-.\" $Id: mdoc.7,v 1.83 2010/01/30 08:55:39 kristaps Exp $
+.\" $Id: mdoc.7,v 1.98 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: January 30 2010 $
+.Dd $Mdocdate: May 8 2010 $
.Dt MDOC 7
.Os
-.
-.
.Sh NAME
.Nm mdoc
.Nd mdoc language reference
-.
-.
.Sh DESCRIPTION
The
.Nm mdoc
.Bx
.Ux
manuals. In this reference document, we describe its syntax, structure,
-and usage. Our reference implementation is
-.Xr mandoc 1 .
-The
+and usage. Our reference implementation is mandoc; the
.Sx COMPATIBILITY
-section describes compatibility with
-.Xr groff 1 .
-.
+section describes compatibility with other troff \-mdoc implementations.
.Pp
An
.Nm
\&.Sh Macro lines change control state.
Other lines are interpreted within the current state.
.Ed
-.
-.
.Sh LANGUAGE SYNTAX
.Nm
documents may contain only graphable 7-bit ASCII characters, the space
manuals must have
.Ux
line terminators.
-.
-.
.Ss Comments
Text following a
.Sq \e" ,
.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:
.Pp
.It \&|
.Pq vertical bar
.El
-.
.Pp
Use of reserved characters is described in
.Sx MACRO SYNTAX .
with a non-breaking space
.Pq Sq \e&
or, if applicable, an appropriate escape sequence used.
-.
-.
.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
recommended for
.Nm ,
which encourages semantic annotation.
-.
-.
.Ss Predefined Strings
Historically,
.Xr groff 1
and
.Sq \e*(Ba
.Pq vertical bar .
-.
-.
.Ss Whitespace
-In non-literal free-form lines, consecutive blocks of whitespace are
-pruned from input and added later in the output filter, if applicable:
-.Bd -literal -offset indent
-These spaces are pruned from input.
-\&.Bd \-literal
-These are not.
-\&.Ed
-.Ed
-.
+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.
-.
-.Pp
-Blank lines are only permitted within literal contexts, as are lines
-containing only whitespace. Tab characters are only acceptable when
-delimiting
-.Sq \&Bl \-column
-or when in a literal context.
-.
-.
.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" ,
.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
.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:] ,
.Sq v
is necessarily non-portable across output media. See
.Sx COMPATIBILITY .
-.
-.
.Sh MANUAL STRUCTURE
A well-formed
.Nm
.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 or 3 manual. The syntax for
.Pp
See
.Sx \&Lb .
-.
.It Em SYNOPSIS
Documents the utility invocation syntax, function call syntax, or device
configuration.
.Sx \&Ft ,
and
.Sx \&Vt .
-.
.It Em DESCRIPTION
This expands upon the brief, one-line description in
.Em NAME .
.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 EXIT STATUS
Command exit status for section 1, 6, and 8 manuals. This section is
the dual of
.Pp
See
.Sx \&Ex .
-.
.It Em RETURN VALUES
This section is the dual of
.Em EXIT STATUS ,
.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 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
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
.Pp
See
.Sx \&Xr .
-.
.It Em STANDARDS
References any standards implemented or used. If not adhering to any
standards, the
.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 ,
\&.Pp
\&.\ \ \ \&Pp
.Ed
-.
.Pp
The syntax of a macro depends on its classification. In this section,
.Sq \-arg
opens the scope of a macro; and if specified,
.Sq \&Yc
closes it out.
-.
.Pp
The
.Em Callable
.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
\(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 \&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
Multi-line scope closed by end-of-file or implicitly by another macro.
All macros have bodies; some
\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB
\(lBbody...\(rB
.Ed
-.
.Pp
.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 \&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
-.
-.
.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
\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \
\(lBbody...\(rB \&Yc \(lBtail...\(rB
.Ed
-.
