the last is used.
If a next-line macro is followed by a non-next-line macro, an error is
-raised (unless in the case of
+raised, except for
.Sx \&br ,
.Sx \&sp ,
-or
-.Sx \&na ) .
+and
+.Sx \&na .
.Pp
The syntax is as follows:
.Bd -literal -offset indent
.It Sx \&I Ta n Ta next-line Ta \&
.It Sx \&IB Ta n Ta current Ta \&
.It Sx \&IR Ta n Ta current Ta \&
-.\" .It Sx \&PD Ta n Ta current Ta compat
.It Sx \&R Ta n Ta next-line Ta \&
.It Sx \&RB Ta n Ta current Ta \&
.It Sx \&RI Ta n Ta current Ta \&
.It Sx \&UC Ta <=1 Ta current Ta \&
.It Sx \&br Ta 0 Ta current Ta compat
.It Sx \&fi Ta 0 Ta current Ta compat
-.It Sx \&i Ta n Ta current Ta compat
+.It Sx \&ft Ta 1 Ta current Ta compat
+.It Sx \&in Ta 1 Ta current Ta compat
.It Sx \&na Ta 0 Ta current Ta compat
.It Sx \&nf Ta 0 Ta current Ta compat
-.It Sx \&r Ta 0 Ta current Ta compat
.It Sx \&sp Ta 1 Ta current Ta compat
-.\" .It Sx \&Sp Ta <1 Ta current Ta compat
-.\" .It Sx \&Vb Ta <1 Ta current Ta compat
-.\" .It Sx \&Ve Ta 0 Ta current Ta compat
.El
.Pp
Macros marked as
.Nm
manuals.
.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
+Block macros comprise a head and body.
+As with in-line macros, the head is scoped to the current line and, in
one circumstance, the next line (the next-line stipulations as in
.Sx Line Macros
apply here as well).
Text is rendered in bold face.
.Pp
See also
-.Sx \&I ,
-.Sx \&R ,
-.Sx \&b ,
-.Sx \&i ,
+.Sx \&I
and
-.Sx \&r .
+.Sx \&R .
.Ss \&BI
Text is rendered alternately in bold face and italic.
Thus,
.Pp
Examples:
.Pp
-.D1 \&.BI bold italic bold italic
+.Dl \&.BI bold italic bold italic
.Pp
The output of this example will be emboldened
.Dq bold
Text is rendered in italics.
.Pp
See also
-.Sx \&B ,
-.Sx \&R ,
-.Sx \&b ,
-.Sx \&i ,
+.Sx \&B
and
-.Sx \&r .
+.Sx \&R .
.Ss \&IB
-Text is rendered alternately in italics and bold face. Whitespace
-between arguments is omitted in output.
+Text is rendered alternately in italics and bold face.
+Whitespace between arguments is omitted in output.
.Pp
See
.Sx \&BI
The
.Cm width
argument defines the width of the left margin and is defined by
-.Sx Scaling Widths ,
+.Sx Scaling Widths .
It's saved for later paragraph left-margins; if unspecified, the saved or
default width is used.
.Pp
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.
+The saved paragraph left-margin width is reset to the default.
.Pp
See also
.Sx \&HP ,
Text is rendered in roman (the default font).
.Pp
See also
-.Sx \&I ,
-.Sx \&B ,
-.Sx \&b ,
-.Sx \&i ,
+.Sx \&I
and
-.Sx \&r .
+.Sx \&B .
.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 .
+The default left margin is restored to the state of the original
+.Sx \&RS
+invocation.
.Ss \&RI
Text is rendered alternately in roman (the default font) and italics.
Whitespace between arguments is omitted in output.
and
.Sx \&IR .
.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 .
+Temporarily reset the default left margin.
This has the following syntax:
.Bd -filled -offset indent
-.Pf \. Sx \&Rs
+.Pf \. Sx \&RS
.Op Cm width
.Ed
.Pp
argument must conform to
.Sx Scaling Widths .
If not specified, the saved or default width is used.
+.Pp
+See also
+.Sx \&RE .
.Ss \&SB
Text is rendered in small size (one point smaller than the default font)
bold face.
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.
+The paragraph left-margin width is reset to the default.
.Ss \&SM
Text is rendered in small size (one point smaller than the default
font).
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.
+The paragraph left-margin width is reset to the default.
.Ss \&TH
Sets the title of the manual page with the following syntax:
.Bd -filled -offset indent
.Pf \. Sx \&TH
-.Cm title section
-.Op Cm date Op Cm source Op Cm volume
+.Ar title section date
+.Op Ar source Op Ar volume
.Ed
.Pp
-At least the upper-case document title
-.Cm title
-and numeric manual section
-.Cm section
-arguments must be provided.
-The
-.Cm date
-argument should be formatted as described in
-.Sx Dates ,
-but will be printed verbatim if it is not.
-If the date is not specified, the current date is used.
-The
-.Cm source
+Conventionally, the document
+.Ar title
+is given in all caps.
+The recommended
+.Ar date
+format is
+.Sy YYYY-MM-DD
+as specified in the ISO-8601 standard;
+if the argument does not conform, it is printed verbatim.
