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Diff for /mandoc/mdoc.7 between version 1.125 and 1.153

version 1.125, 2010/06/12 10:09:19

version 1.153, 2010/08/24 13:07:01

Line 1

.\" $Id$

.\"

.\" Permission to use, copy, modify, and distribute this software for any

.\" purpose with or without fee is hereby granted, provided that the above

Line 26 The

Line 27 The

language is used to format

.Bx

.Ux

manuals. In this reference document, we describe its syntax, structure,

manuals.

and usage. Our reference implementation is mandoc; the

This reference document describes its syntax, structure, and

usage.

The reference implementation is

.Xr mandoc 1 ;

the

.Sx COMPATIBILITY

section describes compatibility with other troff \-mdoc implementations.

.Pp

Line 36 An

Line 41 An

document follows simple rules: lines beginning with the control

character

.Sq \.

are parsed for macros. Other lines are interpreted within the scope of

are parsed for macros.

Other lines are interpreted within the scope of

prior macros:

.Bd -literal -offset indent

\&.Sh Macro lines change control state.

Line 45 Other lines are interpreted within the current state.

Line 51 Other lines are interpreted within the current state.

.Sh LANGUAGE SYNTAX

.Nm

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

character, and, in certain circumstances, the tab character. All

character, and, in certain circumstances, the tab character.

manuals must have

All manuals must have

.Ux

line terminators.

.Ss Comments

Text following a

.Sq \e" ,

.Sq \e\*q ,

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,

line.

.Sq \&.\e" ,

A macro line with only a control character and comment escape,

is also ignored. Macro lines with only a control character and optionally

.Sq \&.\e\*q ,

whitespace are stripped from input.

is also ignored.

Macro lines with only a control character and optional whitespace are

stripped from input.

.Ss Reserved Characters

Within a macro line, the following characters are reserved:

.Pp

Line 87 Within a macro line, the following characters are rese

Line 95 Within a macro line, the following characters are rese

.Pp

Use of reserved characters is described in

.Sx MACRO SYNTAX .

For general use in macro lines, these characters must either be escaped

For general use in macro lines, these characters can either be escaped

with a non-breaking space

.Pq Sq \e&

or, if applicable, an appropriate escape sequence used.

or, if applicable, an appropriate escape sequence can be used.

.Ss Special Characters

Special characters may occur in both macro and free-form lines.

Sequences begin with the escape character

Line 101 for two-character sequences; an open-bracket

Line 109 for two-character sequences; an open-bracket

.Sq \&[

for n-character sequences (terminated at a close-bracket

.Sq \&] ) ;

or a single one-character sequence.

or a single one character sequence.

See

.Xr mandoc_char 7

for a complete list.

Line 114 and

Line 122 and

.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 (Roman), or P

(revert to previous mode):

.Pp

.D1 \efBbold\efR \efIitalic\efP

Line 134 If

Line 142 If

is specified outside of any font scope, such as in unenclosed, free-form

text, it will affect the remainder of the document.

.Pp

Text may also be sized with the

Note this form is

.Sq \es

escape, whose syntax is one of

.Sq \es+-n

for one-digit numerals;

.Sq \es(+-nn

.Sq \es+-(nn

for two-digit numerals; and

.Sq \es[+-N] ,

.Sq \es+-[N] ,

.Sq \es'+-N' ,

.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

troff

also defined a set of package-specific

.Dq predefined strings ,

which, like

Line 187 and

Line 174 and

.Pq vertical bar .

.Ss Whitespace

Whitespace consists of the space character.

In free-form lines, whitespace is preserved within a line; un-escaped

In free-form lines, whitespace is preserved within a line; unescaped

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.

Line 195 within literal contexts.

Line 182 within literal contexts.

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

Macro arguments may be quoted with double-quotes 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

The next double-quote not pairwise adjacent to another double-quote

terminates the literal, regardless of surrounding whitespace.

.Pp

This produces tokens

Note that any quoted text, even if it would cause a macro invocation

.Sq a" ,

when unquoted, is considered literal text.

.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 :

.Sq Op "Fl a" :

.Bd -literal -offset indent

\&.Em "Em a"

\&.Op "Fl a"

.Ed

.Pp

In free-form mode, quotes are regarded as opaque text.

Line 297 is necessarily non-portable across output media.

Line 278 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

When composing a manual, make sure that 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,

Line 309 delimiters (

Line 290 delimiters (

.Sq \&" ) .

.Pp

The proper spacing is also intelligently preserved if a sentence ends at

the boundary of a macro line, e.g.,

the boundary of a macro line.

For example:

.Pp

.D1 \&Xr mandoc 1 \.

.D1 \&Fl T \&Ns \&Cm ascii \.

Line 319 A well-formed

Line 301 A well-formed

document consists of a document prologue followed by one or more

sections.

.Pp

The prologue, which consists of (in order) the

The prologue, which consists of the

.Sx \&Dd ,

.Sx \&Dt ,

and

.Sx \&Os

macros, is required for every document.

macros in that order, is required for every document.

.Pp

The first section (sections are denoted by

.Sx \&Sh )

Line 382 utility processes files ...

Line 364 utility processes files ...

\&.\e\*q .Sh SECURITY CONSIDERATIONS

.Ed

.Pp

The sections in a

The sections in an

.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 name(s) and a one line description of the documented material.

The syntax for this as follows:

.Bd -literal -offset indent

\&.Nm name0

\&.Nm name0 ,

\&.Nm name1

\&.Nm name1 ,

\&.Nm name2

\&.Nd a short description

\&.Nd a one line description

.Ed

.Pp

The

Line 436 generally structured as follows:

Line 418 generally structured as follows:

.Pp

For the second, function calls (sections 2, 3, 9):

.Bd -literal -offset indent

\&.Vt extern const char *global;

\&.In header.h

\&.Vt extern const char *global;

\&.Ft "char *"

\&.Fn foo "const char *src"

\&.Ft "char *"

Line 465 section, particularly

Line 447 section, particularly

.Sx \&Vt ,

and

.Sx \&Ft .

All of these macros are output on their own line. If two such

All of these macros are output on their own line.

dissimilar macros are pair-wise invoked (except for

If two such dissimilar macros are pairwise invoked (except for

.Sx \&Ft

before

.Sx \&Fo

Line 478 they are separated by a vertical space, unless in the

Line 460 they are separated by a vertical space, unless in the

and

.Sx \&Ft ,

which are always separated by vertical space.

.Pp

When text and macros following an

.Sx \&Nm

macro starting an input line span multiple output lines,

all output lines but the first will be indented to align

with the text immediately following the

.Sx \&Nm

macro, up to the next

.Sx \&Nm ,

.Sx \&Sh ,

.Sx \&Ss

macro or the end of an enclosing block, whichever comes first.