.Pp
.Bl -column "MacroX" "CallableX" "ParsableX" "closed by XXXX" -compact -offset indent
.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Scope
.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
-.
-.
.Ss Block partial-implicit
Like block full-implicit, but with single-line scope closed by
.Sx Reserved Characters
.Bd -literal -offset indent
\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB
.Ed
-.
.Pp
.Bl -column "MacroX" "CallableX" "ParsableX" -compact -offset indent
.It Em Macro Ta Em Callable Ta Em Parsable
only when invoked as the first macro
in a SYNOPSIS section line, else it is
.Sx In-line .
-.
-.
.Ss In-line
Closed by
.Sx Reserved Characters ,
\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
.Ed
-.
.Pp
.Bl -column "MacroX" "CallableX" "ParsableX" "Arguments" -compact -offset indent
.It Em Macro Ta Em Callable Ta Em Parsable Ta Em Arguments
.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 \&No Ta Yes Ta 1
+.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 \&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, <3
+.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
.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
.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:
-.Bd -literal -offset indent
-\&.Ad [0,$]
-\&.Ad 0x00000000
-.Ed
-.
+.D1 \&.Ad [0,$]
+.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:
section, the default is not to split.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.An -nosplit
-\&.An J. E. Hopcraft ,
-\&.An J. D. Ullman .
-.Ed
+.D1 \&.An -nosplit
+.D1 \&.An J. D. Ullman .
.Pp
.Em Remarks :
the effects of
.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:
-.Bd -literal -offset indent
-\&.Fl -key= Ns Ao Ar val Ac
-.Ed
+.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
.Bd -literal -offset indent
\&.Fn execve Ap d
.Ed
-.
.Ss \&Aq
Encloses its arguments in angled brackets.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Fl -key= Ns Aq Ar val
-.Ed
+.D1 \&.Fl -key= \&Ns \&Aq \&Ar val
.Pp
.Em Remarks :
this macro is often abused for rendering URIs, which should instead use
.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:
-.Bd -literal -offset indent
-\&.Fl o Ns Ar file1
-\&.Ar
-\&.Ar arg1 , arg2 .
-.Ed
-.
+.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
Note that these parameters do not begin with a hyphen.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.At
-\&.At V.1
-.Ed
+.D1 \&.At
+.D1 \&.At V.1
.Pp
See also
.Sx \&Bsx ,
.Sx \&Ox ,
and
.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
.Sx \&D1
and
.Sx \&Dl .
-.
.Ss \&Bf
.Ss \&Bk
.Ss \&Bl
Examples:
.Bd -literal -offset indent
\&.Bo 1 ,
-\&.Dv BUFSIZ Bc
+\&.Dv BUFSIZ \&Bc
.Ed
.Pp
See also
.Sx \&Bq .
-.
.Ss \&Bq
Encloses its arguments in square brackets.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Bq 1 , Dv BUFSIZ
-.Ed
+.D1 \&.Bq 1 , \&Dv BUFSIZ
.Pp
.Em Remarks :
this macro is sometimes abused to emulate optional arguments for
.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.
Examples:
.Bd -literal -offset indent
\&.Bro 1 , ... ,
-\&.Va n Brc
+\&.Va n \&Brc
.Ed
.Pp
See also
.Sx \&Brq .
-.
.Ss \&Brq
Encloses its arguments in curly braces.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Brq 1 , ... , Va n
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Bsx 1.0
-\&.Bsx
-.Ed
+.D1 \&.Bsx 1.0
+.D1 \&.Bsx
.Pp
See also
.Sx \&At ,
.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:
-.Bd -literal -offset indent
-\&.Bx 4.4
-\&.Bx
-.Ed
+.D1 \&.Bx 4.4
+.D1 \&.Bx
.Pp
See also
.Sx \&At ,
.Sx \&Ox ,
and
.Sx \&Ux .
-.
