xref: /illumos-gate/usr/src/man/man7/mdoc.7 (revision 763f1f5f97e4c16840af2ced98915f0ed0f46616)
1.\"	$Id: mdoc.7,v 1.287 2021/07/29 17:32:01 schwarze Exp $
2.\"
3.\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4.\" Copyright (c) 2010, 2011, 2013-2020 Ingo Schwarze <schwarze@openbsd.org>
5.\"
6.\" Permission to use, copy, modify, and distribute this software for any
7.\" purpose with or without fee is hereby granted, provided that the above
8.\" copyright notice and this permission notice appear in all copies.
9.\"
10.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17.\"
18.\"
19.\" Copyright 2014 Garrett D'Amore <garrett@damore.org>
20.\" Copyright 2018 Nexenta Systems, Inc.
21.\"
22.Dd March 30, 2022
23.Dt MDOC 7
24.Os
25.Sh NAME
26.Nm mdoc
27.Nd semantic markup language for formatting manual pages
28.Sh DESCRIPTION
29The
30.Nm mdoc
31language supports authoring of manual pages for the
32.Xr man 1
33utility by allowing semantic annotations of words, phrases,
34page sections and complete manual pages.
35Such annotations are used by formatting tools to achieve a uniform
36presentation across all manuals written in
37.Nm ,
38and to support hyperlinking if supported by the output medium.
39.Pp
40This reference document describes the structure of manual pages
41and the syntax and usage of the
42.Nm
43language.
44The reference implementation of a parsing and formatting tool is
45.Xr mandoc 1 ;
46the
47.Sx COMPATIBILITY
48section describes compatibility with other implementations.
49.Pp
50In an
51.Nm
52document, lines beginning with the control character
53.Sq \&.
54are called
55.Dq macro lines .
56The first word is the macro name.
57It consists of two or three letters.
58Most macro names begin with a capital letter.
59For a list of available macros, see
60.Sx MACRO OVERVIEW .
61The words following the macro name are arguments to the macro, optionally
62including the names of other, callable macros; see
63.Sx MACRO SYNTAX
64for details.
65.Pp
66Lines not beginning with the control character are called
67.Dq text lines .
68They provide free-form text to be printed; the formatting of the text
69depends on the respective processing context:
70.Bd -literal -offset indent
71\&.Sh Macro lines change control state.
72Text lines are interpreted within the current state.
73.Ed
74.Pp
75Many aspects of the basic syntax of the
76.Nm
77language are based on the
78.Xr mandoc_roff 7
79language; see the
80.Em LANGUAGE SYNTAX
81and
82.Em MACRO SYNTAX
83sections in the
84.Xr mandoc_roff 7
85manual for details, in particular regarding
86comments, escape sequences, whitespace, and quoting.
87However, using
88.Xr mandoc_roff 7
89requests in
90.Nm
91documents is discouraged;
92.Xr mandoc 1
93supports some of them merely for backward compatibility.
94.Sh MANUAL STRUCTURE
95A well-formed
96.Nm
97document consists of a document prologue followed by one or more
98sections.
99.Pp
100The prologue, which consists of the
101.Ic \&Dd ,
102.Ic \&Dt ,
103and
104.Ic \&Os
105macros in that order, is required for every document.
106.Pp
107The first section (sections are denoted by
108.Ic \&Sh )
109must be the NAME section, consisting of at least one
110.Ic \&Nm
111followed by
112.Ic \&Nd .
113.Pp
114Following that, convention dictates specifying at least the
115.Em SYNOPSIS
116and
117.Em DESCRIPTION
118sections, although this varies between manual sections.
119.Pp
120The following is a well-formed skeleton
121.Nm
122file for a utility
123.Qq progname :
124.Bd -literal -offset indent
125\&.Dd Jan 1, 1970
126\&.Dt PROGNAME section
127\&.Os
128\&.Sh NAME
129\&.Nm progname
130\&.Nd one line about what it does
131\&.\e\(dq .Sh LIBRARY
132\&.\e\(dq For sections 2, 3, and 9 only.
133\&.Sh SYNOPSIS
134\&.Nm progname
135\&.Op Fl options
136\&.Ar
137\&.Sh DESCRIPTION
138The
139\&.Nm
140utility processes files ...
141\&.\e\(dq .Sh IMPLEMENTATION NOTES
142\&.\e\(dq .Sh RETURN VALUES
143\&.\e\(dq For sections 2, 3, 7, and 9 only.
144\&.\e\(dq .Sh CONTEXT
145\&.\e\(dq For section 9 functions only.
146\&.\e\(dq .Sh ENVIRONMENT
147\&.\e\(dq For sections 1, 7, and 8.
148\&.\e\(dq .Sh FILES
149\&.\e\(dq .Sh EXIT STATUS
150\&.\e\(dq For sections 1, 7, and 8.
151\&.\e\(dq .Sh EXAMPLES
152\&.\e\(dq .Sh DIAGNOSTICS
153\&.\e\(dq .Sh ERRORS
154\&.\e\(dq For sections 2, 3, 4, and 9 only.
155\&.\e\(dq .Sh ARCHITECTURE
156\&.\e\(dq .Sh CODE SET INDEPENDENCE
157\&.\e\(dq For sections 1, 3, and 8 only.
158\&.\e\(dq .Sh INTERFACE STABILITY
159\&.\e\(dq .Sh MT-LEVEL
160\&.\e\(dq For sections 2 and 3 only.
161\&.\e\(dq .Sh SECURITY
162\&.\e\(dq .Sh SEE ALSO
163\&.\e\(dq .Xr foobar 1
164\&.\e\(dq .Sh STANDARDS
165\&.\e\(dq .Sh HISTORY
166\&.\e\(dq .Sh AUTHORS
167\&.\e\(dq .Sh CAVEATS
168\&.\e\(dq .Sh BUGS
169.Ed
170.Pp
171The sections in an
172.Nm
173document are conventionally ordered as they appear above.
174Sections should be composed as follows:
175.Bl -ohang -offset Ds
176.It Em NAME
177The name(s) and a one line description of the documented material.
178The syntax for this as follows:
179.Bd -literal -offset indent
180\&.Nm name0 ,
181\&.Nm name1 ,
182\&.Nm name2
183\&.Nd a one line description
184.Ed
185.Pp
186Multiple
187.Sq \&Nm
188names should be separated by commas.
189.Pp
190The
191.Ic \&Nm
192macro(s) must precede the
193.Ic \&Nd
194macro.
195.Pp
196See
197.Ic \&Nm
198and
199.Ic \&Nd .
200.It Em LIBRARY
201The name of the library containing the documented material, which is
202assumed to be a function in a section 2, 3, or 9 manual.
203The syntax for this is as follows:
204.Bd -literal -offset indent
205\&.Lb libarm
206.Ed
207.Pp
208See
209.Ic \&Lb .
210.It Em SYNOPSIS
211Documents the utility invocation syntax, function call syntax, or device
212configuration.
213.Pp
214For the first, utilities (sections 1 and 8), this is
215generally structured as follows:
216.Bd -literal -offset indent
217\&.Nm bar
218\&.Op Fl v
219\&.Op Fl o Ar file
220\&.Op Ar
221\&.Nm foo
222\&.Op Fl v
223\&.Op Fl o Ar file
224\&.Op Ar
225.Ed
226.Pp
227Commands should be ordered alphabetically.
228.Pp
229For the second, function calls (sections 2, 3, 4I, 4P, 9):
230.Bd -literal -offset indent
231\&.In header.h
232\&.Vt extern const char *global;
233\&.Ft "char *"
234\&.Fn foo "const char *src"
235\&.Ft "char *"
236\&.Fn bar "const char *src"
237.Ed
238.Pp
239Ordering of
240.Ic \&In ,
241.Ic \&Vt ,
242.Ic \&Fn ,
243and
244.Ic \&Fo
245macros should follow C header-file conventions.
246.Pp
247And for the third, configurations (section 4D):
248.Bd -literal -offset indent
249\&.Pa /dev/device_node
250.Ed
251.Pp
252Manuals not in these sections generally don't need a
253.Em SYNOPSIS .
254.Pp
255Some macros are displayed differently in the
256.Em SYNOPSIS
257section, particularly
258.Ic \&Nm ,
259.Ic \&Cd ,
260.Ic \&Fd ,
261.Ic \&Fn ,
262.Ic \&Fo ,
263.Ic \&In ,
264.Ic \&Vt ,
265and
266.Ic \&Ft .
267All of these macros are output on their own line.
268If two such dissimilar macros are pairwise invoked (except for
269.Ic \&Ft
270before
271.Ic \&Fo
272or
273.Ic \&Fn ) ,
274they are separated by a vertical space, unless in the case of
275.Ic \&Fo ,
276.Ic \&Fn ,
277and
278.Ic \&Ft ,
279which are always separated by vertical space.
280.Pp
281When text and macros following an
282.Ic \&Nm
283macro starting an input line span multiple output lines,
284all output lines but the first will be indented to align
285with the text immediately following the
286.Ic \&Nm
287macro, up to the next
288.Ic \&Nm ,
289.Ic \&Sh ,
290or
291.Ic \&Ss
292macro or the end of an enclosing block, whichever comes first.
293.It Em DESCRIPTION
294This begins with an expansion of the brief, one line description in
295.Em NAME :
296.Bd -literal -offset indent
297The
298\&.Nm
299utility does this, that, and the other.
300.Ed
301.Pp
302It usually follows with a breakdown of the options (if documenting a
303command), such as:
304.Bd -literal -offset indent
305The options are as follows:
306\&.Bl \-tag \-width Ds
307\&.It Fl v
308Print verbose information.
309\&.El
310.Ed
311.Pp
312List the options in alphabetical order,
313uppercase before lowercase for each letter and
314with no regard to whether an option takes an argument.
315Put digits in ascending order before all letter options.
316.Pp
317Manuals not documenting a command won't include the above fragment.
318.Pp
319Since the
320.Em DESCRIPTION
321section usually contains most of the text of a manual, longer manuals
322often use the
323.Ic \&Ss
324macro to form subsections.
325In very long manuals, the
326.Em DESCRIPTION
327may be split into multiple sections, each started by an
328.Ic \&Sh
329macro followed by a non-standard section name, and each having
330several subsections, like in the present
331.Nm
332manual.
333.It Em IMPLEMENTATION NOTES
334Implementation-specific notes should be kept here.
335This is useful when implementing standard functions that may have side
336effects or notable algorithmic implications.
337.It Em RETURN VALUES
338This section documents the
339return values of functions in sections 2, 3, and 9.
340.Pp
341See
342.Ic \&Rv .
343.It Em CONTEXT
344This section lists the contexts in which functions can be called in section 9.
345The contexts are user, kernel, or interrupt.
346.It Em ENVIRONMENT
347Lists the environment variables used by the utility,
348and explains the syntax and semantics of their values.
349The
350.Xr environ 7
351manual provides examples of typical content and formatting.
352.Pp
353See
354.Ic \&Ev .
355.It Em FILES
356Documents files used.
357It's helpful to document both the file name and a short description of how
358the file is used (created, modified, etc.).
359.Pp
360See
361.Ic \&Pa .
362.It Em EXIT STATUS
363This section documents the
364command exit status for sections 1 and 8.
365Historically, this information was described in
366.Em DIAGNOSTICS ,
367a practise that is now discouraged.
368.Pp
369See
370.Ic \&Ex .
371.It Em EXAMPLES
372Example usages.
373This often contains snippets of well-formed, well-tested invocations.
374Make sure that examples work properly!
375.It Em DIAGNOSTICS
376Documents error and diagnostic messages displayed to the user or
377sent to logs.
378Note that exit status and return values should be documented in the
379.Em EXIT STATUS
380and
381.Em RETURN VALUES
382sections.
383.Pp
384See
385.Ic \&Bl
386.Fl diag .
387.It Em ERRORS
388Documents error handling in sections 2, 3, 7, and 9.
389.Pp
390See
391.Ic \&Er .
392.It Em ARCHITECTURE
393This section is usually absent, but will be present when the
394interface is specific to one or more architectures.
395.It Em CODE SET INDEPENDENCE
396Indicates whether the interface operates correctly with various different
397code sets.
398True independent code sets will support not only ASCII and Extended UNIX
399Codesets (EUC), but also other multi-byte encodings such as UTF-8 and GB2312.
400.Pp
401Generally there will be some limitations that are fairly standard.
402See
403.Xr standards 7
404for more information about some of these.
405Most interfaces should support at least UTF-8 in addition to ASCII.
406.It Em INTERFACE STABILITY
407Indicates the level of commitment to the interface.
408Interfaces can be described with in the following ways:
409.Bl -tag -width Ds
410.It Nm Standard
411Indicates that the interface is defined by one or more standards bodies.
412Generally, changes to the interface will be carefully managed to conform
413to the relevant standards.
414These interfaces are generally the most suitable for use in portable programs.
415.It Nm Committed
416Indicates that the interface is intended to be preserved for the long-haul, and
417will rarely, if ever change, and never without notification (barring
418extraordinary and extenuating circumstances).
419These interfaces are preferred over other interfaces with the exception of
420.Nm Standard
421interfaces.
422.It Nm Uncommitted
423Indicates that the interface may change.
424Generally, changes to these interfaces should be infrequent, and some effort
425will be made to address compatibility considerations when changing or removing
426such interfaces.
427However, there is no firm commitment to the preservation of the interface.
428Most often this is applied to interfaces where operational experience with the
429interface is still limited and some need to change may be anticipated.
430.Pp
431Consumers should expect to revalidate any
432.Nm Uncommitted
433interfaces when crossing release boundaries.
434Products intended for use on many releases or intended to support compatibility
435with future releases should avoid these interfaces.