.It Em DESCRIPTION

This expands upon the brief, one-line description in

This expands upon the brief, one line description in

.Em NAME .

It usually contains a break-down of the options (if documenting a

It usually contains a breakdown of the options (if documenting a

command), such as:

.Bd -literal -offset indent

The arguments are as follows:

Line 497 Implementation-specific notes should be kept here.

Line 492 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

This section documents the

.Em EXIT STATUS ,

return values of functions in sections 2, 3, and 9.

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.,

Lists the environment variables used by the utility,

.Xr environ 7 .

and explains the syntax and semantics of their values.

The

.Xr environ 7

manual provides examples of typical content and formatting.

.Pp

See

.Sx \&Ev .

.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.).

.Pp

See

.Sx \&Pa .

.It Em EXIT STATUS

Command exit status for section 1, 6, and 8 manuals.

This section documents the

This section is the dual of

command exit status for section 1, 6, and 8 utilities.

.Em RETURN VALUES ,

which is used for functions.

Historically, this information was described in

.Em DIAGNOSTICS ,

a practise that is now discouraged.

Line 531 See

Line 525 See

.It Em EXAMPLES

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.

Line 565 section should be used instead.

Line 559 section should be used instead.

See

.Sx \&St .

.It Em HISTORY

The history of any manual without a

A brief history of the subject, including where support first appeared.

.Em STANDARDS

section should be described in this section.

.It Em AUTHORS

Credits to authors, if applicable, should appear in this section.

Credits to the person or persons who wrote the code and/or documentation.

Authors should generally be noted by both name and an e-mail address.

Authors should generally be noted by both name and email address.

.Pp

See

.Sx \&An .

.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 ,

control character,

.Sq \&. ,

at the beginning of the line.

An arbitrary amount of whitespace may sit between the control character

Line 617 produces

Line 610 produces

.Sq Fl \&Sh .

.Pp

The

.Em Parsable

.Em Parsed

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

If a macro is not parsed, subsequent macro invocations on the line

will be interpreted as opaque text.

.Pp

The

Line 637 contains a head.

Line 630 contains a head.

\&.Yc

.Ed

.Pp

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

.Bl -column -compact -offset indent "MacroX" "CallableX" "ParsedX" "closed by XXX"

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

.It Em Macro Ta Em Callable Ta Em Parsed 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

Line 660 All macros have bodies; some

Line 653 All macros have bodies; some

.Pc

don't have heads; only one

.Po

.Sx \&It Fl column

.Sx \&It

.Sx \&Bl Fl column

.Pc

has multiple heads.

.Bd -literal -offset indent

Line 668 has multiple heads.

Line 663 has multiple heads.

\(lBbody...\(rB

.Ed

.Pp

.Bl -column -compact -offset indent "MacroX" "CallableX" "ParsableX" "closed by XXXXXXXXXXX"

.Bl -column -compact -offset indent "MacroX" "CallableX" "ParsedX" "closed by XXXXXXXXXXX"

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

.It Em Macro Ta Em Callable Ta Em Parsed 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 \&Nm Ta \&No Ta Yes Ta closed by Sx \&Nm , Sx \&Sh , Sx \&Ss

.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

.Pp

Note that the

.Sx \&Nm

macro is a

.Sx Block full-implicit

macro only when invoked as the first macro

in a

.Em SYNOPSIS

section line, else it is

.Sx In-line .

.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

Line 693 and/or tail

Line 699 and/or tail

\(lBbody...\(rB \&Yc \(lBtail...\(rB

.Ed

.Pp

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

.Bl -column "MacroX" "CallableX" "ParsedX" "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 Parsed Ta Em Scope

.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

Line 728 or end of line.

Line 734 or end of line.

\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB

.Ed

.Pp

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

.Bl -column "MacroX" "CallableX" "ParsedX" -compact -offset indent

.It Em Macro Ta Em Callable Ta Em Parsable

.It Em Macro Ta Em Callable Ta Em Parsed

.It Sx \&Aq Ta Yes Ta Yes

.It Sx \&Bq Ta Yes Ta Yes

.It Sx \&Brq Ta Yes Ta Yes

Line 762 If a number (or inequality) of arguments is

Line 768 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 \(lBres...\(rB

\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc...

\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN

.Ed

.Pp

.Bl -column "MacroX" "CallableX" "ParsableX" "Arguments" -compact -offset indent

.Bl -column "MacroX" "CallableX" "ParsedX" "Arguments" -compact -offset indent

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

.It Em Macro Ta Em Callable Ta Em Parsed 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

Line 796 then the macro accepts an arbitrary number of argument

Line 802 then the macro accepts an arbitrary number of argument

.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 \&Dd Ta \&No Ta \&No Ta n

.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

Line 854 For the scoping of individual macros, see

Line 860 For the scoping of individual macros, see

.Ss \&%A

Author name of an

.Sx \&Rs

block. Multiple authors should each be accorded their own

block.

Multiple authors should each be accorded their own

.Sx \%%A

line. Author names should be ordered with full or abbreviated

line.

forename(s) first, then full surname.

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

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

.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

block.

described in

This should follow the reduced or canonical form syntax described in

.Sx Dates .

.Ss \&%I

Publisher or issuer name of an

Line 900 block.

Line 905 block.

.Ss \&%Q

Institutional author (school, government, etc.) of an

.Sx \&Rs

block. Multiple institutional authors should each be accorded their own

block.

Multiple institutional authors should each be accorded their own

.Sx \&%Q

line.

.Ss \&%R

Line 910 block.

Line 916 block.

.Ss \&%T

Article title of an

.Sx \&Rs

block. This macro may also be used in a non-bibliographical context

block.

when referring to article titles.

This macro may also be used in a non-bibliographical context when

referring to article titles.

.Ss \&%U

URI of reference document.

.Ss \&%V

Line 919 Volume number of an

Line 926 Volume number of an

.Sx \&Rs

block.

.Ss \&Ac

Closes an

Close an

.Sx \&Ao

block. Does not have any tail arguments.

block.

Does not have any tail arguments.

.Ss \&Ad

Address construct: usually in the context of an computational address in

Memory address.

memory, not a physical (post) address.

Do not use this for postal addresses.

.Pp

Examples:

.D1 \&.Ad [0,$]

.D1 \&.Ad 0x00000000

.Ss \&An

Author name.

This macro may alternatively accepts the following arguments, although

Requires either the name of an author or one of the following arguments:

these may not be specified along with a parameter:

.Pp

.Bl -tag -width 12n -offset indent

.Bl -tag -width "-nosplitX" -offset indent -compact

.It Fl split

Renders a line break before each author listing.

