xref: /openbsd/share/man/man7/mdoc.7 (revision 73471bf0)
1.\"	$OpenBSD: mdoc.7,v 1.180 2021/12/05 15:53:46 jmc 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.Dd $Mdocdate: December 5 2021 $
19.Dt MDOC 7
20.Os
21.Sh NAME
22.Nm mdoc
23.Nd semantic markup language for formatting manual pages
24.Sh DESCRIPTION
25The
26.Nm mdoc
27language supports authoring of manual pages for the
28.Xr man 1
29utility by allowing semantic annotations of words, phrases,
30page sections and complete manual pages.
31Such annotations are used by formatting tools to achieve a uniform
32presentation across all manuals written in
33.Nm ,
34and to support hyperlinking if supported by the output medium.
35.Pp
36This reference document describes the structure of manual pages
37and the syntax and usage of the
38.Nm
39language.
40The reference implementation of a parsing and formatting tool is
41.Xr mandoc 1 ;
42the
43.Sx COMPATIBILITY
44section describes compatibility with other implementations.
45.Pp
46In an
47.Nm
48document, lines beginning with the control character
49.Sq \&.
50are called
51.Dq macro lines .
52The first word is the macro name.
53It consists of two or three letters.
54Most macro names begin with a capital letter.
55For a list of available macros, see
56.Sx MACRO OVERVIEW .
57The words following the macro name are arguments to the macro, optionally
58including the names of other, callable macros; see
59.Sx MACRO SYNTAX
60for details.
61.Pp
62Lines not beginning with the control character are called
63.Dq text lines .
64They provide free-form text to be printed; the formatting of the text
65depends on the respective processing context:
66.Bd -literal -offset indent
67\&.Sh Macro lines change control state.
68Text lines are interpreted within the current state.
69.Ed
70.Pp
71Many aspects of the basic syntax of the
72.Nm
73language are based on the
74.Xr roff 7
75language; see the
76.Em LANGUAGE SYNTAX
77and
78.Em MACRO SYNTAX
79sections in the
80.Xr roff 7
81manual for details, in particular regarding
82comments, escape sequences, whitespace, and quoting.
83However, using
84.Xr roff 7
85requests in
86.Nm
87documents is discouraged;
88.Xr mandoc 1
89supports some of them merely for backward compatibility.
90.Sh MANUAL STRUCTURE
91A well-formed
92.Nm
93document consists of a document prologue followed by one or more
94sections.
95.Pp
96The prologue, which consists of the
97.Ic \&Dd ,
98.Ic \&Dt ,
99and
100.Ic \&Os
101macros in that order, is required for every document.
102.Pp
103The first section (sections are denoted by
104.Ic \&Sh )
105must be the NAME section, consisting of at least one
106.Ic \&Nm
107followed by
108.Ic \&Nd .
109.Pp
110Following that, convention dictates specifying at least the
111.Em SYNOPSIS
112and
113.Em DESCRIPTION
114sections, although this varies between manual sections.
115.Pp
116The following is a well-formed skeleton
117.Nm
118file for a utility
119.Qq progname :
120.Bd -literal -offset indent
121\&.Dd $\&Mdocdate$
122\&.Dt PROGNAME section
123\&.Os
124\&.Sh NAME
125\&.Nm progname
126\&.Nd one line about what it does
127\&.\e\(dq .Sh LIBRARY
128\&.\e\(dq For sections 2, 3, and 9 only.
129\&.\e\(dq Not used in OpenBSD.
130\&.Sh SYNOPSIS
131\&.Nm progname
132\&.Op Fl options
133\&.Ar
134\&.Sh DESCRIPTION
135The
136\&.Nm
137utility processes files ...
138\&.\e\(dq .Sh CONTEXT
139\&.\e\(dq For section 9 functions only.
140\&.\e\(dq .Sh IMPLEMENTATION NOTES
141\&.\e\(dq Not used in OpenBSD.
142\&.\e\(dq .Sh RETURN VALUES
143\&.\e\(dq For sections 2, 3, and 9 function return values only.
144\&.\e\(dq .Sh ENVIRONMENT
145\&.\e\(dq For sections 1, 6, 7, and 8 only.
146\&.\e\(dq .Sh FILES
147\&.\e\(dq .Sh EXIT STATUS
148\&.\e\(dq For sections 1, 6, and 8 only.