436.It Nm Volatile
437The interface can change at any time for any reason.
438Often this relates to interfaces that are part of external software components
439that are still evolving rapidly.
440Consumers should not expect that the interface (either binary or source level)
441will be unchanged from one release to the next.
442.It Nm Not-an-Interface
443Describes something that is specifically not intended for programmatic
444consumption.
445For example, specific human-readable output, or the layout of graphical items on
446a user interface, may be described this way.
447Generally programmatic alternatives to these will be available, and should be
448used when programmatic consumption is needed.
449.It Nm Private
450This is an internal interface.
451Generally these interfaces should only be used within the project, and should
452not be used by other programs or modules.
453The interface can and will change without notice as the project needs, at any
454time.
455.Pp
456Most often, Private interfaces will lack any documentation whatsoever, and
457generally any undocumented interface can be assumed to be Private.
458.It Nm Obsolete
459The interface is not intended for use in new projects or programs, and may
460be removed at a future date.
461The
462.Nm Obsolete
463word is a modifier that can
464be applied to other commitment levels.
465For example an
466.Nm Obsolete Committed
467interface is unlikely to be removed or changed, but nonetheless new use
468is discouraged (perhaps a better newer alternative is present).
469.El
470.It Em MT-LEVEL
471This section describes considerations for the interface when used within
472programs that use multiple threads.
473More discussion of these considerations is made in the MT-Level section of
474.Xr attributes 7 .
475The interface can be described in the following ways.
476.Bl -tag -width Ds
477.It Nm Safe
478Indicates the interface is safe for use within multiple threads.
479There may be additional caveats that apply, in which case those will be
480described.
481Note that some interfaces have semantics which may affect other threads, but
482these should be an intrinsic part of the interface rather than an unexpected
483side effect.
484For example, closing a file in one thread will cause that file to be closed in
485all threads.
486.It Nm Unsafe
487Indicates the interface is unsuitable for concurrent use within multiple
488threads.
489A threaded application may still make use of the interface, but will be required
490to provide external synchronization means to ensure that only a single thread
491calls the interface at a time.
492.It Nm MT-Safe
493Indicates that the interface is not only safe for concurrent use, but is
494designed for such use.
495For example, a
496.Nm Safe
497interface may make use of a global lock to provide safety, but at reduced
498internal concurrency, whereas an
499.Nm MT-Safe
500interface will be designed to be efficient even when used concurrently.
501.It Nm Async-Signal-Safe
502Indicates that the library is safe for use within a signal handler.
503An
504.Nm MT-Safe
505interface can be made
506.Nm Async-Signal-Safe
507by ensuring that it blocks signals when acquiring locks.
508.It Nm Safe with Exceptions
509As for
510.Nm Safe
511but with specific exceptions noted.
512.It Nm MT-Safe with Exceptions
513As for
514.Nm MT-Safe
515but with specific exceptions noted.
516.El
517.It Em SECURITY
518Documents any security precautions that operators should consider.
519.It Em SEE ALSO
520References other manuals with related topics.
521This section should exist for most manuals.
522Cross-references should conventionally be ordered first by section, then
523alphabetically (ignoring case).
524.Pp
525References to other documentation concerning the topic of the manual page,
526for example authoritative books or journal articles, may also be
527provided in this section.
528.Pp
529See
530.Ic \&Rs
531and
532.Ic \&Xr .
533.It Em STANDARDS
534References any standards implemented or used.
535If not adhering to any standards, the
536.Em HISTORY
537section should be used instead.
538.Pp
539See
540.Ic \&St .
541.It Em HISTORY
542A brief history of the subject, including where it was first implemented,
543and when it was ported to or reimplemented for the operating system at hand.
544.It Em AUTHORS
545Credits to the person or persons who wrote the code and/or documentation.
546Authors should generally be noted by both name and email address.
547.Pp
548See
549.Ic \&An .
550.It Em CAVEATS
551Common misuses and misunderstandings should be explained
552in this section.
553.It Em BUGS
554Known bugs, limitations, and work-arounds should be described
555in this section.
556.El
557.Sh MACRO OVERVIEW
558This overview is sorted such that macros of similar purpose are listed
559together, to help find the best macro for any given purpose.
560Deprecated macros are not included in the overview, but can be found below
561in the alphabetical
562.Sx MACRO REFERENCE .
563.Ss Document preamble and NAME section macros
564.Bl -column "Brq, Bro, Brc" description
565.It Ic \&Dd Ta document date: Cm $\&Mdocdate$ | Ar month day , year
566.It Ic \&Dt Ta document title: Ar TITLE section Op Ar arch
567.It Ic \&Os Ta operating system version: Op Ar system Op Ar version
568.It Ic \&Nm Ta document name (one argument)
569.It Ic \&Nd Ta document description (one line)
570.El
571.Ss Sections and cross references
572.Bl -column "Brq, Bro, Brc" description
573.It Ic \&Sh Ta section header (one line)
574.It Ic \&Ss Ta subsection header (one line)
575.It Ic \&Sx Ta internal cross reference to a section or subsection
576.It Ic \&Xr Ta cross reference to another manual page: Ar name section
577.It Ic \&Tg Ta tag the definition of a Ar term Pq <= 1 arguments
578.It Ic \&Pp Ta start a text paragraph (no arguments)
579.El
580.Ss Displays and lists
581.Bl -column "Brq, Bro, Brc" description
582.It Ic \&Bd , \&Ed Ta display block:
583.Fl Ar type
584.Op Fl offset Ar width
585.Op Fl compact
586.It Ic \&D1 Ta indented display (one line)
587.It Ic \&Dl Ta indented literal display (one line)
588.It Ic \&Ql Ta in-line literal display: Ql text
589.It Ic \&Bl , \&El Ta list block:
590.Fl Ar type
591.Op Fl width Ar val
592.Op Fl offset Ar val
593.Op Fl compact
594.It Ic \&It Ta list item (syntax depends on Fl Ar type )
595.It Ic \&Ta Ta table cell separator in Ic \&Bl Fl column No lists
596.It Ic \&Rs , \&%* , \&Re Ta bibliographic block (references)
597.El
598.Ss Spacing control
599.Bl -column "Brq, Bro, Brc" description
600.It Ic \&Pf Ta prefix, no following horizontal space (one argument)
601.It Ic \&Ns Ta roman font, no preceding horizontal space (no arguments)
602.It Ic \&Ap Ta apostrophe without surrounding whitespace (no arguments)
603.It Ic \&Sm Ta switch horizontal spacing mode: Op Cm on | off
604.It Ic \&Bk , \&Ek Ta keep block: Fl words
605.El
606.Ss Semantic markup for command line utilities
607.Bl -column "Brq, Bro, Brc" description
608.It Ic \&Nm Ta start a SYNOPSIS block with the name of a utility
609.It Ic \&Fl Ta command line options (flags) (>=0 arguments)
610.It Ic \&Cm Ta command modifier (>0 arguments)
611.It Ic \&Ar Ta command arguments (>=0 arguments)
612.It Ic \&Op , \&Oo , \&Oc Ta optional syntax elements (enclosure)
613.It Ic \&Ic Ta internal or interactive command (>0 arguments)
614.It Ic \&Ev Ta environmental variable (>0 arguments)
615.It Ic \&Pa Ta file system path (>=0 arguments)
616.El
617.Ss Semantic markup for function libraries
618.Bl -column "Brq, Bro, Brc" description
619.It Ic \&Lb Ta function library (one argument)
620.It Ic \&In Ta include file (one argument)
621.It Ic \&Fd Ta other preprocessor directive (>0 arguments)
622.It Ic \&Ft Ta function type (>0 arguments)
623.It Ic \&Fo , \&Fc Ta function block: Ar funcname
624.It Ic \&Fn Ta function name: Ar funcname Op Ar argument ...
625.It Ic \&Fa Ta function argument (>0 arguments)
626.It Ic \&Vt Ta variable type (>0 arguments)
627.It Ic \&Va Ta variable name (>0 arguments)
628.It Ic \&Dv Ta defined variable or preprocessor constant (>0 arguments)
629.It Ic \&Er Ta error constant (>0 arguments)
630.It Ic \&Ev Ta environmental variable (>0 arguments)
631.El
632.Ss Various semantic markup
633.Bl -column "Brq, Bro, Brc" description
634.It Ic \&An Ta author name (>0 arguments)
635.It Ic \&Lk Ta hyperlink: Ar uri Op Ar display_name
636.It Ic \&Mt Ta Do mailto Dc hyperlink: Ar localpart Ns @ Ns Ar domain
637.It Ic \&Cd Ta kernel configuration declaration (>0 arguments)
638.It Ic \&Ad Ta memory address (>0 arguments)
639.It Ic \&Ms Ta mathematical symbol (>0 arguments)
640.El
641.Ss Physical markup
642.Bl -column "Brq, Bro, Brc" description
643.It Ic \&Em Ta italic font or underline (emphasis) (>0 arguments)
644.It Ic \&Sy Ta boldface font (symbolic) (>0 arguments)
645.It Ic \&No Ta return to roman font (normal) (>0 arguments)
646.It Ic \&Bf , \&Ef Ta font block: Fl Ar type | Cm \&Em | \&Li | \&Sy
647.El
648.Ss Physical enclosures
649.Bl -column "Brq, Bro, Brc" description
650.It Ic \&Dq , \&Do , \&Dc Ta enclose in typographic double quotes: Dq text
651.It Ic \&Qq , \&Qo , \&Qc Ta enclose in typewriter double quotes: Qq text
652.It Ic \&Sq , \&So , \&Sc Ta enclose in single quotes: Sq text
653.It Ic \&Pq , \&Po , \&Pc Ta enclose in parentheses: Pq text
654.It Ic \&Bq , \&Bo , \&Bc Ta enclose in square brackets: Bq text
655.It Ic \&Brq , \&Bro , \&Brc Ta enclose in curly braces: Brq text
656.It Ic \&Aq , \&Ao , \&Ac Ta enclose in angle brackets: Aq text
657.It Ic \&Eo , \&Ec Ta generic enclosure
658.El
659.Ss Text production
660.Bl -column "Brq, Bro, Brc" description
661.It Ic \&Ex Fl std Ta standard command exit values: Op Ar utility ...
662.It Ic \&Rv Fl std Ta standard function return values: Op Ar function ...
663.It Ic \&St Ta reference to a standards document (one argument)
664.It Ic \&At Ta At
665.It Ic \&Bx Ta Bx
666.It Ic \&Bsx Ta Bsx
667.It Ic \&Nx Ta Nx
668.It Ic \&Fx Ta Fx
669.It Ic \&Ox Ta Ox
670.It Ic \&Dx Ta Dx
671.El
672.Sh MACRO REFERENCE
673This section is a canonical reference of all macros, arranged
674alphabetically.
675For the scoping of individual macros, see
676.Sx MACRO SYNTAX .
677.Bl -tag -width 3n
678.It Ic \&%A Ar first_name ... last_name
679Author name of an
680.Ic \&Rs
681block.
682Multiple authors should each be accorded their own
683.Ic \%%A
684line.
685Author names should be ordered with full or abbreviated forename(s)
686first, then full surname.
687.It Ic \&%B Ar title
688Book title of an
689.Ic \&Rs
690block.
691This macro may also be used in a non-bibliographic context when
692referring to book titles.
693.It Ic \&%C Ar location
694Publication city or location of an
695.Ic \&Rs
696block.
697.It Ic \&%D Oo Ar month day , Oc Ar year
698Publication date of an
699.Ic \&Rs
700block.
701Provide the full English name of the
702.Ar month
703and all four digits of the
704.Ar year .
705.It Ic \&%I Ar name
706Publisher or issuer name of an
707.Ic \&Rs
708block.
709.It Ic \&%J Ar name
710Journal name of an
711.Ic \&Rs
712block.
713.It Ic \&%N Ar number
714Issue number (usually for journals) of an
715.Ic \&Rs
716block.
717.It Ic \&%O Ar line
718Optional information of an
719.Ic \&Rs
720block.
721.It Ic \&%P Ar number
722Book or journal page number of an
723.Ic \&Rs
724block.
725Conventionally, the argument starts with
726.Ql p.\&
727for a single page or
728.Ql pp.\&
729for a range of pages, for example:
730.Pp
731.Dl .%P pp. 42\e(en47
732.It Ic \&%Q Ar name
733Institutional author (school, government, etc.) of an
734.Ic \&Rs
735block.
736Multiple institutional authors should each be accorded their own
737.Ic \&%Q
738line.
739.It Ic \&%R Ar name
740Technical report name of an
741.Ic \&Rs
742block.
743.It Ic \&%T Ar title
744Article title of an
745.Ic \&Rs
746block.
747This macro may also be used in a non-bibliographical context when
748referring to article titles.
749.It Ic \&%U Ar protocol Ns :// Ns Ar path
750URI of reference document.
751.It Ic \&%V Ar number
752Volume number of an
753.Ic \&Rs
754block.
755.It Ic \&Ac
756Close an
757.Ic \&Ao
758block.
759Does not have any tail arguments.
760.Tg Ad
761.It Ic \&Ad Ar address
762Memory address.
763Do not use this for postal addresses.
764.Pp
765Examples:
766.Dl \&.Ad [0,$]
767.Dl \&.Ad 0x00000000
768.Tg An
769.It Ic \&An Fl split | nosplit | Ar first_name ... last_name
770Author name.
771Can be used both for the authors of the program, function, or driver
772documented in the manual, or for the authors of the manual itself.
773Requires either the name of an author or one of the following arguments:
774.Pp
775.Bl -tag -width "-nosplitX" -offset indent -compact
776.It Fl split
777Start a new output line before each subsequent invocation of
778.Ic \&An .