Start a new output line before each subsequent invocation of

.Sx \&An .

.It Fl nosplit

The opposite of

.Fl split .

.El

.Pp

In the AUTHORS section, the default is not to split the first author

The default is

listing, but all subsequent author listings, whether or not they're

.Fl nosplit .

interspersed by other macros or text, are split.

The effect of selecting either of the

Thus, specifying

.Fl split

will cause the first listing also to be split.

modes ends at the beginning of the

If not in the AUTHORS section, the default is not to split.

.Em AUTHORS

section.

In the

.Em AUTHORS

section, the default is

.Fl nosplit

for the first author listing and

.Fl split

for all other author listings.

.Pp

Examples:

.D1 \&.An -nosplit

.D1 \&.An J. D. Ullman .

.D1 \&.An Kristaps Dzonsons \&Aq kristaps@bsd.lv

.Pp

.Em Remarks :

the effects of

.Fl split

.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.

Begin a block enclosed by angle brackets.

Does not have any head arguments.

.Pp

Examples:

Line 972 Examples:

Line 978 Examples:

See also

.Sx \&Aq .

.Ss \&Ap

Inserts an apostrophe without any surrounding white-space.

Inserts an apostrophe without any surrounding whitespace.

This is generally used as a grammatical device when referring to the verb

form of a function:

form of a function.

.Bd -literal -offset indent

.Pp

\&.Fn execve Ap d

Examples:

.Ed

.D1 \&.Fn execve \&Ap d

.Ss \&Aq

Encloses its arguments in angled brackets.

Encloses its arguments in angle brackets.

.Pp

Examples:

.D1 \&.Fl -key= \&Ns \&Aq \&Ar val

Line 999 See also

Line 1005 See also

.Ss \&Ar

Command arguments.

If an argument is not provided, the string

.Dq file ...

.Dq file ...\&

is used as a default.

.Pp

Examples:

Line 1008 Examples:

Line 1014 Examples:

.D1 \&.Ar arg1 , arg2 .

.Ss \&At

Formats an AT&T version.

Accepts at most one parameter:

Accepts one optional argument:

.Bl -tag -width 12n -offset indent

.Pp

.Bl -tag -width "v[1-7] | 32vX" -offset indent -compact

.It Cm v[1-7] | 32v

A version of

.At .

.It Cm V[.[1-4]]?

A system version of

A version of

.At .

.At V .

.El

.Pp

Note that these parameters do not begin with a hyphen.

Note that these arguments do not begin with a hyphen.

.Pp

Examples:

.D1 \&.At

Line 1034 See also

Line 1041 See also

and

.Sx \&Ux .

.Ss \&Bc

Closes a

Close a

.Sx \&Bo

block. Does not have any tail arguments.

block.

Does not have any tail arguments.

.Ss \&Bd

Begins a display block.

Begin a display block.

A display is collection of macros or text which may be collectively

Its syntax is as follows:

offset or justified in a manner different from that

.Bd -ragged -offset indent

of the enclosing context.

.Pf \. Sx \&Bd

By default, the block is preceded by a vertical space.

.Fl Ns Ar type

.Op Fl offset Ar width

.Op Fl compact

.Ed

.Pp

Each display is associated with a type, which must be one of the

Display blocks are used to select a different indentation and

following arguments:

justification than the one used by the surrounding text.

.Bl -tag -width 12n -offset indent

They may contain both macro lines and free-form text lines.

.It Fl ragged

By default, a display block is preceded by a vertical space.

Only left-justify the block.

.Pp

.It Fl unfilled

The

Do not justify the block at all.

.Ar type

must be one of the following:

.Bl -tag -width 13n -offset indent

.It Fl centered

Centre-justify each line.

Using this display type is not recommended; many

.Nm

implementations render it poorly.

.It Fl filled

Left- and right-justify the block.

.It Fl literal

Alias for

Do not justify the block at all.

.Fl unfilled .

Preserve white space as it appears in the input.

.It Fl centered

.It Fl ragged

Centre-justify each line.

Only left-justify the block.

.It Fl unfilled

An alias for

.Fl literal .

.El

.Pp

The type must be provided first.

The

Secondary arguments are as follows:

.Ar type

.Bl -tag -width 12n -offset indent

must be provided first.

Additional arguments may follow:

.Bl -tag -width 13n -offset indent

.It Fl offset Ar width

Offset by the value of

Indent the display by the

.Ar width ,

which is interpreted as one of the following, specified in order:

which may be one of the following:

.Bl -item

.It

As one of the pre-defined strings

One of the pre-defined strings

.Ar indent ,

.Cm indent ,

the width of standard indentation;

.Ar indent-two ,

.Cm indent-two ,

twice

.Ar indent ;

.Cm indent ;

.Ar left ,

.Cm left ,

which has no effect ;

which has no effect;

.Ar right ,

.Cm right ,

which justifies to the right margin; and

which justifies to the right margin; or

.Ar center ,

.Cm center ,

which aligns around an imagined centre axis.

.It

As a precalculated width for a named macro.

A macro invocation, which selects a predefined width

associated with that macro.

The most popular is the imaginary macro

.Ar \&Ds ,

which resolves to

.Ar 6n .

.Sy 6n .

.It

As a scaling unit following the syntax described in

A width using the syntax described in

.Sx Scaling Widths .

.It

As the calculated string length of the opaque string.

An arbitrary string, which indents by the length of this string.

.El

.Pp

If unset, it will revert to the value of

When the argument is missing,

.Ar 8n

.Fl offset

as described in

is ignored.

.Sx Scaling Widths .

.It Fl compact

Do not assert a vertical space before the block.

Do not assert vertical space before the display.

.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

\&.Bd \-literal \-offset indent \-compact

Hello world.

\&.Ed

.Ed

Line 1118 See also

Line 1137 See also

and

.Sx \&Dl .

.Ss \&Bf

Change the font mode for a scoped block of text.

Its syntax is as follows:

.Bd -ragged -offset indent

.Pf \. Sx \&Bf

.Oo

.Fl emphasis | literal | symbolic |

.Cm \&Em | \&Li | \&Sy

.Oc

.Ed

.Pp

The

.Fl emphasis

and

.Cm \&Em

argument are equivalent, as are

.Fl symbolic

and

.Cm \&Sy ,

and

.Fl literal

and

.Cm \&Li .

Without an argument, this macro does nothing.

The font mode continues until broken by a new font mode in a nested

scope or

.Sx \&Ef

is encountered.

.Pp

See also

.Sx \&Li ,

.Sx \&Ef ,

.Sx \&Em ,

and

.Sx \&Sy .

