-.\" $Id: man.7,v 1.59 2010/03/27 10:10:10 kristaps Exp $
+.\" $Id: man.7,v 1.66 2010/05/08 22:26:39 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
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
-.Dd $Mdocdate: March 27 2010 $
+.Dd $Mdocdate: May 8 2010 $
.Dt MAN 7
.Os
-.
-.
.Sh NAME
.Nm man
.Nd man language reference
-.
-.
.Sh DESCRIPTION
The
.Nm man
.Ux
manuals. This reference document describes its syntax, structure, and
usage.
-.
.Pp
.Bf -emphasis
Do not use
Use the
.Xr mdoc 7
language, instead.
-.
.Pp
An
.Nm
\&.SH Macro lines change control state.
Other lines are interpreted within the current state.
.Ed
-.
-.
.Sh INPUT ENCODING
.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.
-.
-.
.Ss Comments
Text following a
.Sq \e\*" ,
.Sq \&.\e" ,
is also ignored. Macro lines with only a control character and
optionally whitespace are stripped from input.
-.
-.
.Ss Special Characters
Special characters may occur in both macro and free-form lines.
Sequences begin with the escape character
and
.Sq \ee
.Pq back-slash .
-.
-.
.Ss Text Decoration
Terms may be text-decorated using the
.Sq \ef
and
.Sq \ef
attributes are forgotten when entering or exiting a macro block.
-.
-.
.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 .
-.
-.
+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 macro lines, whitespace delimits arguments and is discarded. If
+arguments are quoted, whitespace within the quotes is retained.
.Ss Dates
The
.Sx \&TH
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:]? ,
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
or
.Sq v
is necessarily non-portable across output media.
-.
.Pp
If a scaling unit is not provided, the numerical value is interpreted
under the default rules of
.Xr mdoc 7 ,
which, if a unit is not provided, will instead interpret the string as
literal text.
-.
-.
.Sh MANUAL STRUCTURE
Each
.Nm
macro describing the document's section and title. It may occur
anywhere in the document, although conventionally, it appears as the
first macro.
-.
.Pp
Beyond
.Sx \&TH ,
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!
-.
.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.
.Pp
Cross-references should conventionally be ordered
first by section, then alphabetically.
-.
.It Em STANDARDS
References any standards implemented or used, such as
.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 ,
at the beginning of the line. The
.Sq \(aq
macro control character is also accepted. An arbitrary amount of
-whitespace may sit between the control character and the macro name.
-Thus, the following are equivalent:
+whitespace (spaces or tabs) may sit between the control character and
+the macro name. Thus, the following are equivalent:
.Bd -literal -offset indent
\&.PP
\&.\ \ \ PP
.Ed
-.
.Pp
The
.Nm
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
\&.I
foo
.Ed
-.
.Pp
is equivalent to
.Sq \&.I foo .
raised (unless in the case of
.Sx \&br ,
.Sx \&sp ,
-.Sx \&Sp ,
or
.Sx \&na ) .
.Pp
\&.YO \(lBbody...\(rB
\(lBbody...\(rB
.Ed
-.
.Pp
.Bl -column -compact -offset indent "MacroX" "ArgumentsX" "ScopeXXXXX" "CompatX"
.It Em Macro Ta Em Arguments Ta Em Scope Ta Em Notes
.\" .It Sx \&Vb Ta <1 Ta current Ta compat
.\" .It Sx \&Ve Ta 0 Ta current Ta compat
.El
-.
.Pp
Macros marked as
.Qq compat
portable
.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 one circumstance, the
\(lBhead...\(rB
\(lBbody...\(rB
.Ed
-.
.Pp
The closure of body scope may be to the section, where a macro is closed
by
or
.Sx \&TP .
No closure refers to an explicit block closing macro.
-.
.Pp
As a rule, block macros may not be nested; thus, calling a block macro
while another block macro scope is open, and the open scope is not
implicitly closed, is syntactically incorrect.
-.