779.It Fl nosplit
780The opposite of
781.Fl split .
782.El
783.Pp
784The default is
785.Fl nosplit .
786The effect of selecting either of the
787.Fl split
788modes ends at the beginning of the
789.Em AUTHORS
790section.
791In the
792.Em AUTHORS
793section, the default is
794.Fl nosplit
795for the first author listing and
796.Fl split
797for all other author listings.
798.Pp
799Examples:
800.Dl \&.An -nosplit
801.Dl \&.An Kristaps Dzonsons \&Aq \&Mt kristaps@bsd.lv
802.It Ic \&Ao Ar block
803Begin a block enclosed by angle brackets.
804Does not have any head arguments.
805This macro is almost never useful.
806See
807.Ic \&Aq
808for more details.
809.Tg Ap
810.It Ic \&Ap
811Inserts an apostrophe without any surrounding whitespace.
812This is generally used as a grammatical device when referring to the verb
813form of a function.
814.Pp
815Examples:
816.Dl \&.Fn execve \&Ap d
817.Tg Aq
818.It Ic \&Aq Ar line
819Enclose the rest of the input line in angle brackets.
820The only important use case is for email addresses.
821See
822.Ic \&Mt
823for an example.
824.Pp
825Occasionally, it is used for names of characters and keys, for example:
826.Bd -literal -offset indent
827Press the
828\&.Aq escape
829key to ...
830.Ed
831.Pp
832For URIs, use
833.Ic \&Lk
834instead, and
835.Ic \&In
836for
837.Dq #include
838directives.
839Never wrap
840.Ic \&Ar
841in
842.Ic \&Aq .
843.Pp
844Since
845.Ic \&Aq
846usually renders with non-ASCII characters in non-ASCII output modes,
847do not use it where the ASCII characters
848.Sq <
849and
850.Sq >
851are required as syntax elements.
852Instead, use these characters directly in such cases, combining them
853with the macros
854.Ic \&Pf ,
855.Ic \&Ns ,
856or
857.Ic \&Eo
858as needed.
859.Pp
860See also
861.Ic \&Ao .
862.Tg Ar
863.It Ic \&Ar Op Ar placeholder ...
864Command arguments.
865If an argument is not provided, the string
866.Dq file ...\&
867is used as a default.
868.Pp
869Examples:
870.Dl ".Fl o Ar file"
871.Dl ".Ar"
872.Dl ".Ar arg1 , arg2 ."
873.Pp
874The arguments to the
875.Ic \&Ar
876macro are names and placeholders for command arguments;
877for fixed strings to be passed verbatim as arguments, use
878.Ic \&Fl
879or
880.Ic \&Cm .
881.Tg At
882.It Ic \&At Op Ar version
883Formats an
884.At
885version.
886Accepts one optional argument:
887.Pp
888.Bl -tag -width "v[1-7] | 32vX" -offset indent -compact
889.It Cm v[1-7] | 32v
890A version of
891.At .
892.It Cm III
893.At III .
894.It Cm V | V.[1-4]
895A version of
896.At V .
897.El
898.Pp
899Note that these arguments do not begin with a hyphen.
900.Pp
901Examples:
902.Dl \&.At
903.Dl \&.At III
904.Dl \&.At V.1
905.Pp
906See also
907.Ic \&Bsx ,
908.Ic \&Bx ,
909.Ic \&Dx ,
910.Ic \&Fx ,
911.Ic \&Nx ,
912and
913.Ic \&Ox .
914.It Ic \&Bc
915Close a
916.Ic \&Bo
917block.
918Does not have any tail arguments.
919.Tg Bd
920.It Ic \&Bd Fl Ns Ar type Oo Fl offset Ar width Oc Op Fl compact
921Begin a display block.
922Display blocks are used to select a different indentation and
923justification than the one used by the surrounding text.
924They may contain both macro lines and text lines.
925By default, a display block is preceded by a vertical space.
926.Pp
927The
928.Ar type
929must be one of the following:
930.Bl -tag -width 13n -offset indent
931.It Fl centered
932Produce one output line from each input line, and center-justify each line.
933Using this display type is not recommended; many
934.Nm
935implementations render it poorly.
936.It Fl filled
937Change the positions of line breaks to fill each line, and left- and
938right-justify the resulting block.
939.It Fl literal
940Produce one output line from each input line,
941and do not justify the block at all.
942Preserve white space as it appears in the input.
943Always use a constant-width font.
944Use this for displaying source code.
945.It Fl ragged
946Change the positions of line breaks to fill each line, and left-justify
947the resulting block.
948.It Fl unfilled
949The same as
950.Fl literal ,
951but using the same font as for normal text, which is a variable width font
952if supported by the output device.
953.El
954.Pp
955The
956.Ar type
957must be provided first.
958Additional arguments may follow:
959.Bl -tag -width 13n -offset indent
960.It Fl offset Ar width
961Indent the display by the
962.Ar width ,
963which may be one of the following:
964.Bl -item
965.It
966One of the pre-defined strings
967.Cm indent ,
968the width of a standard indentation (six constant width characters);
969.Cm indent-two ,
970twice
971.Cm indent ;
972.Cm left ,
973which has no effect;
974.Cm right ,
975which justifies to the right margin; or
976.Cm center ,
977which aligns around an imagined center axis.
978.It
979A macro invocation, which selects a predefined width
980associated with that macro.
981The most popular is the imaginary macro
982.Ar \&Ds ,
983which resolves to
984.Sy 6n .
985.It
986A scaling width as described in
987.Xr mandoc_roff 7 .
988.It
989An arbitrary string, which indents by the length of this string.
990.El
991.Pp
992When the argument is missing,
993.Fl offset
994is ignored.
995.It Fl compact
996Do not assert vertical space before the display.
997.El
998.Pp
999Examples:
1000.Bd -literal -offset indent
1001\&.Bd \-literal \-offset indent \-compact
1002   Hello       world.
1003\&.Ed
1004.Ed
1005.Pp
1006See also
1007.Ic \&D1
1008and
1009.Ic \&Dl .
1010.Tg Bf
1011.It Ic \&Bf Fl emphasis | literal | symbolic | Cm \&Em | \&Li | \&Sy
1012Change the font mode for a scoped block of text.
1013The
1014.Fl emphasis
1015and
1016.Cm \&Em
1017argument are equivalent, as are
1018.Fl symbolic
1019and
1020.Cm \&Sy ,
1021and
1022.Fl literal
1023and
1024.Cm \&Li .
1025Without an argument, this macro does nothing.
1026The font mode continues until broken by a new font mode in a nested
1027scope or
1028.Ic \&Ef
1029is encountered.
1030.Pp
1031See also
1032.Ic \&Li ,
1033.Ic \&Ef ,
1034.Ic \&Em ,
1035and
1036.Ic \&Sy .
1037.Tg Bk
1038.It Ic \&Bk Fl words
1039For each macro, keep its output together on the same output line,
1040until the end of the macro or the end of the input line is reached,
1041whichever comes first.
1042Line breaks in text lines are unaffected.
1043.Pp
1044The
1045.Fl words
1046argument is required; additional arguments are ignored.
1047.Pp
1048The following example will not break within each
1049.Ic \&Op
1050macro line:
1051.Bd -literal -offset indent
1052\&.Bk \-words
1053\&.Op Fl f Ar flags
1054\&.Op Fl o Ar output
1055\&.Ek
1056.Ed
1057.Pp
1058Be careful in using over-long lines within a keep block!
1059Doing so will clobber the right margin.
1060.Tg Bl
1061.It Xo
1062.Ic \&Bl
1063.Fl Ns Ar type
1064.Op Fl width Ar val
1065.Op Fl offset Ar val
1066.Op Fl compact
1067.Op Ar col ...
1068.Xc
1069Begin a list.
1070Lists consist of items specified using the
1071.Ic \&It
1072macro, containing a head or a body or both.
1073.Pp
1074The list
1075.Ar type
1076is mandatory and must be specified first.
1077The
1078.Fl width
1079and
1080.Fl offset
1081arguments accept macro names as described for
1082.Ic \&Bd
1083.Fl offset ,
1084scaling widths as described in
1085.Xr mandoc_roff 7 ,
1086or use the length of the given string.
1087The
1088.Fl offset
1089is a global indentation for the whole list, affecting both item heads
1090and bodies.
1091For those list types supporting it, the
1092.Fl width
1093argument requests an additional indentation of item bodies,
1094to be added to the
1095.Fl offset .
1096Unless the
1097.Fl compact
1098argument is specified, list entries are separated by vertical space.
1099.Pp
1100A list must specify one of the following list types:
1101.Bl -tag -width 12n -offset indent
1102.It Fl bullet
1103No item heads can be specified, but a bullet will be printed at the head
1104of each item.
1105Item bodies start on the same output line as the bullet
1106and are indented according to the
1107.Fl width
1108argument.
1109.It Fl column
1110A columnated list.
1111The
1112.Fl width
1113argument has no effect; instead, the string length of each argument
1114specifies the width of one column.
1115If the first line of the body of a
1116.Fl column
1117list is not an
1118.Ic \&It
1119macro line,
1120.Ic \&It
1121contexts spanning one input line each are implied until an
1122.Ic \&It
1123macro line is encountered, at which point items start being interpreted as
1124described in the
1125.Ic \&It
1126documentation.
1127.It Fl dash
1128Like
1129.Fl bullet ,
1130except that dashes are used in place of bullets.
1131.It Fl diag
1132Like
1133.Fl inset ,
1134except that item heads are not parsed for macro invocations.
1135Most often used in the
1136.Em DIAGNOSTICS
1137section with error constants in the item heads.
1138.It Fl enum
1139A numbered list.
1140No item heads can be specified.
1141Formatted like
1142.Fl bullet ,
1143except that cardinal numbers are used in place of bullets,
1144starting at 1.
1145.It Fl hang
1146Like
1147.Fl tag ,
1148except that the first lines of item bodies are not indented, but follow
1149the item heads like in
1150.Fl inset
1151lists.
1152.It Fl hyphen
1153Synonym for
1154.Fl dash .
1155.It Fl inset
1156Item bodies follow items heads on the same line, using normal inter-word
1157spacing.
1158Bodies are not indented, and the
1159.Fl width
1160argument is ignored.
1161.It Fl item
1162No item heads can be specified, and none are printed.
1163Bodies are not indented, and the
1164.Fl width
1165argument is ignored.
1166.It Fl ohang
1167Item bodies start on the line following item heads and are not indented.
1168The
1169.Fl width
1170argument is ignored.
1171.It Fl tag
1172Item bodies are indented according to the
1173.Fl width
1174argument.
1175When an item head fits inside the indentation, the item body follows
1176this head on the same output line.
1177Otherwise, the body starts on the output line following the head.
1178.El
1179.Pp
1180Lists may be nested within lists and displays.
1181Nesting of
1182.Fl column
1183and
1184.Fl enum
1185lists may not be portable.
1186.Pp
1187See also
1188.Ic \&El
1189and
1190.Ic \&It .
1191.It Ic \&Bo Ar block
1192Begin a block enclosed by square brackets.
1193Does not have any head arguments.
1194.Pp
1195Examples:
1196.Bd -literal -offset indent -compact
1197\&.Bo 1 ,
1198\&.Dv BUFSIZ \&Bc
1199.Ed
1200.Pp
1201See also
1202.Ic \&Bq .
1203.Tg Bq
1204.It Ic \&Bq Ar line
1205Encloses its arguments in square brackets.
1206.Pp
1207Examples:
1208.Dl \&.Bq 1 , \&Dv BUFSIZ
1209.Pp
1210.Em Remarks :
1211this macro is sometimes abused to emulate optional arguments for
1212commands; the correct macros to use for this purpose are
1213.Ic \&Op ,
1214.Ic \&Oo ,
1215and
1216.Ic \&Oc .
1217.Pp
1218See also
1219.Ic \&Bo .
1220.It Ic \&Brc
1221Close a
1222.Ic \&Bro
1223block.
1224Does not have any tail arguments.
1225.It Ic \&Bro Ar block
1226Begin a block enclosed by curly braces.
1227Does not have any head arguments.
1228.Pp
1229Examples:
1230.Bd -literal -offset indent -compact
1231\&.Bro 1 , ... ,
1232\&.Va n \&Brc
1233.Ed
1234.Pp
1235See also
1236.Ic \&Brq .
1237.Tg Brq
1238.It Ic \&Brq Ar line
1239Encloses its arguments in curly braces.
1240.Pp
1241Examples:
1242.Dl \&.Brq 1 , ... , \&Va n
1243.Pp
1244See also
1245.Ic \&Bro .
1246.Tg Bsx
1247.It Ic \&Bsx Op Ar version
1248Format the
1249.Bsx
1250version provided as an argument, or a default value if
1251no argument is provided.
1252.Pp
1253Examples:
1254.Dl \&.Bsx 1.0
1255.Dl \&.Bsx
1256.Pp
1257See also
1258.Ic \&At ,
1259.Ic \&Bx ,
1260.Ic \&Dx ,
1261.Ic \&Fx ,
1262.Ic \&Nx ,
1263and
1264.Ic \&Ox .
1265.It Ic \&Bt
1266Supported only for compatibility, do not use this in new manuals.
1267Prints
1268.Dq is currently in beta test.
1269.Tg Bx
1270.It Ic \&Bx Op Ar version Op Ar variant
1271Format the
1272.Bx
1273version provided as an argument, or a default value if no
1274argument is provided.
1275.Pp
1276Examples:
1277.Dl \&.Bx 4.3 Tahoe
1278.Dl \&.Bx 4.4
1279.Dl \&.Bx
1280.Pp
1281See also
1282.Ic \&At ,
1283.Ic \&Bsx ,
1284.Ic \&Dx ,
1285.Ic \&Fx ,
1286.Ic \&Nx ,
1287and
1288.Ic \&Ox .