.Ss \&Bk

Keep the output generated from each macro input line together

on one single output line.

Line breaks in free-form text lines are unaffected.

The syntax is as follows:

.Pp

.D1 Pf \. Sx \&Bk Fl words

.Pp

The

.Fl words

argument is required; additional arguments are ignored.

.Pp

The following example will not break within each

.Sx \&Op

macro line:

.Bd -literal -offset indent

\&.Bk \-words

\&.Op Fl f Ar flags

\&.Op Fl o Ar output

\&.Ek

.Ed

.Pp

Be careful in using over-long lines within a keep block!

Doing so will clobber the right margin.

.Ss \&Bl

Begins a list composed of one or more list entries.

Begin a list.

A list is associated with a type, which is a required argument.

Lists consist of items started by the

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

macro, containing a head or a body or both.

type).

The list syntax is as follows:

.Bd -ragged -offset indent

.Pf \. Sx \&Bl

.Fl Ns Ar type

.Op Fl width Ar val

.Op Fl offset Ar val

.Op Fl compact

.Op HEAD ...

.Ed

.Pp

The list

.Ar type

is mandatory and must be specified first.

The

.Fl width

and

.Fl offset

arguments accept

.Sx Scaling Widths

or use the length of the given string.

The

.Fl offset

is a global indentation for the whole list, affecting both item heads

and bodies.

For those list types supporting it, the

.Fl width

argument requests an additional indentation of item bodies,

to be added to the

.Fl offset .

Unless the

.Fl compact

argument is specified, list entries are separated by vertical space.

.Pp

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.

No item heads can be specified, but a bullet will be printed at the head

The head of list entries must be empty.

of each item.

List entry bodies are positioned after the bullet.

Item bodies start on the same output line as the bullet

The

and are indented according to the

.Fl width

argument varies the width of list bodies' left-margins.

argument.

.It Fl column

A columnated list.

The

.Fl width

argument has no effect.

argument has no effect; instead, each argument specifies the width

The number of columns is specified as parameters to the

of one column, using either the

.Sx \&Bl

macro.

These dictate the width of columns either as

.Sx Scaling Widths

or literal text.

syntax or the string length of the argument.

If the initial macro of a

If the first line of the body of a

.Fl column

list is not an

.Sx \&It ,

.Sx \&It

context spanning each line is implied until an

macro line,

.Sx \&It

line macro is encountered, at which point list bodies are interpreted as

contexts spanning one input line each are implied until an

.Sx \&It

macro line is encountered, at which point items start being interpreted as

described in the

.Sx \&It

documentation.

.It Fl dash

A list offset by a dash (hyphen).

The head of list entries must be empty.

.Fl bullet ,

List entry bodies are positioned past the dash.

except that dashes are used in place of bullets.

The

.Fl width

argument varies the width of list bodies' left-margins.

.It Fl diag

.Fl inset ,

but with additional formatting to the head.

except that item heads are not parsed for macro invocations.

The

.\" but with additional formatting to the head.

.Fl width

argument varies the width of list bodies' left-margins.

.It Fl enum

An enumerated list offset by the enumeration from 1.

A numbered list.

The head of list entries must be empty.

Formatted like

List entry bodies are positioned after the enumeration.

.Fl bullet ,

The

except that cardinal numbers are used in place of bullets,

.Fl width

starting at 1.

argument varies the width of list bodies' left-margins.

.It Fl hang

.Fl tag ,

but instead of list bodies positioned after the head, they trail the

except that the first lines of item bodies are not indented, but follow

head text.

the item heads like in

The

.Fl inset

.Fl width

lists.

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.

Item bodies follow items heads on the same line, using normal inter-word

The

spacing.

Bodies are not indented, and the

.Fl width

argument is ignored.

.It Fl item

This produces blocks of text.

No item heads can be specified, and none are printed.

The head of list entries must be empty.

Bodies are not indented, and the

The

.Fl width

argument is ignored.

.It Fl ohang

List bodies are positioned on the line following the head.

Item bodies start on the line following item heads and are not indented.

The

.Fl width

argument is ignored.

.It Fl tag

A list offset by list entry heads. List entry bodies are positioned

Item bodies are indented according to the

after the head as specified by the

.Fl width

argument.

When an item head fits inside the indentation, the item body follows

this head on the same output line.

Otherwise, the body starts on the output line following the head.

.El

.Pp

See also

.Sx \&El

and

.Sx \&It .

.Ss \&Bo

Begins a block enclosed by square brackets.

Begin a block enclosed by square brackets.

Does not have any head arguments.

.Pp

Examples:

.Bd -literal -offset indent

.Bd -literal -offset indent -compact

\&.Bo 1 ,

\&.Dv BUFSIZ \&Bc

.Ed

Line 1255 and

Line 1345 and

See also

.Sx \&Bo .

.Ss \&Brc

Closes a

Close a

.Sx \&Bro

block. Does not have any tail arguments.

block.

Does not have any tail arguments.

.Ss \&Bro

Begins a block enclosed by curly braces.

Begin a block enclosed by curly braces.

Does not have any head arguments.

.Pp

Examples:

.Bd -literal -offset indent

.Bd -literal -offset indent -compact

\&.Bro 1 , ... ,

\&.Va n \&Brc

.Ed

Line 1297 and

Line 1388 and

.Sx \&Ux .

.Ss \&Bt

Prints

.Dq is currently in beta test.

.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.

Line 1316 See also

Line 1407 See also

and

.Sx \&Ux .

.Ss \&Cd

Configuration declaration.

Kernel configuration declaration.

This denotes strings accepted by

.Xr config 8 .

.Pp

Line 1325 Examples:

Line 1416 Examples:

.Pp

.Em Remarks :

this macro is commonly abused by using quoted literals to retain

white-space and align consecutive

whitespace and align consecutive

.Sx \&Cd

declarations.

This practise is discouraged.

Line 1353 See also

Line 1444 See also

and

.Sx \&Dl .

.Ss \&Db

Start a debugging context.

Switch debugging mode.

This macro is parsed, but generally ignored.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Db Cm on | off

.Pp

This macro is ignored by

.Xr mandoc 1 .

.Ss \&Dc

Closes a

Close a

.Sx \&Do

block. Does not have any tail arguments.

block.

Does not have any tail arguments.

.Ss \&Dd

Document date.

This is the mandatory first macro of any

Line 1369 This is the mandatory first macro of any

Line 1463 This is the mandatory first macro of any

manual.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Dd Cm date

.D1 Pf \. Sx \&Dd Op Ar date

.Pp

The

.Cm date

.Ar date

field may be either

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.

If a date does not conform or is empty, the current date is used.