149\&.\e\(dq .Sh EXAMPLES
150\&.\e\(dq .Sh DIAGNOSTICS
151\&.\e\(dq For sections 1, 4, 6, 7, 8, and 9 printf/stderr messages only.
152\&.\e\(dq .Sh ERRORS
153\&.\e\(dq For sections 2, 3, 4, and 9 errno settings only.
154\&.\e\(dq .Sh SEE ALSO
155\&.\e\(dq .Xr foobar 1
156\&.\e\(dq .Sh STANDARDS
157\&.\e\(dq .Sh HISTORY
158\&.\e\(dq .Sh AUTHORS
159\&.\e\(dq .Sh CAVEATS
160\&.\e\(dq .Sh BUGS
161\&.\e\(dq .Sh SECURITY CONSIDERATIONS
162\&.\e\(dq Not used in OpenBSD.
163.Ed
164.Pp
165The sections in an
166.Nm
167document are conventionally ordered as they appear above.
168Sections should be composed as follows:
169.Bl -ohang -offset Ds
170.It Em NAME
171The name(s) and a one line description of the documented material.
172The syntax for this as follows:
173.Bd -literal -offset indent
174\&.Nm name0 ,
175\&.Nm name1 ,
176\&.Nm name2
177\&.Nd a one line description
178.Ed
179.Pp
180Multiple
181.Sq \&Nm
182names should be separated by commas.
183.Pp
184The
185.Ic \&Nm
186macro(s) must precede the
187.Ic \&Nd
188macro.
189.Pp
190See
191.Ic \&Nm
192and
193.Ic \&Nd .
194.It Em LIBRARY
195The name of the library containing the documented material, which is
196assumed to be a function in a section 2, 3, or 9 manual.
197The syntax for this is as follows:
198.Bd -literal -offset indent
199\&.Lb libarm
200.Ed
201.Pp
202See
203.Ic \&Lb .
204.It Em SYNOPSIS
205Documents the utility invocation syntax, function call syntax, or device
206configuration.
207.Pp
208For the first, utilities (sections 1, 6, and 8), this is
209generally structured as follows:
210.Bd -literal -offset indent
211\&.Nm bar
212\&.Op Fl v
213\&.Op Fl o Ar file
214\&.Op Ar
215\&.Nm foo
216\&.Op Fl v
217\&.Op Fl o Ar file
218\&.Op Ar
219.Ed
220.Pp
221Commands should be ordered alphabetically.
222.Pp
223For the second, function calls (sections 2, 3, 9):
224.Bd -literal -offset indent
225\&.In header.h
226\&.Vt extern const char *global;
227\&.Ft "char *"
228\&.Fn foo "const char *src"
229\&.Ft "char *"
230\&.Fn bar "const char *src"
231.Ed
232.Pp
233Ordering of
234.Ic \&In ,
235.Ic \&Vt ,
236.Ic \&Fn ,
237and
238.Ic \&Fo
239macros should follow C header-file conventions.
240.Pp
241And for the third, configurations (section 4):
242.Bd -literal -offset indent
243\&.Cd \(dqit* at isa? port 0x2e\(dq
244\&.Cd \(dqit* at isa? port 0x4e\(dq
245.Ed
246.Pp
247Manuals not in these sections generally don't need a
248.Em SYNOPSIS .
249.Pp
250Some macros are displayed differently in the
251.Em SYNOPSIS
252section, particularly
253.Ic \&Nm ,
254.Ic \&Cd ,
255.Ic \&Fd ,
256.Ic \&Fn ,
257.Ic \&Fo ,
258.Ic \&In ,
259.Ic \&Vt ,
260and
261.Ic \&Ft .
262All of these macros are output on their own line.
263If two such dissimilar macros are pairwise invoked (except for
264.Ic \&Ft
265before
266.Ic \&Fo
267or
268.Ic \&Fn ) ,
269they are separated by a vertical space, unless in the case of
270.Ic \&Fo ,
271.Ic \&Fn ,
272and
273.Ic \&Ft ,
274which are always separated by vertical space.
275.Pp
276When text and macros following an
277.Ic \&Nm
278macro starting an input line span multiple output lines,
279all output lines but the first will be indented to align
280with the text immediately following the
281.Ic \&Nm
282macro, up to the next
283.Ic \&Nm ,
284.Ic \&Sh ,
285or
286.Ic \&Ss
287macro or the end of an enclosing block, whichever comes first.