1289.Tg Cd
1290.It Ic \&Cd Ar line
1291Kernel configuration declaration.
1292It is found in pages for
1293.Bx
1294and not used here.
1295.Pp
1296Examples:
1297.Dl \&.Cd device le0 at scode?
1298.Pp
1299.Em Remarks :
1300this macro is commonly abused by using quoted literals to retain
1301whitespace and align consecutive
1302.Ic \&Cd
1303declarations.
1304This practise is discouraged.
1305.Tg Cm
1306.It Ic \&Cm Ar keyword ...
1307Command modifiers.
1308Typically used for fixed strings passed as arguments to interactive
1309commands, to commands in interpreted scripts, or to configuration
1310file directives, unless
1311.Ic \&Fl
1312is more appropriate.
1313Also useful when specifying configuration options or keys.
1314.Pp
1315Examples:
1316.Dl ".Nm mt Fl f Ar device Cm rewind"
1317.Dl ".Nm ps Fl o Cm pid , Ns Cm command"
1318.Dl ".Nm dd Cm if= Ns Ar file1 Cm of= Ns Ar file2"
1319.Dl ".Ic set Fl o Cm vi"
1320.Dl ".Ic lookup Cm file bind"
1321.Dl ".Ic permit Ar identity Op Cm as Ar target"
1322.Tg D1
1323.It Ic \&D1 Ar line
1324One-line indented display.
1325This is formatted by the default rules and is useful for simple indented
1326statements.
1327It is followed by a newline.
1328.Pp
1329Examples:
1330.Dl \&.D1 \&Fl abcdefgh
1331.Pp
1332See also
1333.Ic \&Bd
1334and
1335.Ic \&Dl .
1336.It Ic \&Db
1337This macro is obsolete.
1338No replacement is needed.
1339It is ignored by
1340.Xr mandoc 1
1341and groff including its arguments.
1342It was formerly used to toggle a debugging mode.
1343.It Ic \&Dc
1344Close a
1345.Ic \&Do
1346block.
1347Does not have any tail arguments.
1348.Tg Dd
1349.It Ic \&Dd Cm $\&Mdocdate$ | Ar month day , year
1350Document date for display in the page footer,
1351by convention the date of the last change.
1352This is the mandatory first macro of any
1353.Nm
1354manual.
1355.Pp
1356The
1357.Ar month
1358is the full English month name, the
1359.Ar day
1360is an integer number, and the
1361.Ar year
1362is the full four-digit year.
1363.Pp
1364Other arguments are not portable; the
1365.Xr mandoc 1
1366utility handles them as follows:
1367.Bl -dash -offset 3n -compact
1368.It
1369To have the date automatically filled in by the
1370.Ox
1371version of
1372.Xr cvs 1 ,
1373the special string
1374.Dq $\&Mdocdate$
1375can be given as an argument.
1376.It
1377The traditional, purely numeric
1378.Xr man 7
1379format
1380.Ar year Ns \(en Ns Ar month Ns \(en Ns Ar day
1381is accepted, too.
1382.It
1383If a date string cannot be parsed, it is used verbatim.
1384.It
1385If no date string is given, the current date is used.
1386.El
1387.Pp
1388Examples:
1389.Dl \&.Dd $\&Mdocdate$
1390.Dl \&.Dd $\&Mdocdate: July 2 2018$
1391.Dl \&.Dd July 2, 2018
1392.Pp
1393See also
1394.Ic \&Dt
1395and
1396.Ic \&Os .
1397.Tg Dl
1398.It Ic \&Dl Ar line
1399One-line indented display.
1400This is formatted as literal text and is useful for commands and
1401invocations.
1402It is followed by a newline.
1403.Pp
1404Examples:
1405.Dl \&.Dl % mandoc mdoc.5 \e(ba less
1406.Pp
1407See also
1408.Ic \&Ql ,
1409.Ic \&Bd Fl literal ,
1410and
1411.Ic \&D1 .
1412.It Ic \&Do Ar block
1413Begin a block enclosed by double quotes.
1414Does not have any head arguments.
1415.Pp
1416Examples:
1417.Bd -literal -offset indent -compact
1418\&.Do
1419April is the cruellest month
1420\&.Dc
1421\e(em T.S. Eliot
1422.Ed
1423.Pp
1424See also
1425.Ic \&Dq .
1426.Tg Dq
1427.It Ic \&Dq Ar line
1428Encloses its arguments in
1429.Dq typographic
1430double-quotes.
1431.Pp
1432Examples:
1433.Bd -literal -offset indent -compact
1434\&.Dq April is the cruellest month
1435\e(em T.S. Eliot
1436.Ed
1437.Pp
1438See also
1439.Ic \&Qq ,
1440.Ic \&Sq ,
1441and
1442.Ic \&Do .
1443.Tg Dt
1444.It Ic \&Dt Ar TITLE section Op Ar arch
1445Document title for display in the page header.
1446This is the mandatory second macro of any
1447.Nm
1448file.
1449.Pp
1450Its arguments are as follows:
1451.Bl -tag -width section -offset 2n
1452.It Ar TITLE
1453The document's title (name), defaulting to
1454.Dq UNTITLED
1455if unspecified.
1456To achieve a uniform appearance of page header lines,
1457it should by convention be all caps.
1458.It Ar SECTION
1459The manual section.
1460It should correspond to the manual's filename suffix and defaults to
1461the empty string if unspecified.
1462This field is optional.
1463To achieve a uniform appearance of page header lines,
1464it should by convention be all caps.
1465.It Ar arch
1466This specifies the machine architecture a manual page applies to,
1467where relevant.
1468.El
1469.It Ic \&Dv
1470Defined variables such as preprocessor constants, constant symbols,
1471enumeration values, and so on.
1472.Pp
1473Examples:
1474.Dl \&.Dv NULL
1475.Dl \&.Dv BUFSIZ
1476.Dl \&.Dv STDOUT_FILENO
1477.Pp
1478See also
1479.Ic \&Er
1480and
1481.Ic \&Ev
1482for special-purpose constants,
1483.Ic \&Va
1484for variable symbols, and
1485.Ic \&Fd
1486for listing preprocessor variable definitions in the
1487.Em SYNOPSIS .
1488.Tg Dx
1489.It Ic \&Dx Op Ar version
1490Format the
1491.Dx
1492version provided as an argument, or a default
1493value if no argument is provided.
1494.Pp
1495Examples:
1496.Dl \&.Dx 2.4.1
1497.Dl \&.Dx
1498.Pp
1499See also
1500.Ic \&At ,
1501.Ic \&Bsx ,
1502.Ic \&Bx ,
1503.Ic \&Fx ,
1504.Ic \&Nx ,
1505and
1506.Ic \&Ox .
1507.It Ic \&Ec Op Ar closing_delimiter
1508Close a scope started by
1509.Ic \&Eo .
1510.Pp
1511The
1512.Ar closing_delimiter
1513argument is used as the enclosure tail, for example, specifying \e(rq
1514will emulate
1515.Ic \&Dc .
1516.It Ic \&Ed
1517End a display context started by
1518.Ic \&Bd .
1519.It Ic \&Ef
1520End a font mode context started by
1521.Ic \&Bf .
1522.It Ic \&Ek
1523End a keep context started by
1524.Ic \&Bk .
1525.It Ic \&El
1526End a list context started by
1527.Ic \&Bl .
1528See also
1529.Ic \&It .
1530.Tg Em
1531.It Ic \&Em Ar word ...
1532Request an italic font.
1533If the output device does not provide that, underline.
1534.Pp
1535This is most often used for stress emphasis (not to be confused with
1536importance, see
1537.Ic \&Sy ) .
1538In the rare cases where none of the semantic markup macros fit,
1539it can also be used for technical terms and placeholders, except
1540that for syntax elements,
1541.Ic \&Sy
1542and
1543.Ic \&Ar
1544are preferred, respectively.
1545.Pp
1546Examples:
1547.Bd -literal -compact -offset indent
1548Selected lines are those
1549\&.Em not
1550matching any of the specified patterns.
1551Some of the functions use a
1552\&.Em hold space
1553to save the pattern space for subsequent retrieval.
1554.Ed
1555.Pp
1556See also
1557.Ic \&No ,
1558.Ic \&Ql ,
1559and
1560.Ic \&Sy .
1561.It Ic \&En Ar word ...
1562This macro is obsolete.
1563Use
1564.Ic \&Eo
1565or any of the other enclosure macros.
1566.Pp
1567It encloses its argument in the delimiters specified by the last
1568.Ic \&Es
1569macro.
1570.Tg Eo
1571.It Ic \&Eo Op Ar opening_delimiter
1572An arbitrary enclosure.
1573The
1574.Ar opening_delimiter
1575argument is used as the enclosure head, for example, specifying \e(lq
1576will emulate
1577.Ic \&Do .
1578.Tg Er
1579.It Ic \&Er Ar identifier ...
1580Error constants for definitions of the
1581.Va errno
1582libc global variable.
1583This is most often used in section 2 and 3 manual pages.
1584.Pp
1585Examples:
1586.Dl \&.Er EPERM
1587.Dl \&.Er ENOENT
1588.Pp
1589See also
1590.Ic \&Dv
1591for general constants.
1592.It Ic \&Es Ar opening_delimiter closing_delimiter
1593This macro is obsolete.
1594Use
1595.Ic \&Eo
1596or any of the other enclosure macros.
1597.Pp
1598It takes two arguments, defining the delimiters to be used by subsequent
1599.Ic \&En
1600macros.
1601.Tg Ev
1602.It Ic \&Ev Ar identifier ...
1603Environmental variables such as those specified in
1604.Xr environ 7 .
1605.Pp
1606Examples:
1607.Dl \&.Ev DISPLAY
1608.Dl \&.Ev PATH
1609.Pp
1610See also
1611.Ic \&Dv
1612for general constants.
1613.Tg Ex
1614.It Ic \&Ex Fl std Op Ar utility ...
1615Insert a standard sentence regarding command exit values of 0 on success
1616and >0 on failure.
1617This is most often used in section 1 and 8 manual pages.
1618.Pp
1619If
1620.Ar utility
1621is not specified, the document's name set by
1622.Ic \&Nm
1623is used.
1624Multiple
1625.Ar utility
1626arguments are treated as separate utilities.
1627.Pp
1628See also
1629.Ic \&Rv .
1630.Tg Fa
1631.It Ic \&Fa Ar argument ...
1632Function argument or parameter.
1633Each argument may be a name and a type (recommended for the
1634.Em SYNOPSIS
1635section), a name alone (for function invocations),
1636or a type alone (for function prototypes).
1637If both a type and a name are given or if the type consists of multiple
1638words, all words belonging to the same function argument have to be
1639given in a single argument to the
1640.Ic \&Fa
1641macro.
1642.Pp
1643This macro is also used to specify the field name of a structure.
1644.Pp
1645Most often, the
1646.Ic \&Fa
1647macro is used in the
1648.Em SYNOPSIS
1649within
1650.Ic \&Fo
1651blocks when documenting multi-line function prototypes.
1652If invoked with multiple arguments, the arguments are separated by a
1653comma.
1654Furthermore, if the following macro is another
1655.Ic \&Fa ,
1656the last argument will also have a trailing comma.
1657.Pp
1658Examples:
1659.Dl \&.Fa \(dqconst char *p\(dq
1660.Dl \&.Fa \(dqint a\(dq \(dqint b\(dq \(dqint c\(dq
1661.Dl \&.Fa \(dqchar *\(dq size_t
1662.Pp
1663See also
1664.Ic \&Fo .
1665.It Ic \&Fc
1666End a function context started by
1667.Ic \&Fo .
1668.Tg Fd
1669.It Ic \&Fd Pf # Ar directive Op Ar argument ...
1670Preprocessor directive, in particular for listing it in the
1671.Em SYNOPSIS .
1672Historically, it was also used to document include files.
1673The latter usage has been deprecated in favour of
1674.Ic \&In .
1675.Pp
1676Examples:
1677.Dl \&.Fd #define sa_handler __sigaction_u.__sa_handler
1678.Dl \&.Fd #define SIO_MAXNFDS
1679.Dl \&.Fd #ifdef FS_DEBUG
1680.Dl \&.Ft void
1681.Dl \&.Fn dbg_open \(dqconst char *\(dq
1682.Dl \&.Fd #endif
1683.Pp
1684See also
1685.Sx MANUAL STRUCTURE ,
1686.Ic \&In ,
1687and
1688.Ic \&Dv .
1689.Tg Fl
1690.It Ic \&Fl Op Ar word ...
1691Command-line flag or option.
1692Used when listing arguments to command-line utilities.
1693For each argument, prints an ASCII hyphen-minus character
1694.Sq \- ,
1695immediately followed by the argument.
1696If no arguments are provided, a hyphen-minus is printed followed by a space.
1697If the argument is a macro, a hyphen-minus is prefixed
1698to the subsequent macro output.
1699.Pp
1700Examples:
1701.Dl ".Nm du Op Fl H | L | P"
1702.Dl ".Nm ls Op Fl 1AaCcdFfgHhikLlmnopqRrSsTtux"
1703.Dl ".Nm route Cm add Fl inet Ar destination gateway"
1704.Dl ".Nm locate.updatedb Op Fl \e-fcodes Ns = Ns Ar dbfile"
1705.Dl ".Nm aucat Fl o Fl"
1706.Dl ".Nm kill Fl Ar signal_number"
1707.Pp
1708For GNU-sytle long options, escaping the additional hyphen-minus is not
1709strictly required, but may be safer with future versions of GNU troff; see
1710.Xr mandoc_char 7
1711for details.