.Pp

Examples:

.D1 \&.Dd $\&Mdocdate$

Line 1397 invocations.

Line 1491 invocations.

It is followed by a newline.

.Pp

Examples:

.D1 \&.Dl % mandoc mdoc.7 | less

.D1 \&.Dl % mandoc mdoc.7 \e(ba less

.Pp

See also

.Sx \&Bd

and

.Sx \&D1 .

.Ss \&Do

Begins a block enclosed by double quotes. Does not have any head

Begin a block enclosed by double quotes.

arguments.

Does not have any head arguments.

.Pp

Examples:

.D1 \&.D1 \&Do April is the cruellest month \&Dc \e(em T.S. Eliot

.Bd -literal -offset indent -compact

\&.Do

April is the cruellest month

\&.Dc

\e(em T.S. Eliot

.Ed

.Pp

See also

.Sx \&Dq .

.Ss \&Dq

Encloses its arguments in double quotes.

Encloses its arguments in

.Dq typographic

double-quotes.

.Pp

Examples:

.Bd -literal -offset indent -compact

Line 1422 Examples:

Line 1523 Examples:

.Ed

.Pp

See also

.Sx \&Qq ,

.Sx \&Sq ,

and

.Sx \&Do .

.Ss \&Dt

Document title.

Line 1432 Its syntax is as follows:

Line 1536 Its syntax is as follows:

.Bd -ragged -offset indent

.Pf \. Sx \&Dt

.Oo

.Cm title

.Ar title

.Oo

.Cm section

.Ar section

.Op Cm volume | arch

.Op Ar volume | arch

.Oc

.Ed

.Pp

Its arguments are as follows:

.Bl -tag -width Ds -offset Ds

.It Cm title

.It Ar title

The document's title (name), defaulting to

.Qq UNKNOWN

.Dq UNKNOWN

if unspecified.

It should be capitalised.

.It Cm section

.It Ar section

The manual section.

This may be one of

.Ar 1

Line 1484 or

Line 1588 or

.Ar paper

.Pq paper .

It should correspond to the manual's filename suffix and defaults to

.Qq 1

.Dq 1

if unspecified.

.It Cm volume

.It Ar volume

This overrides the volume inferred from

.Ar section .

This field is optional, and if specified, must be one of

Line 1515 This field is optional, and if specified, must be one

Line 1619 This field is optional, and if specified, must be one

.Ar CON

.Pq contributed manuals .

.It Cm arch

.It Ar arch

This specifies a specific relevant architecture.

.Cm volume

.Ar volume

is not provided, it may be used in its place, else it may be used

subsequent that.

It, too, is optional.

Line 1589 See also

Line 1693 See also

and

.Sx \&Ux .

.Ss \&Ec

Close a scope started by

.Sx \&Eo .

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Ec Op Ar TERM

.Pp

The

.Ar TERM

argument is used as the enclosure tail, for example, specifying \e(rq

will emulate

.Sx \&Dc .

.Ss \&Ed

End a display context started by

.Sx \&Bd .

.Ss \&Ef

End a font mode context started by

.Sx \&Bf .

.Ss \&Ek

End a keep context started by

.Sx \&Bk .

.Ss \&El

Ends a list context started by

End a list context started by

.Sx \&Bl .

.Pp

See also

Line 1608 stylistically decorating technical terms.

Line 1729 stylistically decorating technical terms.

Examples:

.D1 \&.Em Warnings!

.D1 \&.Em Remarks :

.Pp

See also

.Sx \&Bf ,

.Sx \&Sy ,

and

.Sx \&Li .

.Ss \&En

This macro is obsolete and not implemented in

.Xr mandoc 1 .

.Ss \&Eo

An arbitrary enclosure.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Eo Op Ar TERM

.Pp

The

.Ar TERM

argument is used as the enclosure head, for example, specifying \e(lq

will emulate

.Sx \&Do .

.Ss \&Er

Display error constants.

.Pp

Line 1620 Examples:

Line 1759 Examples:

See also

.Sx \&Dv .

.Ss \&Es

This macro is obsolete and not implemented.

.Ss \&Ev

Environmental variables such as those specified in

.Xr environ 7 .

Line 1628 Examples:

Line 1768 Examples:

.D1 \&.Ev DISPLAY

.D1 \&.Ev PATH

.Ss \&Ex

Inserts text regarding a utility's exit values.

Insert a standard sentence regarding exit values.

This macro must have first the

Its syntax is as follows:

.Fl std

.Pp

argument specified, then an optional

.D1 Pf \. Sx \&Ex Fl std Op Ar utility

.Ar utility .

.Pp

When

.Ar utility

is not provided, the document's name as stipulated in

is not specified, the document's name set by

.Sx \&Nm

is provided.

is used.

.Pp

See also

.Sx \&Rv .

.Ss \&Fa

Function argument.

Its syntax is as follows:

Line 1670 Examples:

Line 1813 Examples:

See also

.Sx \&Fo .

.Ss \&Fc

End a function context started by

.Sx \&Fo .

.Ss \&Fd

Historically used to document include files.

This usage has been deprecated in favour of

Line 1755 See also

Line 1900 See also

.Sx \&Fa ,

.Sx \&Fc ,

and

.Sx \&Ft .

.Ss \&Ft

A function type.

Its syntax is as follows:

Line 1774 See also

Line 1920 See also

and

.Sx \&Fo .

.Ss \&Fx

Format the FreeBSD version provided as an argument, or a default value

Format the

.Fx

version provided as an argument, or a default value

if no argument is provided.

.Pp

Examples:

Line 1791 See also

Line 1939 See also

and

.Sx \&Ux .

.Ss \&Hf

This macro is obsolete and not implemented.

.Ss \&Ic

Designate an internal or interactive command.

This is similar to

.Sx \&Cm

but used for instructions rather than values.

.Pp

Examples:

.D1 \&.Ic hash

.D1 \&.Ic alias

.Pp

Note that using

.Sx \&Bd Fl literal

.Sx \&D1

is preferred for displaying code; the

.Sx \&Ic

macro is used when referring to specific instructions.

.Ss \&In

.Qq include

.Dq include

file.

In the

.Em SYNOPSIS

section (only if invoked as the line macro), the first argument is

preceded by

.Qq #include ,

.Dq #include ,

the arguments is enclosed in angled braces.

the arguments is enclosed in angle brackets.

.Pp

Examples:

.D1 \&.In sys/types

Line 1872 are interpreted within the scope of the last phrase.

Line 2037 are interpreted within the scope of the last phrase.

Calling the pseudo-macro

.Sq \&Ta

will open a new phrase scope (this must occur on a macro line to be

interpreted as a macro). Note that the tab phrase delimiter may only be

interpreted as a macro).

used within the

Note that the tab phrase delimiter may only be used within the

.Sx \&It

line itself.