.Ss \&Cd
-Configuration declaration (suggested for use only in section four
-manuals). This denotes strings accepted by
+Configuration declaration. This denotes strings accepted by
.Xr config 8 .
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Cd device le0 at scode?
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Cm ControlPath
-\&.Cm ControlMaster
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.D1 Fl abcdefgh
-.Ed
+.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
If a date does not conform, the current date is used instead.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Dd $\&Mdocdate$
-\&.Dd $\&Mdocdate: July 21 2007$
-\&.Dd July 21, 2007
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Dl % mandoc mdoc.7 | less
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.D1 Do April is the cruellest month Dc \e(em T.S. Eliot
-.Ed
+.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
+.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
.Ar hppa64 ,
.Ar i386 ,
.Ar landisk ,
+.Ar loongson ,
.Ar luna88k ,
.Ar mac68k ,
.Ar macppc ,
.El
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Dt FOO 1
-\&.Dt FOO 4 KM
-\&.Dt FOO 9 i386
-\&.Dt FOO 9 KM i386
-.Ed
+.D1 \&.Dt FOO 1
+.D1 \&.Dt FOO 4 KM
+.D1 \&.Dt FOO 9 i386
+.D1 \&.Dt FOO 9 KM i386
.Pp
See also
.Sx \&Dd
and
.Sx \&Os .
-.
.Ss \&Dv
Defined variables such as preprocessor constants.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Dv BUFSIZ
-\&.Dv STDOUT_FILENO
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Dx 2.4.1
-\&.Dx
-.Ed
+.D1 \&.Dx 2.4.1
+.D1 \&.Dx
.Pp
See also
.Sx \&At ,
.Sx \&Ox ,
and
.Sx \&Ux .
-.
.Ss \&Ec
.Ss \&Ed
.Ss \&Ef
technical terms.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Ed Warnings!
-\&.Ed Remarks :
-.Ed
-.
+.D1 \&.Em Warnings!
+.D1 \&.Em Remarks :
.Ss \&En
.Ss \&Eo
.Ss \&Er
-Error constants (suggested for use only in section two manuals).
+Display error constants.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Er EPERM
-\&.Er ENOENT
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Ev DISPLAY
-\&.Ev PATH
-.Ed
-.
+.D1 \&.Ev DISPLAY
+.D1 \&.Ev PATH
.Ss \&Ex
Inserts text regarding a utility's exit values. This macro must have
first the
Command-line flag. Used when listing arguments to command-line
utilities. Prints a fixed-width hyphen
.Sq \-
-before each delimited argument. If no arguments are provided, a hyphen
-is still printed.
+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:
-.Bd -literal -offset indent
-\&.Fl a b c
-\&.Fl
-\&.Op Fl o Ns Ar file
-.Ed
+.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
if no argument is provided.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Fx 7.1
-\&.Fx
-.Ed
+.D1 \&.Fx 7.1
+.D1 \&.Fx
.Pp
See also
.Sx \&At ,
.Sx \&Ox ,
and
.Sx \&Ux .
-.
.Ss \&Hf
.Ss \&Ic
.Ss \&In
.D1 \. Ns Sx \&Lk Cm uri Op Cm name
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Lk http://bsd.lv "The BSD.lv Project"
-\&.Lk http://bsd.lv
-.Ed
+.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
no argument is provided.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Nx 5.01
-\&.Nx
-.Ed
+.D1 \&.Nx 5.01
+.D1 \&.Nx
.Pp
See also
.Sx \&At ,
.Sx \&Ox ,
and
.Sx \&Ux .
-.
.Ss \&Oc
.Ss \&Oo
.Ss \&Op
the suggested form.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Os
-\&.Os KTH/CSC/TCS
-\&.Os BSD 4.3
-.Ed
+.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:
-.Bd -literal -offset indent
-\&.Ox 4.5
-\&.Ox
-.Ed
+.D1 \&.Ox 4.5
+.D1 \&.Ox
.Pp
See also
.Sx \&At ,
.Sx \&Nx ,
and
.Sx \&Ux .