288.It Em DESCRIPTION
289This begins with an expansion of the brief, one line description in
290.Em NAME :
291.Bd -literal -offset indent
292The
293\&.Nm
294utility does this, that, and the other.
295.Ed
296.Pp
297It usually follows with a breakdown of the options (if documenting a
298command), such as:
299.Bd -literal -offset indent
300The options are as follows:
301\&.Bl \-tag \-width Ds
302\&.It Fl v
303Print verbose information.
304\&.El
305.Ed
306.Pp
307List the options in alphabetical order,
308uppercase before lowercase for each letter and
309with no regard to whether an option takes an argument.
310Put digits in ascending order before all letter options.
311.Pp
312Manuals not documenting a command won't include the above fragment.
313.Pp
314Since the
315.Em DESCRIPTION
316section usually contains most of the text of a manual, longer manuals
317often use the
318.Ic \&Ss
319macro to form subsections.
320In very long manuals, the
321.Em DESCRIPTION
322may be split into multiple sections, each started by an
323.Ic \&Sh
324macro followed by a non-standard section name, and each having
325several subsections, like in the present
326.Nm
327manual.
328.It Em CONTEXT
329This section lists the contexts in which functions can be called in section 9.
330The contexts are autoconf, process, or interrupt.
331.It Em IMPLEMENTATION NOTES
332Implementation-specific notes should be kept here.
333This is useful when implementing standard functions that may have side
334effects or notable algorithmic implications.
335.It Em RETURN VALUES
336This section documents the
337return values of functions in sections 2, 3, and 9.
338.Pp
339See
340.Ic \&Rv .
341.It Em ENVIRONMENT
342Lists the environment variables used by the utility,
343and explains the syntax and semantics of their values.
344The
345.Xr environ 7
346manual provides examples of typical content and formatting.
347.Pp
348See
349.Ic \&Ev .
350.It Em FILES
351Documents files used.
352It's helpful to document both the file name and a short description of how
353the file is used (created, modified, etc.).
354.Pp
355See
356.Ic \&Pa .
357.It Em EXIT STATUS
358This section documents the
359command exit status for section 1, 6, and 8 utilities.
360Historically, this information was described in
361.Em DIAGNOSTICS ,
362a practise that is now discouraged.
363.Pp
364See
365.Ic \&Ex .
366.It Em EXAMPLES
367Example usages.
368This often contains snippets of well-formed, well-tested invocations.
369Make sure that examples work properly!
370.It Em DIAGNOSTICS
371Documents error messages.
372In section 4 and 9 manuals, these are usually messages printed by the
373kernel to the console and to the kernel log.
374In section 1, 6, 7, and 8, these are usually messages printed by
375userland programs to the standard error output.
376.Pp
377Historically, this section was used in place of
378.Em EXIT STATUS
379for manuals in sections 1, 6, and 8; however, this practise is
380discouraged.
381.Pp
382See
383.Ic \&Bl
384.Fl diag .
385.It Em ERRORS
386Documents
387.Xr errno 2
388settings in sections 2, 3, 4, and 9.
389.Pp
390See
391.Ic \&Er .
392.It Em SEE ALSO
393References other manuals with related topics.
394This section should exist for most manuals.
395Cross-references should conventionally be ordered first by section, then
396alphabetically (ignoring case).
397.Pp
398References to other documentation concerning the topic of the manual page,
399for example authoritative books or journal articles, may also be
400provided in this section.
401.Pp
402See
403.Ic \&Rs
404and
405.Ic \&Xr .
406.It Em STANDARDS
407References any standards implemented or used.
408If not adhering to any standards, the
409.Em HISTORY
410section should be used instead.
411.Pp
412See
413.Ic \&St .
414.It Em HISTORY
415A brief history of the subject, including where it was first implemented,
416and when it was ported to or reimplemented for the operating system at hand.
417.It Em AUTHORS
418Credits to the person or persons who wrote the code and/or documentation.
419Authors should generally be noted by both name and email address.
420.Pp
421See
422.Ic \&An .
423.It Em CAVEATS
424Common misuses and misunderstandings should be explained
425in this section.
426.It Em BUGS
427Known bugs, limitations, and work-arounds should be described
428in this section.
429.It Em SECURITY CONSIDERATIONS
430Documents any security precautions that operators should consider.
431.El
432.Sh MACRO OVERVIEW
433This overview is sorted such that macros of similar purpose are listed
434together, to help find the best macro for any given purpose.