Subsequent this, only the

Line 1914 Examples:

Line 2079 Examples:

.D1 \&.Lb libz

.D1 \&.Lb mdoc

.Ss \&Li

Denotes text that should be in a literal font mode.

Note that this is a presentation term and should not be used for

stylistically decorating technical terms.

.Pp

See also

.Sx \&Bf ,

.Sx \&Sy ,

and

.Sx \&Em .

.Ss \&Lk

Format a hyperlink.

Its syntax is as follows:

Line 1921 Its syntax is as follows:

Line 2095 Its syntax is as follows:

.D1 Pf \. Sx \&Lk Cm uri Op Cm name

.Pp

Examples:

.D1 \&.Lk http://bsd.lv "The BSD.lv Project"

.D1 \&.Lk http://bsd.lv \*qThe BSD.lv Project\*q

.D1 \&.Lk http://bsd.lv

.Pp

See also

.Sx \&Mt .

.Ss \&Lp

Synonym for

.Sx \&Pp .

.Ss \&Ms

Display a mathematical symbol.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Ms Cm symbol

.Pp

Examples:

.D1 \&.Ms sigma

.D1 \&.Ms aleph

.Ss \&Mt

Format a

.Qq mailto:

.Dq mailto:

hyperlink.

Its syntax is as follows:

.Pp

Line 1939 Its syntax is as follows:

Line 2123 Its syntax is as follows:

Examples:

.D1 \&.Mt discuss@manpages.bsd.lv

.Ss \&Nd

A one line description of the manual's content.

This may only be invoked in the

.Em SYNOPSIS

section subsequent the

.Sx \&Nm

macro.

.Pp

Examples:

.D1 \&.Sx \&Nd mdoc language reference

.D1 \&.Sx \&Nd format and display UNIX manuals

.Pp

The

.Sx \&Nd

macro technically accepts child macros and terminates with a subsequent

.Sx \&Sh

invocation.

Do not assume this behaviour: some

.Xr whatis 1

database generators are not smart enough to parse more than the line

arguments and will display macros verbatim.

.Pp

See also

.Sx \&Nm .

.Ss \&Nm

The name of the manual page, or \(em in particular in section 1, 6,

and 8 pages \(em of an additional command or feature documented in

the manual page.

When first invoked, the

.Sx \&Nm

macro expects a single argument, the name of the manual page.

Usually, the first invocation happens in the

.Em NAME

section of the page.

The specified name will be remembered and used whenever the macro is

called again without arguments later in the page.

The

.Sx \&Nm

macro uses

.Sx Block full-implicit

semantics when invoked as the first macro on an input line in the

.Em SYNOPSIS

section; otherwise, it uses ordinary

.Sx In-line

semantics.

.Pp

Examples:

.Bd -literal -offset indent

\&.Sh SYNOPSIS

\&.Nm cat

\&.Op Fl benstuv

\&.Op Ar

.Ed

.Pp

In the

.Em SYNOPSIS

of section 2, 3 and 9 manual pages, use the

.Sx \&Fn

macro rather than

.Sx \&Nm

to mark up the name of the manual page.

.Ss \&No

.Dq noop

macro used to terminate prior macro contexts.

.Pp

Examples:

.D1 \&.Sx \&Fl ab \&No cd \&Fl ef

.Ss \&Ns

Suppress a space.

Following invocation, text is interpreted as free-form text until a

macro is encountered.

.Pp

Examples:

.D1 \&.Fl o \&Ns \&Ar output

.Pp

See also

.Sx \&No

and

.Sx \&Sm .

.Ss \&Nx

Format the NetBSD version provided as an argument, or a default value if

Format the

.Nx

version provided as an argument, or a default value if

no argument is provided.

.Pp

Examples:

Line 1960 See also

Line 2222 See also

and

.Sx \&Ux .

.Ss \&Oc

Close multi-line

.Sx \&Oo

context.

.Ss \&Oo

Multi-line version of

.Sx \&Op .

.Pp

Examples:

.Bd -literal -offset indent -compact

\&.Oo

\&.Op Fl flag Ns Ar value

\&.Oc

.Ed

.Ss \&Op

Command-line option.

Used when listing options to command-line utilities.

Prints the argument(s) in brackets.

.Pp

Examples:

.D1 \&.Op \&Fl a \&Ar b

.D1 \&.Op \&Ar a | b

.Pp

See also

.Sx \&Oo .

.Ss \&Os

Document operating system version.

This is the mandatory third macro of

Line 1970 any

Line 2254 any

file.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Os Op Cm system

.D1 Pf \. Sx \&Os Op Cm system Op Cm version

.Pp

The optional

.Cm system

Line 1993 Unknown usage.

Line 2277 Unknown usage.

.Em Remarks :

this macro has been deprecated.

.Ss \&Ox

Format the OpenBSD version provided as an argument, or a default value

Format the

.Ox

version provided as an argument, or a default value

if no argument is provided.

.Pp

Examples:

Line 2010 See also

Line 2296 See also

and

.Sx \&Ux .

.Ss \&Pa

A file-system path.

.Pp

Examples:

.D1 \&.Pa /usr/bin/mandoc

.D1 \&.Pa /usr/share/man/man7/mdoc.7

.Pp

See also

.Sx \&Lk .

.Ss \&Pc

Close parenthesised context opened by

.Sx \&Po .

.Ss \&Pf

Removes the space

.Pq Dq prefix

between its arguments.

Its syntax is as follows:

.Pp

.D1 Pf \. \&Pf Cm prefix suffix

.Pp

The

.Cm suffix

argument may be a macro.

.Pp

Examples:

.D1 \&.Pf \e. \&Sx \&Pf \&Cm prefix suffix

.Ss \&Po

Multi-line version of

.Sx \&Pq .

.Ss \&Pp

Break a paragraph.

This will assert vertical space between prior and subsequent macros

and/or text.

.Ss \&Pq

Parenthesised enclosure.

.Pp

See also

.Sx \&Po .

.Ss \&Qc

Close quoted context opened by

.Sx \&Qo .

.Ss \&Ql

Format a single-quoted literal.

See also

.Sx \&Qq

and

.Sx \&Sq .

.Ss \&Qo

Multi-line version of

.Sx \&Qq .

.Ss \&Qq

Encloses its arguments in

.Dq typewriter

double-quotes.

Consider using

.Sx \&Dq .

.Pp

See also

.Sx \&Dq ,

.Sx \&Sq ,

and

.Sx \&Qo .

.Ss \&Re

Closes a

Close an

.Sx \&Rs

block.