.Pp
.Bl -column -compact -offset indent "MacroX" "ArgumentsX" "Head ScopeX" "sub-sectionX" "compatX"
.It Em Macro Ta Em Arguments Ta Em Head Scope Ta Em Body Scope Ta Em Notes
.It Sx \&TP Ta n Ta next-line Ta paragraph Ta \&
.El
.Pp
-.
Macros marked
.Qq compat
are as mentioned in
.Sx Line Macros .
-.
.Pp
If a block macro is next-line scoped, it may only be followed by in-line
macros for decorating text.
-.
-.
.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.
.Pp
.Sx \&i ,
and
.Sx \&r .
-.
-.
.Ss \&BI
Text is rendered alternately in bold face and italic. Thus,
.Sq .BI this word and that
.Sx \&RI ,
and
.Sx \&IR .
-.
-.
.Ss \&BR
Text is rendered alternately in bold face and roman (the default font).
Whitespace between arguments is omitted in output.
.Sx \&RI ,
and
.Sx \&IR .
-.
-.
.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:
.Sx \&PP ,
and
.Sx \&TP .
-.
-.
.Ss \&I
Text is rendered in italics.
.Pp
.Sx \&i ,
and
.Sx \&r .
-.
-.
.Ss \&IB
Text is rendered alternately in italics and bold face. Whitespace
between arguments is omitted in output.
.Sx \&RI ,
and
.Sx \&IR .
-.
-.
.Ss \&IP
Begin an indented paragraph with the following syntax:
.Bd -filled -offset indent
.Sx \&PP ,
and
.Sx \&TP .
-.
-.
.Ss \&IR
Text is rendered alternately in italics and roman (the default font).
Whitespace between arguments is omitted in output.
.Sx \&RB ,
and
.Sx \&RI .
-.
-.
.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
.Sx \&PP ,
and
.Sx \&TP .
-.
-.
.Ss \&P
Synonym for
.Sx \&LP .
.Sx \&PP ,
and
.Sx \&TP .
-.
-.
.Ss \&PP
Synonym for
.Sx \&LP .
.Sx \&P ,
and
.Sx \&TP .
-.
-.
.Ss \&R
Text is rendered in roman (the default font).
.Pp
.Sx \&i ,
and
.Sx \&r .
-.
-.
.Ss \&RB
Text is rendered alternately in roman (the default font) and bold face.
Whitespace between arguments is omitted in output.
.Sx \&RI ,
and
.Sx \&IR .
-.
-.
.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.
.Sx \&RB ,
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
argument must conform to
.Sx Scaling Widths .
If 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:
.Bd -filled -offset indent
Examples:
.Pp
.D1 \&.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
.\" .
.\" .Ss \&UC
.\" Has no effect. Included for compatibility.
-.
-.
.Ss \&br
Breaks the current line. Consecutive invocations have no further effect.
.Pp
See also
.Sx \&sp .
-.
-.
.Ss \&fi
End literal mode begun by
.Sx \&nf .
-.
-.
.Ss \&i
Italicise arguments. Synonym for
.Sx \&I .
.Sx \&b ,
and
.Sx \&r .
-.
-.
.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).
.Pp
.Sx \&b ,
and
.Sx \&i .
-.
-.
.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
.\" A synonym for
.\" .Sx \&fi .
.\" .
-.
.Sh COMPATIBILITY
This section documents areas of questionable portability between
implementations of the
.Nm
language.
-.
.Pp
.Bl -dash -compact
.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
-Blocks of whitespace are stripped from macro and free-form text lines
-(except when in literal mode) in mandoc. This is not the case for GNU
-troff: for maximum portability, whitespace sensitive blocks should be
-enclosed in literal contexts.
-.
.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
.Sq \&.
control character.
.El
-.
-.
.Sh SEE ALSO
.Xr mandoc 1 ,
.Xr mandoc_char 7
-.
-.
.Sh AUTHORS
The
.Nm
reference was written by
-.An Kristaps Dzonsons Aq kristaps@kth.se .
-.
-.
+.An Kristaps Dzonsons Aq kristaps@bsd.lv .
.Sh CAVEATS
Do not use this language. Use
.Xr mdoc 7 ,
instead.
-.
git.ckatri.com / mandoc.git / blobdiff