435Deprecated macros are not included in the overview, but can be found below
436in the alphabetical
437.Sx MACRO REFERENCE .
438.Ss Document preamble and NAME section macros
439.Bl -column "Brq, Bro, Brc" description
440.It Ic \&Dd Ta document date: Cm $\&Mdocdate$ | Ar month day , year
441.It Ic \&Dt Ta document title: Ar TITLE section Op Ar arch
442.It Ic \&Os Ta operating system version: Op Ar system Op Ar version
443.It Ic \&Nm Ta document name (one argument)
444.It Ic \&Nd Ta document description (one line)
445.El
446.Ss Sections and cross references
447.Bl -column "Brq, Bro, Brc" description
448.It Ic \&Sh Ta section header (one line)
449.It Ic \&Ss Ta subsection header (one line)
450.It Ic \&Sx Ta internal cross reference to a section or subsection
451.It Ic \&Xr Ta cross reference to another manual page: Ar name section
452.It Ic \&Tg Ta tag the definition of a Ar term Pq <= 1 arguments
453.It Ic \&Pp Ta start a text paragraph (no arguments)
454.El
455.Ss Displays and lists
456.Bl -column "Brq, Bro, Brc" description
457.It Ic \&Bd , \&Ed Ta display block:
458.Fl Ar type
459.Op Fl offset Ar width
460.Op Fl compact
461.It Ic \&D1 Ta indented display (one line)
462.It Ic \&Dl Ta indented literal display (one line)
463.It Ic \&Ql Ta in-line literal display: Ql text
464.It Ic \&Bl , \&El Ta list block:
465.Fl Ar type
466.Op Fl width Ar val
467.Op Fl offset Ar val
468.Op Fl compact
469.It Ic \&It Ta list item (syntax depends on Fl Ar type )
470.It Ic \&Ta Ta table cell separator in Ic \&Bl Fl column No lists
471.It Ic \&Rs , \&%* , \&Re Ta bibliographic block (references)
472.El
473.Ss Spacing control
474.Bl -column "Brq, Bro, Brc" description
475.It Ic \&Pf Ta prefix, no following horizontal space (one argument)
476.It Ic \&Ns Ta roman font, no preceding horizontal space (no arguments)
477.It Ic \&Ap Ta apostrophe without surrounding whitespace (no arguments)
478.It Ic \&Sm Ta switch horizontal spacing mode: Op Cm on | off
479.It Ic \&Bk , \&Ek Ta keep block: Fl words
480.El
481.Ss Semantic markup for command line utilities
482.Bl -column "Brq, Bro, Brc" description
483.It Ic \&Nm Ta start a SYNOPSIS block with the name of a utility
484.It Ic \&Fl Ta command line options (flags) (>=0 arguments)
485.It Ic \&Cm Ta command modifier (>0 arguments)
486.It Ic \&Ar Ta command arguments (>=0 arguments)
487.It Ic \&Op , \&Oo , \&Oc Ta optional syntax elements (enclosure)
488.It Ic \&Ic Ta internal or interactive command (>0 arguments)
489.It Ic \&Ev Ta environmental variable (>0 arguments)
490.It Ic \&Pa Ta file system path (>=0 arguments)
491.El
492.Ss Semantic markup for function libraries
493.Bl -column "Brq, Bro, Brc" description
494.It Ic \&Lb Ta function library (one argument)
495.It Ic \&In Ta include file (one argument)
496.It Ic \&Fd Ta other preprocessor directive (>0 arguments)
497.It Ic \&Ft Ta function type (>0 arguments)
498.It Ic \&Fo , \&Fc Ta function block: Ar funcname
499.It Ic \&Fn Ta function name: Ar funcname Op Ar argument ...