1712.Pp
1713See also
1714.Ic \&Cm .
1715.Tg Fn
1716.It Ic \&Fn Ar funcname Op Ar argument ...
1717A function name.
1718.Pp
1719Function arguments are surrounded in parenthesis and
1720are delimited by commas.
1721If no arguments are specified, blank parenthesis are output.
1722In the
1723.Em SYNOPSIS
1724section, this macro starts a new output line,
1725and a blank line is automatically inserted between function definitions.
1726.Pp
1727Examples:
1728.Dl \&.Fn \(dqint funcname\(dq \(dqint arg0\(dq \(dqint arg1\(dq
1729.Dl \&.Fn funcname \(dqint arg0\(dq
1730.Dl \&.Fn funcname arg0
1731.Bd -literal -offset indent
1732\&.Ft functype
1733\&.Fn funcname
1734.Ed
1735.Pp
1736When referring to a function documented in another manual page, use
1737.Ic \&Xr
1738instead.
1739See also
1740.Sx MANUAL STRUCTURE ,
1741.Ic \&Fo ,
1742and
1743.Ic \&Ft .
1744.Tg Fo
1745.It Ic \&Fo Ar funcname
1746Begin a function block.
1747This is a multi-line version of
1748.Ic \&Fn .
1749.Pp
1750Invocations usually occur in the following context:
1751.Bd -ragged -offset indent
1752.Pf \. Ic \&Ft Ar functype
1753.br
1754.Pf \. Ic \&Fo Ar funcname
1755.br
1756.Pf \. Ic \&Fa Qq Ar argtype Ar argname
1757.br
1758\&.\.\.
1759.br
1760.Pf \. Ic \&Fc
1761.Ed
1762.Pp
1763A
1764.Ic \&Fo
1765scope is closed by
1766.Ic \&Fc .
1767.Pp
1768See also
1769.Sx MANUAL STRUCTURE ,
1770.Ic \&Fa ,
1771.Ic \&Fc ,
1772and
1773.Ic \&Ft .
1774.It Ic \&Fr Ar number
1775This macro is obsolete.
1776No replacement markup is needed.
1777.Pp
1778It was used to show numerical function return values in an italic font.
1779.Tg Ft
1780.It Ic \&Ft Ar functype
1781A function type.
1782.Pp
1783In the
1784.Em SYNOPSIS
1785section, a new output line is started after this macro.
1786.Pp
1787Examples:
1788.Dl \&.Ft int
1789.Bd -literal -offset indent -compact
1790\&.Ft functype
1791\&.Fn funcname
1792.Ed
1793.Pp
1794See also
1795.Sx MANUAL STRUCTURE ,
1796.Ic \&Fn ,
1797and
1798.Ic \&Fo .
1799.Tg Fx
1800.It Ic \&Fx Op Ar version
1801Format the
1802.Fx
1803version provided as an argument, or a default value
1804if no argument is provided.
1805.Pp
1806Examples:
1807.Dl \&.Fx 7.1
1808.Dl \&.Fx
1809.Pp
1810See also
1811.Ic \&At ,
1812.Ic \&Bsx ,
1813.Ic \&Bx ,
1814.Ic \&Dx ,
1815.Ic \&Nx ,
1816and
1817.Ic \&Ox .
1818.It Ic \&Hf Ar filename
1819This macro is not implemented in
1820.Xr mandoc 1 .
1821It was used to include the contents of a (header) file literally.
1822.Tg Ic
1823.It Ic \&Ic Ar keyword ...
1824Internal or interactive command, or configuration instruction
1825in a configuration file.
1826See also
1827.Ic \&Cm .
1828.Pp
1829Examples:
1830.Dl \&.Ic :wq
1831.Dl \&.Ic hash
1832.Dl \&.Ic alias
1833.Pp
1834Note that using
1835.Ic \&Ql ,
1836.Ic \&Dl ,
1837or
1838.Ic \&Bd Fl literal
1839is preferred for displaying code samples; the
1840.Ic \&Ic
1841macro is used when referring to an individual command name.
1842.Tg In
1843.It Ic \&In Ar filename
1844The name of an include file.
1845This macro is most often used in section 2, 3, and 9 manual pages.
1846.Pp
1847When invoked as the first macro on an input line in the
1848.Em SYNOPSIS
1849section, the argument is displayed in angle brackets
1850and preceded by
1851.Qq #include ,
1852and a blank line is inserted in front if there is a preceding
1853function declaration.
1854In other sections, it only encloses its argument in angle brackets
1855and causes no line break.
1856.Pp
1857Examples:
1858.Dl \&.In sys/types.h
1859.Pp
1860See also
1861.Sx MANUAL STRUCTURE .
1862.Tg It
1863.It Ic \&It Op Ar head
1864A list item.
1865The syntax of this macro depends on the list type.
1866.Pp
1867Lists
1868of type
1869.Fl hang ,
1870.Fl ohang ,
1871.Fl inset ,
1872and
1873.Fl diag
1874have the following syntax:
1875.Pp
1876.D1 Pf \. Ic \&It Ar args
1877.Pp
1878Lists of type
1879.Fl bullet ,
1880.Fl dash ,
1881.Fl enum ,
1882.Fl hyphen
1883and
1884.Fl item
1885have the following syntax:
1886.Pp
1887.D1 Pf \. Ic \&It
1888.Pp
1889with subsequent lines interpreted within the scope of the
1890.Ic \&It
1891until either a closing
1892.Ic \&El
1893or another
1894.Ic \&It .
1895.Pp
1896The
1897.Fl tag
1898list has the following syntax:
1899.Pp
1900.D1 Pf \. Ic \&It Op Cm args
1901.Pp
1902Subsequent lines are interpreted as with
1903.Fl bullet
1904and family.
1905The line arguments correspond to the list's left-hand side; body
1906arguments correspond to the list's contents.
1907.Pp
1908The
1909.Fl column
1910list is the most complicated.
1911Its syntax is as follows:
1912.Pp
1913.D1 Pf \. Ic \&It Ar cell Op Ic \&Ta Ar cell ...
1914.D1 Pf \. Ic \&It Ar cell Op <TAB> Ar cell ...
1915.Pp
1916The arguments consist of one or more lines of text and macros
1917representing a complete table line.
1918Cells within the line are delimited by the special
1919.Ic \&Ta
1920block macro or by literal tab characters.
1921.Pp
1922Using literal tabs is strongly discouraged because they are very
1923hard to use correctly and
1924.Nm
1925code using them is very hard to read.
1926In particular, a blank character is syntactically significant
1927before and after the literal tab character.
1928If a word precedes or follows the tab without an intervening blank,
1929that word is never interpreted as a macro call, but always output
1930literally.
1931.Pp
1932The tab cell delimiter may only be used within the
1933.Ic \&It
1934line itself; on following lines, only the
1935.Ic \&Ta
1936macro can be used to delimit cells, and portability requires that
1937.Ic \&Ta
1938is called by other macros: some parsers do not recognize it when
1939it appears as the first macro on a line.
1940.Pp
1941Note that quoted strings may span tab-delimited cells on an
1942.Ic \&It
1943line.
1944For example,
1945.Pp
1946.Dl .It \(dqcol1 ,\& <TAB> col2 ,\(dq \&;
1947.Pp
1948will preserve the whitespace before both commas,
1949but not the whitespace before the semicolon.
1950.Pp
1951See also
1952.Ic \&Bl .
1953.Tg Lb
1954.It Ic \&Lb Cm lib Ns Ar name
1955Specify a library.
1956.Pp
1957The
1958.Ar name
1959parameter may be a system library, such as
1960.Cm z
1961or
1962.Cm pam ,
1963in which case a small library description is printed next to the linker
1964invocation; or a custom library, in which case the library name is
1965printed in quotes.
1966This is most commonly used in the
1967.Em SYNOPSIS
1968section as described in
1969.Sx MANUAL STRUCTURE .
1970.Pp
1971Examples:
1972.Dl \&.Lb libz
1973.Dl \&.Lb libmandoc
1974.Tg Li
1975.It Ic \&Li Ar word ...
1976Request a typewriter (literal) font.
1977Deprecated because on terminal output devices, this is usually
1978indistinguishable from normal text.
1979For literal displays, use
1980.Ic \&Ql Pq in-line ,
1981.Ic \&Dl Pq single line ,
1982or
1983.Ic \&Bd Fl literal Pq multi-line
1984instead.
1985.Tg Lk
1986.It Ic \&Lk Ar uri Op Ar display_name
1987Format a hyperlink.
1988.Pp
1989Examples:
1990.Dl \&.Lk https://bsd.lv \(dqThe BSD.lv Project\(dq
1991.Dl \&.Lk https://bsd.lv
1992.Pp
1993See also
1994.Ic \&Mt .
1995.It Ic \&Lp
1996Deprecated synonym for
1997.Ic \&Pp .
1998.Tg Ms
1999.It Ic \&Ms Ar name
2000Display a mathematical symbol.
2001.Pp
2002Examples:
2003.Dl \&.Ms sigma
2004.Dl \&.Ms aleph
2005.Tg Mt
2006.It Ic \&Mt Ar localpart Ns @ Ns Ar domain
2007Format a
2008.Dq mailto:
2009hyperlink.
2010.Pp
2011Examples:
2012.Dl \&.Mt discuss@manpages.bsd.lv
2013.Dl \&.An Kristaps Dzonsons \&Aq \&Mt kristaps@bsd.lv
2014.Tg Nd
2015.It Ic \&Nd Ar line
2016A one line description of the manual's content.
2017This is the mandatory last macro of the
2018.Em NAME
2019section and not appropriate for other sections.
2020.Pp
2021Examples:
2022.Dl Pf . Ic \&Nd mdoc language reference
2023.Dl Pf . Ic \&Nd format and display UNIX manuals
2024.Pp
2025The
2026.Ic \&Nd
2027macro technically accepts child macros and terminates with a subsequent
2028.Ic \&Sh
2029invocation.
2030Do not assume this behaviour: some
2031.Xr whatis 1
2032database generators are not smart enough to parse more than the line
2033arguments and will display macros verbatim.
2034.Pp
2035See also
2036.Ic \&Nm .
2037.Tg Nm
2038.It Ic \&Nm Op Ar name
2039The name of the manual page, or \(em in particular in section 1
2040pages \(em of an additional command or feature documented in
2041the manual page.
2042When first invoked, the
2043.Ic \&Nm
2044macro expects a single argument, the name of the manual page.
2045Usually, the first invocation happens in the
2046.Em NAME
2047section of the page.
2048The specified name will be remembered and used whenever the macro is
2049called again without arguments later in the page.
2050The
2051.Ic \&Nm
2052macro uses
2053.Sx Block full-implicit
2054semantics when invoked as the first macro on an input line in the
2055.Em SYNOPSIS
2056section; otherwise, it uses ordinary
2057.Sx In-line
2058semantics.
2059.Pp
2060Examples:
2061.Bd -literal -offset indent
2062\&.Sh SYNOPSIS
2063\&.Nm cat
2064\&.Op Fl benstuv
2065\&.Op Ar
2066.Ed
2067.Pp
2068In the
2069.Em SYNOPSIS
2070of section 2, 3 and 9 manual pages, use the
2071.Ic \&Fn
2072macro rather than
2073.Ic \&Nm
2074to mark up the name of the manual page.
2075.Tg No
2076.It Ic \&No Ar word ...
2077Normal text.
2078Closes the scope of any preceding in-line macro.
2079When used after physical formatting macros like
2080.Ic \&Em
2081or
2082.Ic \&Sy ,
2083switches back to the standard font face and weight.
2084Can also be used to embed plain text strings in macro lines
2085using semantic annotation macros.
2086.Pp
2087Examples:
2088.Dl ".Em italic , Sy bold , No and roman"
2089.Bd -literal -offset indent
2090\&.Sm off
2091\&.Cm :C No / Ar pattern No / Ar replacement No /
2092\&.Sm on
2093.Ed
2094.Pp
2095See also
2096.Ic \&Em ,
2097.Ic \&Ql ,
2098and
2099.Ic \&Sy .
2100.Tg Ns
2101.It Ic \&Ns
2102Suppress a space between the output of the preceding macro
2103and the following text or macro.
2104Following invocation, input is interpreted as normal text
2105just like after an
2106.Ic \&No
2107macro.
2108.Pp
2109This has no effect when invoked at the start of a macro line.
2110.Pp
2111Examples:
2112.Dl ".Ar name Ns = Ns Ar value"
2113.Dl ".Cm :M Ns Ar pattern"
2114.Dl ".Fl o Ns Ar output"
2115.Pp
2116See also
2117.Ic \&No
2118and
2119.Ic \&Sm .
2120.Tg Nx
2121.It Ic \&Nx Op Ar version
2122Format the
2123.Nx
2124version provided as an argument, or a default value if
2125no argument is provided.
2126.Pp
2127Examples:
2128.Dl \&.Nx 5.01
2129.Dl \&.Nx
2130.Pp
2131See also
2132.Ic \&At ,
2133.Ic \&Bsx ,
2134.Ic \&Bx ,
2135.Ic \&Dx ,
2136.Ic \&Fx ,
2137and
2138.Ic \&Ox .
2139.It Ic \&Oc
2140Close multi-line
2141.Ic \&Oo
2142context.
2143.It Ic \&Oo Ar block
2144Multi-line version of
2145.Ic \&Op .
2146.Pp
2147Examples:
2148.Bd -literal -offset indent -compact
2149\&.Oo
2150\&.Op Fl flag Ns Ar value
2151\&.Oc
2152.Ed
2153.Tg Op
2154.It Ic \&Op Ar line
2155Optional part of a command line.