-.
.Ss \&Pa
.Ss \&Pc
.Ss \&Pf
.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
child macros (at least one must be specified).
.Pp
Examples:
-.Bd -literal -offset indent
+.Bd -literal -offset indent -compact
\&.Rs
\&.%A J. E. Hopcroft
\&.%A J. D. Ullman
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
Format the UNIX name. Accepts no argument.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Ux
-.Ed
+.D1 \&.Ux
.Pp
See also
.Sx \&At ,
.Sx \&Nx ,
and
.Sx \&Ox .
-.
.Ss \&Va
.Ss \&Vt
A variable type. This is also used for indicating global variables in the
which is used for function return types.
.Pp
Examples:
-.Bd -literal -offset indent
-\&.Vt unsigned char
-\&.Vt extern const char * const sys_signame[] ;
-.Ed
+.D1 \&.Vt unsigned char
+.D1 \&.Vt extern const char * const sys_signame[] ;
.Pp
See also
.Sx \&Ft
and
.Sx \&Va .
-.
-.
-.Sh COMPATIBILITY
-This section documents compatibility with other roff implementations, at
-this time limited to
+.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 those versions before the
+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
.It
.Sq \e."
is no longer accepted.
.It
-In
-.Xr groff 1 ,
-the
+In groff, the
.Sx \&Pa
macro does not format its arguments when used in the FILES section under
-certain list types. This irregular behaviour has been discontinued.
+certain list types. mandoc does.
.It
-Historic
-.Xr groff 1
-does not print a dash for empty
+Historic groff does not print a dash for empty
.Sx \&Fl
-arguments. This behaviour has been discontinued.
+arguments. mandoc and newer groff implementations do.
.It
-.Xr groff 1
-behaves strangely (even between versions) when specifying
+groff behaves irregularly when specifying
.Sq \ef
-escapes within line-macro scopes. These aberrations have been
-normalised.
+.Sx Text Decoration
+within line-macro scopes. mandoc follows a consistent system.
.It
-Negative scaling units are now truncated to zero instead of creating
-interesting conditions, such as with
-.Sx \&sp
-.Fl 1i .
-Furthermore, the
+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
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.
+behaviour is not applicable in mandoc.
.It
Display types
.Sx \&Bd
and
.Fl right
are aliases for
-.Fl left .
-The
+.Fl left
+in manodc. Furthermore, the
.Fl file Ar file
-argument is ignored. Since text is not right-justified,
+argument is ignored. Lastly, since text is not right-justified in
+mandoc (or even groff),
.Fl ragged
and
.Fl filled
and
.Fl unfilled .
.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.
-.It
Historic groff has many un-callable macros. Most of these (excluding
-some block-level macros) are now callable, conforming to the
-non-historic groff version.
+some block-level macros) are now callable.
.It
The vertical bar
.Sq \(ba
made historic groff
.Qq go orbital
-but is a proper delimiter in this implementation.
+but has been a proper delimiter since then.
.It
-.Sx \&It
-.Fl nested
+.Sx \&It Fl nested
is assumed for all lists (it wasn't in historic groff): any list may be
nested and
.Fl enum
Some manuals use
.Sx \&Li
incorrectly by following it with a reserved character and expecting the
-delimiter to render. This is not supported.
+delimiter to render. This is not supported in mandoc.
.It
In groff, the
.Sx \&Fo
-macro only produces the first parameter. This is no longer the case.
+macro only produces the first parameter. This is not the case in
+mandoc.
+.It
+In groff, the
+.Sx \&Cd ,
+.Sx \&Er ,
+and
+.Sx \&Ex
+macros were stipulated only to occur in certain manual sections. mandoc
+does not have these restrictions.
.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 .
.\"
.\" XXX: this really isn't the place for these caveats.
.\" .