+If the
+.Ar date
+is empty or not specified, the current date is used.
+The optional
+.Ar source
string specifies the organisation providing the utility.
The
-.Cm volume
+.Ar volume
string replaces the default rendered volume, which is dictated by the
manual section.
.Pp
Examples:
.Pp
-.D1 \&.TH CVS 5 "1992-02-12" GNU
+.Dl \&.TH CVS 5 "1992-02-12" GNU
.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
.Sx \&P ,
and
.Sx \&PP .
-.\" .
-.\" .
-.\" .Ss \&PD
-.\" Has no effect. Included for compatibility.
-.\" .
-.\" .
.Ss \&UC
Sets the volume for the footer for compatibility with man pages from
BSD releases.
.Ss \&fi
End literal mode begun by
.Sx \&nf .
-.Ss \&i
-Italicise arguments.
-Synonym for
-.Sx \&I .
+.Ss \&ft
+Change the current font mode.
+See
+.Sx Text Decoration
+for a listing of available font modes.
+.Ss \&in
+Indent relative to the current indentation:
.Pp
-See also
-.Sx \&B ,
-.Sx \&I ,
-.Sx \&R .
-.Sx \&b ,
-and
-.Sx \&r .
+.D1 Pf \. Sx \&in Op Cm width
+.Pp
+If
+.Cm width
+is signed, the new offset is relative.
+Otherwise, it is absolute.
+This value is reset upon the next paragraph, section, or sub-section.
.Ss \&na
Don't align to the right margin.
.Ss \&nf
line boundaries preserved.
May be ended by
.Sx \&fi .
-.Ss \&r
-Fonts and styles (bold face, italics) reset to roman (default font).
-.Pp
-See also
-.Sx \&B ,
-.Sx \&I ,
-.Sx \&R ,
-.Sx \&b ,
-and
-.Sx \&i .
+Literal mode is implicitly ended by
+.Sx \&SH
+or
+.Sx \&SS .
.Ss \&sp
Insert vertical spaces into output with the following syntax:
.Bd -filled -offset indent
.Pp
See also
.Sx \&br .
-.\" .Ss \&Sp
-.\" A synonym for
-.\" .Sx \&sp
-.\" .Cm 0.5v .
-.\" .
-.\" .Ss \&Vb
-.\" A synonym for
-.\" .Sx \&nf .
-.\" Accepts an argument (the height of the formatted space) which is
-.\" disregarded.
-.\" .
-.\" .Ss \&Ve
-.\" A synonym for
-.\" .Sx \&fi .
-.\" .
.Sh COMPATIBILITY
This section documents areas of questionable portability between
implementations of the
.Pp
.Bl -dash -compact
.It
-The \es (font size), \em (font colour), and \eM (font filling colour)
-font decoration escapes are all discarded in mandoc.
-.It
In quoted literals, GNU troff allowed pair-wise double-quotes to produce
a standalone double-quote in formatted output.
It is not known whether this behaviour is exhibited by other formatters.
.It
+troff suppresses a newline before
+.Sq \(aq
+macro output; in mandoc, it is an alias for the standard
+.Sq \&.
+control character.
+.It
+The
+.Sq \eh
+.Pq horizontal position ,
+.Sq \ev
+.Pq vertical position ,
+.Sq \em
+.Pq text colour ,
+.Sq \eM
+.Pq text filling colour ,
+.Sq \ez
+.Pq zero-length character ,
+.Sq \ew
+.Pq string length ,
+.Sq \ek
+.Pq horizontal position marker ,
+.Sq \eo
+.Pq text overstrike ,
+and
+.Sq \es
+.Pq text size
+escape sequences are all discarded in mandoc.
+.It
+The
+.Sq \ef
+scaling unit is accepted by mandoc, but rendered as the default unit.
+.It
The
.Sx \&sp
macro does not accept negative values in mandoc.
In GNU troff, this would result in strange behaviour.
-.It
-The
-.Sq \(aq
-macro control character, in GNU troff (and prior troffs) suppresses a
-newline before macro output; in mandoc, it is an alias for the standard
-.Sq \&.
-control character.
.El
.Sh SEE ALSO
+.Xr man 1 ,
.Xr mandoc 1 ,
-.Xr mandoc_char 7
-.Sh AUTHORS
+.Xr eqn 7 ,
+.Xr mandoc_char 7 ,
+.Xr mdoc 7 ,
+.Xr roff 7 ,
+.Xr tbl 7
+.Sh HISTORY
The
.Nm
+language first appeared as a macro package for the roff typesetting
+system in
+.At v7 .
+It was later rewritten by James Clark as a macro package for groff.
+The stand-alone implementation that is part of the
+.Xr mandoc 1
+utility written by Kristaps Dzonsons appeared in
+.Ox 4.6 .
+.Sh AUTHORS
+This
+.Nm
reference was written by
-.An Kristaps Dzonsons Aq kristaps@bsd.lv .
+.An Kristaps Dzonsons ,
+.Mt kristaps@bsd.lv .
.Sh CAVEATS
Do not use this language.
Use
git.ckatri.com / mandoc.git / blobdiff