2156Prints the argument(s) in brackets.
2157This is most often used in the
2158.Em SYNOPSIS
2159section of section 1 and 8 manual pages.
2160.Pp
2161Examples:
2162.Dl \&.Op \&Fl a \&Ar b
2163.Dl \&.Op \&Ar a | b
2164.Pp
2165See also
2166.Ic \&Oo .
2167.Tg Os
2168.It Ic \&Os Op Ar system Op Ar version
2169Operating system version for display in the page footer.
2170This is the mandatory third macro of
2171any
2172.Nm
2173file.
2174.Pp
2175The optional
2176.Ar system
2177parameter specifies the relevant operating system or environment.
2178It is suggested to leave it unspecified, in which case
2179.Xr mandoc 1
2180uses its
2181.Fl Ios
2182argument or, if that isn't specified either,
2183.Fa sysname
2184and
2185.Fa release
2186as returned by
2187.Xr uname 2 .
2188.Pp
2189Examples:
2190.Dl \&.Os
2191.Dl \&.Os KTH/CSC/TCS
2192.Dl \&.Os BSD 4.3
2193.Pp
2194See also
2195.Ic \&Dd
2196and
2197.Ic \&Dt .
2198.It Ic \&Ot Ar functype
2199This macro is obsolete.
2200Use
2201.Ic \&Ft
2202instead; with
2203.Xr mandoc 1 ,
2204both have the same effect.
2205.Pp
2206Historical
2207.Nm
2208packages described it as
2209.Dq "old function type (FORTRAN)" .
2210.Tg Ox
2211.It Ic \&Ox Op Ar version
2212Format the
2213.Ox
2214version provided as an argument, or a default value
2215if no argument is provided.
2216.Pp
2217Examples:
2218.Dl \&.Ox 4.5
2219.Dl \&.Ox
2220.Pp
2221See also
2222.Ic \&At ,
2223.Ic \&Bsx ,
2224.Ic \&Bx ,
2225.Ic \&Dx ,
2226.Ic \&Fx ,
2227and
2228.Ic \&Nx .
2229.Tg Pa
2230.It Ic \&Pa Ar name ...
2231An absolute or relative file system path, or a file or directory name.
2232If an argument is not provided, the character
2233.Sq \(ti
2234is used as a default.
2235.Pp
2236Examples:
2237.Dl \&.Pa /usr/bin/mandoc
2238.Dl \&.Pa /usr/share/man/man5/mdoc.5
2239.Pp
2240See also
2241.Ic \&Lk .
2242.It Ic \&Pc
2243Close parenthesised context opened by
2244.Ic \&Po .
2245.Tg Pf
2246.It Ic \&Pf Ar prefix macro Op Ar argument ...
2247Removes the space between its argument and the following macro.
2248It is equivalent to:
2249.Pp
2250.D1 Ic \&No Pf \e& Ar prefix Ic \&Ns Ar macro Op Ar argument ...
2251.Pp
2252The
2253.Ar prefix
2254argument is not parsed for macro names or delimiters,
2255but used verbatim as if it were escaped.
2256.Pp
2257Examples:
2258.Dl ".Pf $ Ar variable_name"
2259.Dl ".Pf . Ar macro_name"
2260.Dl ".Pf 0x Ar hex_digits"
2261.Pp
2262See also
2263.Ic \&Ns
2264and
2265.Ic \&Sm .
2266.It Ic \&Po Ar block
2267Multi-line version of
2268.Ic \&Pq .
2269.Tg Pp
2270.It Ic \&Pp
2271Break a paragraph.
2272This will assert vertical space between prior and subsequent macros
2273and/or text.
2274.Pp
2275Paragraph breaks are not needed before or after
2276.Ic \&Sh
2277or
2278.Ic \&Ss
2279macros or before displays
2280.Pq Ic \&Bd Ar line
2281or lists
2282.Pq Ic \&Bl
2283unless the
2284.Fl compact
2285flag is given.
2286.Tg Pq
2287.It Ic \&Pq Ar line
2288Parenthesised enclosure.
2289.Pp
2290See also
2291.Ic \&Po .
2292.It Ic \&Qc
2293Close quoted context opened by
2294.Ic \&Qo .
2295.Tg Ql
2296.It Ic \&Ql Ar line
2297In-line literal display.
2298This can be used for complete command invocations and for multi-word
2299code examples when an indented display is not desired.
2300.Pp
2301See also
2302.Ic \&Dl
2303and
2304.Ic \&Bd
2305.Fl literal .
2306.It Ic \&Qo Ar block
2307Multi-line version of
2308.Ic \&Qq .
2309.Tg Qq
2310.It Ic \&Qq Ar line
2311Encloses its arguments in
2312.Qq typewriter
2313double-quotes.
2314Consider using
2315.Ic \&Dq .
2316.Pp
2317See also
2318.Ic \&Dq ,
2319.Ic \&Sq ,
2320and
2321.Ic \&Qo .
2322.It Ic \&Re
2323Close an
2324.Ic \&Rs
2325block.
2326Does not have any tail arguments.
2327.Tg Rs
2328.It Ic \&Rs
2329Begin a bibliographic
2330.Pq Dq reference
2331block.
2332Does not have any head arguments.
2333The block macro may only contain
2334.Ic \&%A ,
2335.Ic \&%B ,
2336.Ic \&%C ,
2337.Ic \&%D ,
2338.Ic \&%I ,
2339.Ic \&%J ,
2340.Ic \&%N ,
2341.Ic \&%O ,
2342.Ic \&%P ,
2343.Ic \&%Q ,
2344.Ic \&%R ,
2345.Ic \&%T ,
2346.Ic \&%U ,
2347and
2348.Ic \&%V
2349child macros (at least one must be specified).
2350.Pp
2351Examples:
2352.Bd -literal -offset indent -compact
2353\&.Rs
2354\&.%A J. E. Hopcroft
2355\&.%A J. D. Ullman
2356\&.%B Introduction to Automata Theory, Languages, and Computation
2357\&.%I Addison-Wesley
2358\&.%C Reading, Massachusetts
2359\&.%D 1979
2360\&.Re
2361.Ed
2362.Pp
2363If an
2364.Ic \&Rs
2365block is used within a SEE ALSO section, a vertical space is asserted
2366before the rendered output, else the block continues on the current
2367line.
2368.Tg Rv
2369.It Ic \&Rv Fl std Op Ar function ...
2370Insert a standard sentence regarding a function call's return value of 0
2371on success and \-1 on error, with the
2372.Va errno
2373libc global variable set on error.
2374.Pp
2375If
2376.Ar function
2377is not specified, the document's name set by
2378.Ic \&Nm
2379is used.
2380Multiple
2381.Ar function
2382arguments are treated as separate functions.
2383.Pp
2384See also
2385.Ic \&Ex .
2386.It Ic \&Sc
2387Close single-quoted context opened by
2388.Ic \&So .
2389.Tg Sh
2390.It Ic \&Sh Ar TITLE LINE
2391Begin a new section.
2392For a list of conventional manual sections, see
2393.Sx MANUAL STRUCTURE .
2394These sections should be used unless it's absolutely necessary that
2395custom sections be used.
2396.Pp
2397Section names should be unique so that they may be keyed by
2398.Ic \&Sx .
2399Although this macro is parsed, it should not consist of child node or it
2400may not be linked with
2401.Ic \&Sx .
2402.Pp
2403See also
2404.Ic \&Pp ,
2405.Ic \&Ss ,
2406and
2407.Ic \&Sx .
2408.Tg Sm
2409.It Ic \&Sm Op Cm on | off
2410Switches the spacing mode for output generated from macros.
2411.Pp
2412By default, spacing is
2413.Cm on .
2414When switched
2415.Cm off ,
2416no white space is inserted between macro arguments and between the
2417output generated from adjacent macros, but text lines
2418still get normal spacing between words and sentences.
2419.Pp
2420When called without an argument, the
2421.Ic \&Sm
2422macro toggles the spacing mode.
2423Using this is not recommended because it makes the code harder to read.
2424.It Ic \&So Ar block
2425Multi-line version of
2426.Ic \&Sq .
2427.Tg Sq
2428.It Ic \&Sq Ar line
2429Encloses its arguments in
2430.Sq typewriter
2431single-quotes.
2432.Pp
2433See also
2434.Ic \&Dq ,
2435.Ic \&Qq ,
2436and
2437.Ic \&So .
2438.Tg Ss
2439.It Ic \&Ss Ar Title line
2440Begin a new subsection.
2441Unlike with
2442.Ic \&Sh ,
2443there is no convention for the naming of subsections.
2444Except
2445.Em DESCRIPTION ,
2446the conventional sections described in
2447.Sx MANUAL STRUCTURE
2448rarely have subsections.
2449.Pp
2450Sub-section names should be unique so that they may be keyed by
2451.Ic \&Sx .
2452Although this macro is parsed, it should not consist of child node or it
2453may not be linked with
2454.Ic \&Sx .
2455.Pp
2456See also
2457.Ic \&Pp ,
2458.Ic \&Sh ,
2459and
2460.Ic \&Sx .
2461.Tg St
2462.It Ic \&St Fl Ns Ar abbreviation
2463Replace an abbreviation for a standard with the full form.
2464The following standards are recognised.
2465Where multiple lines are given without a blank line in between,
2466they all refer to the same standard, and using the first form
2467is recommended.
2468.Bl -tag -width 1n
2469.It C language standards
2470.Pp
2471.Bl -tag -width "-p1003.1g-2000" -compact
2472.It \-ansiC
2473.St -ansiC
2474.It \-ansiC-89
2475.St -ansiC-89
2476.It \-isoC
2477.St -isoC
2478.It \-isoC-90
2479.St -isoC-90
2480.br
2481The original C standard.
2482.Pp
2483.It \-isoC-amd1
2484.St -isoC-amd1
2485.Pp
2486.It \-isoC-tcor1
2487.St -isoC-tcor1
2488.Pp
2489.It \-isoC-tcor2
2490.St -isoC-tcor2
2491.Pp
2492.It \-isoC-99
2493.St -isoC-99
2494.br
2495The second major version of the C language standard.
2496.Pp
2497.It \-isoC-2011
2498.St -isoC-2011
2499.br
2500The third major version of the C language standard.
2501.El
2502.It POSIX.1 before the Single UNIX Specification
2503.Pp
2504.Bl -tag -width "-p1003.1g-2000" -compact
2505.It \-p1003.1-88
2506.St -p1003.1-88
2507.It \-p1003.1
2508.St -p1003.1
2509.br
2510The original POSIX standard, based on ANSI C.
2511.Pp
2512.It \-p1003.1-90
2513.St -p1003.1-90
2514.It \-iso9945-1-90
2515.St -iso9945-1-90
2516.br
2517The first update of POSIX.1.
2518.Pp
2519.It \-p1003.1b-93
2520.St -p1003.1b-93
2521.It \-p1003.1b
2522.St -p1003.1b
2523.br
2524Real-time extensions.
2525.Pp
2526.It \-p1003.1c-95
2527.St -p1003.1c-95
2528.br
2529POSIX thread interfaces.
2530.Pp
2531.It \-p1003.1i-95
2532.St -p1003.1i-95
2533.br
2534Technical Corrigendum.
2535.Pp
2536.It \-p1003.1-96
2537.St -p1003.1-96
2538.It \-iso9945-1-96
2539.St -iso9945-1-96
2540.br
2541Includes POSIX.1-1990, 1b, 1c, and 1i.
2542.El
2543.It X/Open Portability Guide version 4 and related standards
2544.Pp
2545.Bl -tag -width "-p1003.1g-2000" -compact
2546.It \-xpg3
2547.St -xpg3
2548.br
2549An XPG4 precursor, published in 1989.
2550.Pp
2551.It \-p1003.2
2552.St -p1003.2
2553.It \-p1003.2-92
2554.St -p1003.2-92
2555.It \-iso9945-2-93
2556.St -iso9945-2-93
2557.br
2558An XCU4 precursor.
2559.Pp
2560.It \-p1003.2a-92
2561.St -p1003.2a-92
2562.br
2563Updates to POSIX.2.
2564.Pp
2565.It \-xpg4
2566.St -xpg4
2567.br
2568Based on POSIX.1 and POSIX.2, published in 1992.
2569.El
2570.It Single UNIX Specification version 1 and related standards
2571.Pp
2572.Bl -tag -width "-p1003.1g-2000" -compact
2573.It \-susv1
2574.St -susv1
2575.It \-xpg4.2
2576.St -xpg4.2
2577.br
2578This standard was published in 1994.
2579It was used as the basis for UNIX 95 certification.
2580The following three refer to parts of it.
2581.Pp
2582.It \-xsh4.2
2583.St -xsh4.2
2584.Pp
2585.It \-xcurses4.2
2586.St -xcurses4.2
2587.Pp
2588.It \-p1003.1g-2000
2589.St -p1003.1g-2000
2590.br
2591Networking APIs, including sockets.
2592.Pp
2593.It \-svid4
2594.St -svid4 ,
2595.br
2596Published in 1995.
2597.El
2598.It Single UNIX Specification version 2 and related standards
2599.Pp
2600.Bl -tag -width "-p1003.1g-2000" -compact
2601.It \-susv2
2602.St -susv2
2603This Standard was published in 1997
2604and is also called X/Open Portability Guide version 5.
2605It was used as the basis for UNIX 98 certification.
2606The following refer to parts of it.