Does not have any tail arguments.

.Ss \&Rs

Begins a bibliographic

Begin a bibliographic

.Pq Dq reference

block.

Does not have any head arguments.

Line 2065 block is used within a SEE ALSO section, a vertical sp

Line 2403 block is used within a SEE ALSO section, a vertical sp

before the rendered output, else the block continues on the current

line.

.Ss \&Rv

Inserts text regarding a function call's return value.

This macro must consist of the

.Fl std

argument followed by an optional

.Ar function .

.Ar function

is not provided, the document's name as stipulated by the first

.Sx \&Nm

is provided.

.Pp

See also

.Sx \&Ex .

.Ss \&Sc

Close single-quoted context opened by

.Sx \&So .

.Ss \&Sh

Begin a new section.

For a list of conventional manual sections, see

.Sx MANUAL STRUCTURE .

These sections should be used unless it's absolutely necessary that

custom sections be used.

.Pp

Section names should be unique so that they may be keyed by

.Sx \&Sx .

.Pp

See also

.Sx \&Pp ,

.Sx \&Ss ,

and

.Sx \&Sx .

.Ss \&Sm

Switches the spacing mode for output generated from macros.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&Sm Cm on | off

.Pp

By default, spacing is

.Cm on .

When switched

.Cm off ,

no white space is inserted between macro arguments and between the

output generated from adjacent macros, but free-form text lines

still get normal spacing between words and sentences.

.Ss \&So

Multi-line version of

.Sx \&Sq .

.Ss \&Sq

Encloses its arguments in

.Dq typewriter

single-quotes.

.Pp

See also

.Sx \&Dq ,

.Sx \&Qq ,

and

.Sx \&So .

.Ss \&Ss

Begin a new sub-section.

Unlike with

.Sx \&Sh ,

there's no convention for sub-sections.

Conventional sections, as described in

.Sx MANUAL STRUCTURE ,

rarely have sub-sections.

.Pp

Sub-section names should be unique so that they may be keyed by

.Sx \&Sx .

.Pp

See also

.Sx \&Pp ,

.Sx \&Sh ,

and

.Sx \&Sx .

.Ss \&St

Replace an abbreviation for a standard with the full form.

The following standards are recognised:

.Pp

.Bl -tag -width "-p1003.1g-2000X" -compact

.It \-p1003.1-88

.St -p1003.1-88

.It \-p1003.1-90

.St -p1003.1-90

.It \-p1003.1-96

.St -p1003.1-96

.It \-p1003.1-2001

.St -p1003.1-2001

.It \-p1003.1-2004

.St -p1003.1-2004

.It \-p1003.1-2008

.St -p1003.1-2008

.It \-p1003.1

.St -p1003.1

.It \-p1003.1b

.St -p1003.1b

.It \-p1003.1b-93

.St -p1003.1b-93

.It \-p1003.1c-95

.St -p1003.1c-95

.It \-p1003.1g-2000

.St -p1003.1g-2000

.It \-p1003.1i-95

.St -p1003.1i-95

.It \-p1003.2-92

.St -p1003.2-92

.It \-p1003.2a-92

.St -p1003.2a-92

.It \-p1387.2-95

.St -p1387.2-95

.It \-p1003.2

.St -p1003.2

.It \-p1387.2

.St -p1387.2

.It \-isoC

.St -isoC

.It \-isoC-90

.St -isoC-90

.It \-isoC-amd1

.St -isoC-amd1

.It \-isoC-tcor1

.St -isoC-tcor1

.It \-isoC-tcor2

.St -isoC-tcor2

.It \-isoC-99

.St -isoC-99

.It \-iso9945-1-90

.St -iso9945-1-90

.It \-iso9945-1-96

.St -iso9945-1-96

.It \-iso9945-2-93

.St -iso9945-2-93

.It \-ansiC

.St -ansiC

.It \-ansiC-89

.St -ansiC-89

.It \-ansiC-99

.St -ansiC-99

.It \-ieee754

.St -ieee754

.It \-iso8802-3

.St -iso8802-3

.It \-ieee1275-94

.St -ieee1275-94

.It \-xpg3

.St -xpg3

.It \-xpg4

.St -xpg4

.It \-xpg4.2

.St -xpg4.2

.St -xpg4.3

.It \-xbd5

.St -xbd5

.It \-xcu5

.St -xcu5

.It \-xsh5

.St -xsh5

.It \-xns5

.St -xns5

.It \-xns5.2

.St -xns5.2

.It \-xns5.2d2.0

.St -xns5.2d2.0

.It \-xcurses4.2

.St -xcurses4.2

.It \-susv2

.St -susv2

.It \-susv3

.St -susv3

.It \-svid4

.St -svid4

.El

.Ss \&Sx

Reference a section or sub-section.

The referenced section or sub-section name must be identical to the

enclosed argument, including whitespace.

.Pp

Examples:

.D1 \&.Sx MANUAL STRUCTURE

.Ss \&Sy

Format enclosed arguments in symbolic

.Pq Dq boldface .

Note that this is a presentation term and should not be used for

stylistically decorating technical terms.

.Pp

See also

.Sx \&Bf ,

.Sx \&Li ,

and

.Sx \&Em .

.Ss \&Tn

Format a tradename.

.Pp

Examples:

.D1 \&.Tn IBM

.Ss \&Ud

Prints out

.Dq currently under development.

.Dq currently under development .

.Ss \&Ux

Format the UNIX name.

Accepts no argument.

Line 2095 See also

Line 2617 See also

and

.Sx \&Ox .

.Ss \&Va

A variable name.

.Pp

Examples:

.D1 \&.Va foo

.D1 \&.Va const char *bar ;

.Ss \&Vt

A variable type.

This is also used for indicating global variables in the

Line 2145 is followed by non-punctuation, an

Line 2672 is followed by non-punctuation, an

.Sx \&Ns

is inserted into the token stream.

This behaviour is for compatibility with

.Xr groff 1 .

GNU troff.

.Pp

Examples:

.D1 \&.Xr mandoc 1

.D1 \&.Xr mandoc 1 \&;

.D1 \&.Xr mandoc 1 \&Ns s behaviour

.Ss \&br

Emits a line-break.

This macro should not be used; it is implemented for compatibility with

historical manuals.

.Pp

Consider using

.Sx \&Pp

in the event of natural paragraph breaks.

.Ss \&sp

Emits vertical space.

This macro should not be used; it is implemented for compatibility with

historical manuals.

Its syntax is as follows:

.Pp

.D1 Pf \. Sx \&sp Op Cm height

.Pp

The

.Cm height

argument must be formatted as described in

.Sx Scaling Widths .