2607.Pp
2608.It \-xbd5
2609.St -xbd5
2610.Pp
2611.It \-xsh5
2612.St -xsh5
2613.Pp
2614.It \-xcu5
2615.St -xcu5
2616.Pp
2617.It \-xns5
2618.St -xns5
2619.It \-xns5.2
2620.St -xns5.2
2621.El
2622.It Single UNIX Specification version 3
2623.Pp
2624.Bl -tag -width "-p1003.1-2001" -compact
2625.It \-p1003.1-2001
2626.St -p1003.1-2001
2627.It \-susv3
2628.St -susv3
2629.br
2630This standard is based on C99, SUSv2, POSIX.1-1996, 1d, and 1j.
2631It is also called X/Open Portability Guide version 6.
2632It is used as the basis for UNIX 03 certification.
2633.Pp
2634.It \-p1003.1-2004
2635.St -p1003.1-2004
2636.br
2637The second and last Technical Corrigendum.
2638.El
2639.It Single UNIX Specification version 4
2640.Pp
2641.Bl -tag -width "-p1003.1g-2000" -compact
2642.It \-p1003.1-2008
2643.St -p1003.1-2008
2644.It \-susv4
2645.St -susv4
2646.br
2647This standard is also called
2648X/Open Portability Guide version 7.
2649.El
2650.It Other standards
2651.Pp
2652.Bl -tag -width "-p1003.1g-2000" -compact
2653.It \-ieee754
2654.St -ieee754
2655.br
2656Floating-point arithmetic.
2657.Pp
2658.It \-iso8601
2659.St -iso8601
2660.br
2661Representation of dates and times, published in 1988.
2662.Pp
2663.It \-iso8802-3
2664.St -iso8802-3
2665.br
2666Ethernet local area networks.
2667.Pp
2668.It \-ieee1275-94
2669.St -ieee1275-94
2670.El
2671.El
2672.Tg Sx
2673.It Ic \&Sx Ar Title line
2674Reference a section or subsection in the same manual page.
2675The referenced section or subsection name must be identical to the
2676enclosed argument, including whitespace.
2677.Pp
2678Examples:
2679.Dl \&.Sx MANUAL STRUCTURE
2680.Pp
2681See also
2682.Ic \&Sh
2683and
2684.Ic \&Ss .
2685.Tg Sy
2686.It Ic \&Sy Ar word ...
2687Request a boldface font.
2688.Pp
2689This is most often used to indicate importance or seriousness (not to be
2690confused with stress emphasis, see
2691.Ic \&Em ) .
2692When none of the semantic macros fit, it is also adequate for syntax
2693elements that have to be given or that appear verbatim.
2694.Pp
2695Examples:
2696.Bd -literal -compact -offset indent
2697\&.Sy Warning :
2698If
2699\&.Sy s
2700appears in the owner permissions, set-user-ID mode is set.
2701This utility replaces the former
2702\&.Sy dumpdir
2703program.
2704.Ed
2705.Pp
2706See also
2707.Ic \&Em ,
2708.Ic \&No ,
2709and
2710.Ic \&Ql .
2711.Tg Ta
2712.It Ic \&Ta
2713Table cell separator in
2714.Ic \&Bl Fl column
2715lists; can only be used below
2716.Ic \&It .
2717.Tg Tg
2718.It Ic \&Tg Op Ar term
2719Announce that the next input line starts a definition of the
2720.Ar term .
2721This macro must appear alone on its own input line.
2722The argument defaults to the first argument of the first macro
2723on the next line.
2724The argument may not contain whitespace characters, not even when it is quoted.
2725This macro is a
2726.Xr mandoc 1
2727extension and is typically ignored by other formatters.
2728.Pp
2729When viewing terminal output with
2730.Xr less 1 ,
2731the interactive
2732.Ic :t
2733command can be used to go to the definition of the
2734.Ar term
2735as described for the
2736.Ev MANPAGER
2737variable in
2738.Xr man 1 ;
2739when producing HTML output, a fragment identifier
2740.Pq Ic id No attribute
2741is generated, to be used for deep linking to this place of the document.
2742.Pp
2743In most cases, adding a
2744.Ic \&Tg
2745macro would be redundant because
2746.Xr mandoc 1
2747is able to automatically tag most definitions.
2748This macro is intended for cases where automatic tagging of a
2749.Ar term
2750is unsatisfactory, for example if a definition is not tagged
2751automatically (false negative) or if places are tagged that do
2752not define the
2753.Ar term
2754(false positives).
2755When there is at least one
2756.Ic \&Tg
2757macro for a
2758.Ar term ,
2759no other places are automatically marked as definitions of that
2760.Ar term .
2761.It Ic \&Tn Ar word ...
2762Supported only for compatibility, do not use this in new manuals.
2763Even though the macro name
2764.Pq Dq tradename
2765suggests a semantic function, historic usage is inconsistent, mostly
2766using it as a presentation-level macro to request a small caps font.
2767.It Ic \&Ud
2768Supported only for compatibility, do not use this in new manuals.
2769Prints out
2770.Dq currently under development.
2771.It Ic \&Ux
2772Supported only for compatibility, do not use this in new manuals.
2773Prints out
2774.Dq Ux .
2775.Tg Va
2776.It Ic \&Va Oo Ar type Oc Ar identifier ...
2777A variable name.
2778.Pp
2779Examples:
2780.Dl \&.Va foo
2781.Dl \&.Va const char *bar ;
2782.Pp
2783For function arguments and parameters, use
2784.Ic \&Fa
2785instead.
2786For declarations of global variables in the
2787.Em SYNOPSIS
2788section, use
2789.Ic \&Vt .
2790.Tg Vt
2791.It Ic \&Vt Ar type Op Ar identifier
2792A variable type.
2793.Pp
2794This is also used for indicating global variables in the
2795.Em SYNOPSIS
2796section, in which case a variable name is also specified.
2797Note that it accepts
2798.Sx Block partial-implicit
2799syntax when invoked as the first macro on an input line in the
2800.Em SYNOPSIS
2801section, else it accepts ordinary
2802.Sx In-line
2803syntax.
2804In the former case, this macro starts a new output line,
2805and a blank line is inserted in front if there is a preceding
2806function definition or include directive.
2807.Pp
2808Examples:
2809.Dl \&.Vt unsigned char
2810.Dl \&.Vt extern const char * const sys_signame[] \&;
2811.Pp
2812For parameters in function prototypes, use
2813.Ic \&Fa
2814instead, for function return types
2815.Ic \&Ft ,
2816and for variable names outside the
2817.Em SYNOPSIS
2818section
2819.Ic \&Va ,
2820even when including a type with the name.
2821See also
2822.Sx MANUAL STRUCTURE .
2823.It Ic \&Xc
2824Close a scope opened by
2825.Ic \&Xo .
2826.It Ic \&Xo Ar block
2827Extend the header of an
2828.Ic \&It
2829macro or the body of a partial-implicit block macro
2830beyond the end of the input line.
2831This macro originally existed to work around the 9-argument limit
2832of historic
2833.Xr mandoc_roff 7 .
2834.Tg Xr
2835.It Ic \&Xr Ar name section
2836Link to another manual
2837.Pq Qq cross-reference .
2838.Pp
2839Cross reference the
2840.Ar name
2841and
2842.Ar section
2843number of another man page.
2844.Pp
2845Examples:
2846.Dl \&.Xr mandoc 1
2847.Dl \&.Xr mandoc 1 \&;
2848.Dl \&.Xr mandoc 1 \&Ns s behaviour
2849.El
2850.Sh MACRO SYNTAX
2851The syntax of a macro depends on its classification.
2852In this section,
2853.Sq \-arg
2854refers to macro arguments, which may be followed by zero or more
2855.Sq parm
2856parameters;
2857.Sq \&Yo
2858opens the scope of a macro; and if specified,
2859.Sq \&Yc
2860closes it out.
2861.Pp
2862The
2863.Em Callable
2864column indicates that the macro may also be called by passing its name
2865as an argument to another macro.
2866For example,
2867.Sq \&.Op \&Fl O \&Ar file
2868produces
2869.Sq Op Fl O Ar file .
2870To prevent a macro call and render the macro name literally,
2871escape it by prepending a zero-width space,
2872.Sq \e& .
2873For example,
2874.Sq \&Op \e&Fl O
2875produces
2876.Sq Op \&Fl O .
2877If a macro is not callable but its name appears as an argument
2878to another macro, it is interpreted as opaque text.
2879For example,
2880.Sq \&.Fl \&Sh
2881produces
2882.Sq Fl \&Sh .
2883.Pp
2884The
2885.Em Parsed
2886column indicates whether the macro may call other macros by receiving
2887their names as arguments.
2888If a macro is not parsed but the name of another macro appears
2889as an argument, it is interpreted as opaque text.
2890.Pp
2891The
2892.Em Scope
2893column, if applicable, describes closure rules.
2894.Ss Block full-explicit
2895Multi-line scope closed by an explicit closing macro.
2896All macros contains bodies; only
2897.Ic \&Bf
2898and
2899.Pq optionally
2900.Ic \&Bl
2901contain a head.
2902.Bd -literal -offset indent
2903\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
2904\(lBbody...\(rB
2905\&.Yc
2906.Ed
2907.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXX" -offset indent
2908.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2909.It Ic \&Bd  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ed
2910.It Ic \&Bf  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ef
2911.It Ic \&Bk  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ek
2912.It Ic \&Bl  Ta    \&No     Ta    \&No     Ta    closed by Ic \&El
2913.It Ic \&Ed  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bd
2914.It Ic \&Ef  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bf
2915.It Ic \&Ek  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bk
2916.It Ic \&El  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bl
2917.El
2918.Ss Block full-implicit
2919Multi-line scope closed by end-of-file or implicitly by another macro.
2920All macros have bodies; some
2921.Po
2922.Ic \&It Fl bullet ,
2923.Fl hyphen ,
2924.Fl dash ,
2925.Fl enum ,
2926.Fl item
2927.Pc
2928don't have heads; only one
2929.Po
2930.Ic \&It
2931in
2932.Ic \&Bl Fl column
2933.Pc
2934has multiple heads.
2935.Bd -literal -offset indent
2936\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB
2937\(lBbody...\(rB
2938.Ed
2939.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXXXXXXXXX" -offset indent
2940.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2941.It Ic \&It Ta \&No Ta Yes  Ta closed by Ic \&It , Ic \&El
2942.It Ic \&Nd Ta \&No Ta \&No Ta closed by Ic \&Sh
2943.It Ic \&Nm Ta \&No Ta Yes  Ta closed by Ic \&Nm , Ic \&Sh , Ic \&Ss
2944.It Ic \&Sh Ta \&No Ta Yes  Ta closed by Ic \&Sh
2945.It Ic \&Ss Ta \&No Ta Yes  Ta closed by Ic \&Sh , Ic \&Ss
2946.El
2947.Pp
2948Note that the
2949.Ic \&Nm
2950macro is a
2951.Sx Block full-implicit
2952macro only when invoked as the first macro
2953in a
2954.Em SYNOPSIS
2955section line, else it is
2956.Sx In-line .
2957.Ss Block partial-explicit
2958Like block full-explicit, but also with single-line scope.
2959Each has at least a body and, in limited circumstances, a head
2960.Po
2961.Ic \&Fo ,
2962.Ic \&Eo
2963.Pc
2964and/or tail
2965.Pq Ic \&Ec .
2966.Bd -literal -offset indent
2967\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
2968\(lBbody...\(rB
2969\&.Yc \(lBtail...\(rB
2970
2971\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \
2972\(lBbody...\(rB \&Yc \(lBtail...\(rB
2973.Ed
2974.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
2975.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2976.It Ic \&Ac  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Ao
2977.It Ic \&Ao  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Ac
2978.It Ic \&Bc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Bo
2979.It Ic \&Bo  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Bc
2980.It Ic \&Brc Ta    Yes      Ta    Yes      Ta    opened by Ic \&Bro
2981.It Ic \&Bro Ta    Yes      Ta    Yes      Ta    closed by Ic \&Brc
2982.It Ic \&Dc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Do
2983.It Ic \&Do  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Dc
2984.It Ic \&Ec  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Eo
2985.It Ic \&Eo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Ec
2986.It Ic \&Fc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Fo
2987.It Ic \&Fo  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Fc
2988.It Ic \&Oc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Oo
2989.It Ic \&Oo  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Oc
2990.It Ic \&Pc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Po
2991.It Ic \&Po  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Pc
2992.It Ic \&Qc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Oo
2993.It Ic \&Qo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Oc
2994.It Ic \&Re  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Rs
2995.It Ic \&Rs  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Re
2996.It Ic \&Sc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&So
2997.It Ic \&So  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Sc
2998.It Ic \&Xc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Xo
2999.It Ic \&Xo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Xc
3000.El
3001.Ss Block partial-implicit
3002Like block full-implicit, but with single-line scope closed by the
3003end of the line.
3004.Bd -literal -offset indent
3005\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB
3006.Ed
3007.Bl -column "MacroX" "CallableX" "ParsedX" -offset indent
3008.It Em Macro Ta Em Callable Ta Em Parsed
3009.It Ic \&Aq  Ta    Yes      Ta    Yes
3010.It Ic \&Bq  Ta    Yes      Ta    Yes
3011.It Ic \&Brq Ta    Yes      Ta    Yes
3012.It Ic \&D1  Ta    \&No     Ta    \&Yes
3013.It Ic \&Dl  Ta    \&No     Ta    Yes
3014.It Ic \&Dq  Ta    Yes      Ta    Yes
3015.It Ic \&En  Ta    Yes      Ta    Yes
3016.It Ic \&Op  Ta    Yes      Ta    Yes
3017.It Ic \&Pq  Ta    Yes      Ta    Yes
3018.It Ic \&Ql  Ta    Yes      Ta    Yes
3019.It Ic \&Qq  Ta    Yes      Ta    Yes
3020.It Ic \&Sq  Ta    Yes      Ta    Yes
3021.It Ic \&Vt  Ta    Yes      Ta    Yes
3022.El
3023.Pp
3024Note that the
3025.Ic \&Vt
3026macro is a
3027.Sx Block partial-implicit
3028only when invoked as the first macro
3029in a
3030.Em SYNOPSIS
3031section line, else it is
3032.Sx In-line .
3033.Ss Special block macro
3034The
3035.Ic \&Ta
3036macro can only be used below
3037.Ic \&It
3038in
3039.Ic \&Bl Fl column
3040lists.
3041It delimits blocks representing table cells;
3042these blocks have bodies, but no heads.
3043.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
3044.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
3045.It Ic \&Ta  Ta    Yes      Ta    Yes    Ta closed by Ic \&Ta , Ic \&It
3046.El
3047.Ss In-line
3048Closed by the end of the line, fixed argument lengths,
3049and/or subsequent macros.
3050In-line macros have only text children.
3051If a number (or inequality) of arguments is
3052.Pq n ,
3053then the macro accepts an arbitrary number of arguments.
3054.Bd -literal -offset indent
3055\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB \(lBres...\(rB
3056
3057\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc...
3058
3059\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
3060.Ed
3061.Bl -column "MacroX" "CallableX" "ParsedX" "Arguments" -offset indent
3062.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Arguments
3063.It Ic \&%A  Ta    \&No     Ta    \&No     Ta    >0
3064.It Ic \&%B  Ta    \&No     Ta    \&No     Ta    >0
3065.It Ic \&%C  Ta    \&No     Ta    \&No     Ta    >0
3066.It Ic \&%D  Ta    \&No     Ta    \&No     Ta    >0
3067.It Ic \&%I  Ta    \&No     Ta    \&No     Ta    >0
3068.It Ic \&%J  Ta    \&No     Ta    \&No     Ta    >0
3069.It Ic \&%N  Ta    \&No     Ta    \&No     Ta    >0
3070.It Ic \&%O  Ta    \&No     Ta    \&No     Ta    >0
3071.It Ic \&%P  Ta    \&No     Ta    \&No     Ta    >0
3072.It Ic \&%Q  Ta    \&No     Ta    \&No     Ta    >0
3073.It Ic \&%R  Ta    \&No     Ta    \&No     Ta    >0
3074.It Ic \&%T  Ta    \&No     Ta    \&No     Ta    >0
3075.It Ic \&%U  Ta    \&No     Ta    \&No     Ta    >0
3076.It Ic \&%V  Ta    \&No     Ta    \&No     Ta    >0
3077.It Ic \&Ad  Ta    Yes      Ta    Yes      Ta    >0
3078.It Ic \&An  Ta    Yes      Ta    Yes      Ta    >0
3079.It Ic \&Ap  Ta    Yes      Ta    Yes      Ta    0
3080.It Ic \&Ar  Ta    Yes      Ta    Yes      Ta    n
3081.It Ic \&At  Ta    Yes      Ta    Yes      Ta    1
3082.It Ic \&Bsx Ta    Yes      Ta    Yes      Ta    n
3083.It Ic \&Bt  Ta    \&No     Ta    \&No     Ta    0
3084.It Ic \&Bx  Ta    Yes      Ta    Yes      Ta    n
3085.It Ic \&Cd  Ta    Yes      Ta    Yes      Ta    >0
3086.It Ic \&Cm  Ta    Yes      Ta    Yes      Ta    >0
3087.It Ic \&Db  Ta    \&No     Ta    \&No     Ta    1
3088.It Ic \&Dd  Ta    \&No     Ta    \&No     Ta    n
3089.It Ic \&Dt  Ta    \&No     Ta    \&No     Ta    n
3090.It Ic \&Dv  Ta    Yes      Ta    Yes      Ta    >0
3091.It Ic \&Dx  Ta    Yes      Ta    Yes      Ta    n
3092.It Ic \&Em  Ta    Yes      Ta    Yes      Ta    >0
3093.It Ic \&Er  Ta    Yes      Ta    Yes      Ta    >0
3094.It Ic \&Es  Ta    Yes      Ta    Yes      Ta    2
3095.It Ic \&Ev  Ta    Yes      Ta    Yes      Ta    >0
3096.It Ic \&Ex  Ta    \&No     Ta    \&No     Ta    n
3097.It Ic \&Fa  Ta    Yes      Ta    Yes      Ta    >0
3098.It Ic \&Fd  Ta    \&No     Ta    \&No     Ta    >0
3099.It Ic \&Fl  Ta    Yes      Ta    Yes      Ta    n
3100.It Ic \&Fn  Ta    Yes      Ta    Yes      Ta    >0
3101.It Ic \&Fr  Ta    Yes      Ta    Yes      Ta    >0
3102.It Ic \&Ft  Ta    Yes      Ta    Yes      Ta    >0
3103.It Ic \&Fx  Ta    Yes      Ta    Yes      Ta    n
3104.It Ic \&Hf  Ta    \&No     Ta    \&No     Ta    n
3105.It Ic \&Ic  Ta    Yes      Ta    Yes      Ta    >0
3106.It Ic \&In  Ta    \&No     Ta    \&No     Ta    1
3107.It Ic \&Lb  Ta    \&No     Ta    \&No     Ta    1
3108.It Ic \&Li  Ta    Yes      Ta    Yes      Ta    >0
3109.It Ic \&Lk  Ta    Yes      Ta    Yes      Ta    >0
3110.It Ic \&Lp  Ta    \&No     Ta    \&No     Ta    0
3111.It Ic \&Ms  Ta    Yes      Ta    Yes      Ta    >0
3112.It Ic \&Mt  Ta    Yes      Ta    Yes      Ta    >0
3113.It Ic \&Nm  Ta    Yes      Ta    Yes      Ta    n
3114.It Ic \&No  Ta    Yes      Ta    Yes      Ta    >0
3115.It Ic \&Ns  Ta    Yes      Ta    Yes      Ta    0
3116.It Ic \&Nx  Ta    Yes      Ta    Yes      Ta    n
3117.It Ic \&Os  Ta    \&No     Ta    \&No     Ta    n
3118.It Ic \&Ot  Ta    Yes      Ta    Yes      Ta    >0
3119.It Ic \&Ox  Ta    Yes      Ta    Yes      Ta    n
3120.It Ic \&Pa  Ta    Yes      Ta    Yes      Ta    n
3121.It Ic \&Pf  Ta    Yes      Ta    Yes      Ta    1
3122.It Ic \&Pp  Ta    \&No     Ta    \&No     Ta    0
3123.It Ic \&Rv  Ta    \&No     Ta    \&No     Ta    n
3124.It Ic \&Sm  Ta    \&No     Ta    \&No     Ta    <2
3125.It Ic \&St  Ta    \&No     Ta    Yes      Ta    1
3126.It Ic \&Sx  Ta    Yes      Ta    Yes      Ta    >0
3127.It Ic \&Sy  Ta    Yes      Ta    Yes      Ta    >0
3128.It Ic \&Tg  Ta    \&No     Ta    \&No     Ta    <2
3129.It Ic \&Tn  Ta    Yes      Ta    Yes      Ta    >0
3130.It Ic \&Ud  Ta    \&No     Ta    \&No     Ta    0
3131.It Ic \&Ux  Ta    Yes      Ta    Yes      Ta    n
3132.It Ic \&Va  Ta    Yes      Ta    Yes      Ta    n
3133.It Ic \&Vt  Ta    Yes      Ta    Yes      Ta    >0
3134.It Ic \&Xr  Ta    Yes      Ta    Yes      Ta    2
3135.El
3136.Ss Delimiters
3137When a macro argument consists of one single input character
3138considered as a delimiter, the argument gets special handling.
3139This does not apply when delimiters appear in arguments containing
3140more than one character.
3141Consequently, to prevent special handling and just handle it
3142like any other argument, a delimiter can be escaped by prepending
3143a zero-width space
3144.Pq Sq \e& .
3145In text lines, delimiters never need escaping, but may be used
3146as normal punctuation.
3147.Pp
3148For many macros, when the leading arguments are opening delimiters,
3149these delimiters are put before the macro scope,
3150and when the trailing arguments are closing delimiters,
3151these delimiters are put after the macro scope.
3152Spacing is suppressed after opening delimiters
3153and before closing delimiters.
3154For example,
3155.Pp
3156.D1 Pf \. \&Aq "( [ word ] ) ."
3157.Pp
3158renders as:
3159.Pp
3160.D1 Aq ( [ word ] ) .
3161.Pp
3162Opening delimiters are:
3163.Pp
3164.Bl -tag -width Ds -offset indent -compact
3165.It \&(
3166left parenthesis
3167.It \&[
3168left bracket
3169.El
3170.Pp
3171Closing delimiters are:
3172.Pp
3173.Bl -tag -width Ds -offset indent -compact
3174.It \&.
3175period
3176.It \&,
3177comma
3178.It \&:
3179colon
3180.It \&;
3181semicolon
3182.It \&)
3183right parenthesis
3184.It \&]
3185right bracket
3186.It \&?
3187question mark
3188.It \&!
3189exclamation mark
3190.El
3191.Pp
3192Note that even a period preceded by a backslash
3193.Pq Sq \e.\&
3194gets this special handling; use
3195.Sq \e&.\&
3196to prevent that.
3197.Pp
3198Many in-line macros interrupt their scope when they encounter
3199delimiters, and resume their scope when more arguments follow that
3200are not delimiters.
3201For example,
3202.Pp
3203.D1 Pf \. \&Fl "a ( b | c \e*(Ba d ) e"
3204.Pp
3205renders as:
3206.Pp
3207.D1 Fl a ( b | c \*(Ba d ) e
3208.Pp
3209This applies to both opening and closing delimiters,
3210and also to the middle delimiter, which does not suppress spacing:
3211.Pp
3212.Bl -tag -width Ds -offset indent -compact
3213.It \&|
3214vertical bar
3215.El
3216.Pp
3217As a special case, the predefined string \e*(Ba is handled and rendered
3218in the same way as a plain
3219.Sq \&|
3220character.
3221Using this predefined string is not recommended in new manuals.
3222.Pp
3223Appending a zero-width space
3224.Pq Sq \e&
3225to the end of an input line is also useful to prevent the interpretation
3226of a trailing period, exclamation or question mark as the end of a
3227sentence, for example when an abbreviation happens to occur
3228at the end of a text or macro input line.
3229.Ss Font handling
3230In
3231.Nm
3232documents, usage of semantic markup is recommended in order to have
3233proper fonts automatically selected; only when no fitting semantic markup
3234is available, consider falling back to
3235.Sx Physical markup
3236macros.
3237Whenever any
3238.Nm
3239macro switches the
3240.Xr mandoc_roff 7
3241font mode, it will automatically restore the previous font when exiting
3242its scope.
3243Manually switching the font using the
3244.Xr mandoc_roff 7
3245.Ql \ef
3246font escape sequences is never required.
3247.Sh COMPATIBILITY
3248This section provides an incomplete list of compatibility issues
3249between mandoc and GNU troff
3250.Pq Qq groff .
3251.Pp
3252The following problematic behaviour is found in groff:
3253.Pp
3254.Bl -dash -compact
3255.It
3256.Ic \&Pa
3257does not format its arguments when used in the FILES section under
3258certain list types.
3259.It
3260.Ic \&Ta
3261can only be called by other macros, but not at the beginning of a line.
3262.It
3263.Sq \ef
3264.Pq font face
3265and
3266.Sq \eF
3267.Pq font family face
3268.Sx Text Decoration
3269escapes behave irregularly when specified within line-macro scopes.
3270.It
3271Negative scaling units return to prior lines.
3272Instead, mandoc truncates them to zero.
3273.El
3274.Pp
3275The following features are unimplemented in mandoc:
3276.Pp
3277.Bl -dash -compact
3278.It
3279.Ic \&Bd Fl file Ar file
3280is unsupported for security reasons.
3281.It
3282.Ic \&Bd
3283.Fl filled
3284does not adjust the right margin, but is an alias for
3285.Ic \&Bd
3286.Fl ragged .
3287.It
3288.Ic \&Bd
3289.Fl literal
3290does not use a literal font, but is an alias for
3291.Ic \&Bd
3292.Fl unfilled .
3293.It
3294.Ic \&Bd
3295.Fl offset Cm center
3296and
3297.Fl offset Cm right
3298don't work.
3299Groff does not implement centered and flush-right rendering either,
3300but produces large indentations.
3301.El
3302.Sh SEE ALSO
3303.Xr man 1 ,
3304.Xr mandoc 1 ,
3305.Xr eqn 7 ,
3306.Xr man 7 ,
3307.Xr mandoc_char 7 ,
3308.Xr mandoc_roff 7 ,
3309.Xr tbl 7
3310.Pp
3311The web page
3312.Lk https://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language"
3313provides a few tutorial-style pages for beginners, an extensive style
3314guide for advanced authors, and an alphabetic index helping to choose
3315the best macros for various kinds of content.
3316.Pp
3317The manual page
3318.Lk https://man.voidlinux.org/groff_mdoc "groff_mdoc(4)"
3319contained in the
3320.Dq groff
3321package documents exactly the same language in a somewhat different style.
3322.Sh HISTORY
3323The
3324.Nm
3325language first appeared as a troff macro package in
3326.Bx 4.4 .
3327It was later significantly updated by Werner Lemberg and Ruslan Ermilov
3328in groff-1.17.
3329The standalone implementation that is part of the
3330.Xr mandoc 1
3331utility written by Kristaps Dzonsons appeared in
3332.Ox 4.6 .
3333.Sh AUTHORS
3334The
3335.Nm
3336reference was written by
3337.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
3338