If unspecified,

.Sx \&sp

asserts a single vertical space.

.Sh COMPATIBILITY

This section documents compatibility between mandoc and other other

troff implementations, at this time limited to GNU troff

Line 2167 file re-write

Line 2715 file re-write

Heirloom troff, the other significant troff implementation accepting

\-mdoc, is similar to historic groff.

.Pp

The following problematic behaviour is found in groff:

.ds hist (Historic groff only.)

.Pp

.Bl -dash -compact

.It

groff supports a

.Sx \&At

.Fl file Ar filename

with unknown arguments produces no output at all.

argument to

\*[hist]

.Sx \&Bd .

Newer groff and mandoc print

mandoc does not.

.Qq AT&T UNIX

and the arguments.

.It

groff behaves inconsistently when encountering

.Sx \&Bd Fl column

.Pf non- Sx \&Fa

does not recognize trailing punctuation characters when they immediately

children of

precede tabulator characters, but treats them as normal text and

outputs a space before them.

.It

.Sx \&Bd Fl ragged compact

does not start a new line.

\*[hist]

.It

.Sx \&Dd

without an argument prints

.Dq Epoch .

In mandoc, it resolves to the current date.

.It

.Sx \&Fl

does not print a dash for an empty argument.

\*[hist]

.It

.Sx \&Fn

does not start a new line unless invoked as the line macro in the

.Em SYNOPSIS

section.

\*[hist]

.It

.Sx \&Fo

regarding spacing between arguments.

with

In mandoc, this is not the case: each argument is consistently followed

.Pf non- Sx \&Fa

by a single space and the trailing

children causes inconsistent spacing between arguments.

.Sq \&)

In mandoc, a single space is always inserted between arguments.

suppresses prior spacing.

.It

groff behaves inconsistently when encountering

.Sx \&Ft

and

.Sx \&Fn

in the

.Em SYNOPSIS :

.Em SYNOPSIS

at times newline(s) are suppressed depending on whether a prior

causes inconsistent vertical spacing, depending on whether a prior

.Sx \&Fn

has been invoked.

In mandoc, this is not the case.

See

.Sx \&Ft

and

.Sx \&Fn

for the normalised behaviour.

for the normalised behaviour in mandoc.

.It

Historic groff does not break before an

.Sx \&Fn

when not invoked as the line macro in the

.Em SYNOPSIS

section.

.It

Historic groff formats the

.Sx \&In

badly: trailing arguments are trashed and

ignores additional arguments and is not treated specially in the

.Em SYNOPSIS

.Em SYNOPSIS .

is not specially treated.

\*[hist]

.It

groff does not accept the

.Sx \&It

.Sq \&Ta

sometimes requires a

pseudo-macro as a line macro.

.Fl nested

mandoc does.

flag.

\*[hist]

In new groff and mandoc, any list may be nested by default and

.Fl enum

lists will restart the sequence only for the sub-list.

.It

The comment syntax

.Sx \&Li

.Sq \e."

followed by a reserved character is incorrectly used in some manuals

is no longer accepted.

instead of properly quoting that character, which sometimes works with

historic groff.

.It

In groff, the

.Sx \&Lk

only accepts a single link-name argument; the remainder is misformatted.

.It

.Sx \&Pa

macro does not format its arguments when used in the FILES section under

does not format its arguments when used in the FILES section under

certain list types.

mandoc does.

.It

Historic groff does not print a dash for empty

.Sx \&Ta

.Sx \&Fl

can only be called by other macros, but not at the beginning of a line.

arguments.

mandoc and newer groff implementations do.

.It

groff behaves irregularly when specifying

.Sx \&%C

is not implemented.

.It

Historic groff has many un-callable macros.

Most of these (excluding some block-level macros) are callable

in new groff and mandoc.

.It

.Sq \(ba

(vertical bar) is not fully supported as a delimiter.

\*[hist]

.It

.Sq \ef

.Pq font face

and

.Sq \ef

.Pq font family face

.Sx Text Decoration

within line-macro scopes.

escapes behave irregularly when specified within line-macro scopes.

mandoc follows a consistent system.

.It

In mandoc, negative scaling units are truncated to zero; groff would

Negative scaling units return to prior lines.

move to prior lines.

Instead, mandoc truncates them to zero.

Furthermore, the

.El

.Sq f

.Pp

scaling unit, while accepted, is rendered as the default unit.

The following features are unimplemented in mandoc:

.Pp

.Bl -dash -compact

.It

In quoted literals, groff allowed pair-wise double-quotes to produce a

.Sx \&Bd

standalone double-quote in formatted output.

.Fl file Ar file .

This idiosyncratic behaviour is not applicable in mandoc.

.It

Display types

.Sx \&Bd

.Fl center

.Fl offset Ar center

and

.Fl right

.Fl offset Ar right .

are aliases for

Groff does not implement centered and flush-right rendering either,

.Fl left

but produces large indentations.

in mandoc. 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

Historic groff has many un-callable macros.

The

Most of these (excluding some block-level macros) are now callable.

.Sq \eh

.It

.Pq horizontal position ,

The vertical bar

.Sq \ev

.Sq \(ba

.Pq vertical position ,

made historic groff

.Sq \em

.Qq go orbital

.Pq text colour ,

but has been a proper delimiter since then.

.Sq \eM

.It

.Pq text filling colour ,

.Sx \&It Fl nested

.Sq \ez

is assumed for all lists (it wasn't in historic groff): any list may be

.Pq zero-length character ,

nested and

.Sq \ew

.Fl enum

.Pq string length ,

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

In groff, the

.Sx \&Cd ,

.Sx \&Er ,

.Sx \&Ex ,

and

.Sx \&Rv

.Sq \es

macros were stipulated only to occur in certain manual sections.

.Pq text size

mandoc does not have these restrictions.

escape sequences are all discarded in mandoc.

.It

Newer groff and mandoc print

The

.Qq AT&T UNIX

.Sq \ef

prior to unknown arguments of

scaling unit is accepted by mandoc, but rendered as the default unit.

.Sx \&At ;

.It

older groff did nothing.

In quoted literals, groff allows pairwise double-quotes to produce a

standalone double-quote in formatted output.

This is not supported by mandoc.

.El

.Sh SEE ALSO

.Xr mandoc 1 ,

.Xr mandoc_char 7

.Sh HISTORY

The

.Nm

language first appeared as a troff macro package in

.Bx 4.4 .

It was later significantly updated by Werner Lemberg and Ruslan Ermilov

in groff-1.20.1.

The standalone implementation that is part of the

.Xr mandoc 1

utility written by Kristaps Dzonsons appeared in

.Ox 4.6 .

.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

.\" .

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