500.It Ic \&Fa Ta function argument (>0 arguments)
501.It Ic \&Vt Ta variable type (>0 arguments)
502.It Ic \&Va Ta variable name (>0 arguments)
503.It Ic \&Dv Ta defined variable or preprocessor constant (>0 arguments)
504.It Ic \&Er Ta error constant (>0 arguments)
505.It Ic \&Ev Ta environmental variable (>0 arguments)
506.El
507.Ss Various semantic markup
508.Bl -column "Brq, Bro, Brc" description
509.It Ic \&An Ta author name (>0 arguments)
510.It Ic \&Lk Ta hyperlink: Ar uri Op Ar display_name
511.It Ic \&Mt Ta Do mailto Dc hyperlink: Ar localpart Ns @ Ns Ar domain
512.It Ic \&Cd Ta kernel configuration declaration (>0 arguments)
513.It Ic \&Ad Ta memory address (>0 arguments)
514.It Ic \&Ms Ta mathematical symbol (>0 arguments)
515.El
516.Ss Physical markup
517.Bl -column "Brq, Bro, Brc" description
518.It Ic \&Em Ta italic font or underline (emphasis) (>0 arguments)
519.It Ic \&Sy Ta boldface font (symbolic) (>0 arguments)
520.It Ic \&No Ta return to roman font (normal) (>0 arguments)
521.It Ic \&Bf , \&Ef Ta font block: Fl Ar type | Cm \&Em | \&Li | \&Sy
522.El
523.Ss Physical enclosures
524.Bl -column "Brq, Bro, Brc" description
525.It Ic \&Dq , \&Do , \&Dc Ta enclose in typographic double quotes: Dq text
526.It Ic \&Qq , \&Qo , \&Qc Ta enclose in typewriter double quotes: Qq text
527.It Ic \&Sq , \&So , \&Sc Ta enclose in single quotes: Sq text
528.It Ic \&Pq , \&Po , \&Pc Ta enclose in parentheses: Pq text
529.It Ic \&Bq , \&Bo , \&Bc Ta enclose in square brackets: Bq text
530.It Ic \&Brq , \&Bro , \&Brc Ta enclose in curly braces: Brq text
531.It Ic \&Aq , \&Ao , \&Ac Ta enclose in angle brackets: Aq text
532.It Ic \&Eo , \&Ec Ta generic enclosure
533.El
534.Ss Text production
535.Bl -column "Brq, Bro, Brc" description
536.It Ic \&Ex Fl std Ta standard command exit values: Op Ar utility ...
537.It Ic \&Rv Fl std Ta standard function return values: Op Ar function ...
538.It Ic \&St Ta reference to a standards document (one argument)
539.It Ic \&At Ta At
540.It Ic \&Bx Ta Bx
541.It Ic \&Bsx Ta Bsx
542.It Ic \&Nx Ta Nx
543.It Ic \&Fx Ta Fx
544.It Ic \&Ox Ta Ox
545.It Ic \&Dx Ta Dx
546.El
547.Sh MACRO REFERENCE
548This section is a canonical reference of all macros, arranged
549alphabetically.
550For the scoping of individual macros, see
551.Sx MACRO SYNTAX .
552.Bl -tag -width 3n
553.It Ic \&%A Ar first_name ... last_name
554Author name of an
555.Ic \&Rs
556block.
557Multiple authors should each be accorded their own
558.Ic \%%A
559line.
560Author names should be ordered with full or abbreviated forename(s)
561first, then full surname.
562.It Ic \&%B Ar title
563Book title of an
564.Ic \&Rs
565block.
566This macro may also be used in a non-bibliographic context when
567referring to book titles.
568.It Ic \&%C Ar location
569Publication city or location of an
570.Ic \&Rs
571block.
572.It Ic \&%D Oo Ar month day , Oc Ar year
573Publication date of an
574.Ic \&Rs
575block.
576Provide the full English name of the
577.Ar month
578and all four digits of the
579.Ar year .
580.It Ic \&%I Ar name
581Publisher or issuer name of an
582.Ic \&Rs
583block.
584.It Ic \&%J Ar name
585Journal name of an
586.Ic \&Rs
587block.
588.It Ic \&%N Ar number
589Issue number (usually for journals) of an
590.Ic \&Rs
591block.
592.It Ic \&%O Ar line
593Optional information of an
594.Ic \&Rs
595block.
596.It Ic \&%P Ar number
597Book or journal page number of an
598.Ic \&Rs
599block.
600Conventionally, the argument starts with
601.Ql p.\&
602for a single page or
603.Ql pp.\&
604for a range of pages, for example:
605.Pp
606.Dl .%P pp. 42\e(en47
607.It Ic \&%Q Ar name
608Institutional author (school, government, etc.) of an
609.Ic \&Rs
610block.
611Multiple institutional authors should each be accorded their own
612.Ic \&%Q
613line.
614.It Ic \&%R Ar name
615Technical report name of an
616.Ic \&Rs
617block.
618.It Ic \&%T Ar title
619Article title of an
620.Ic \&Rs
621block.
622This macro may also be used in a non-bibliographical context when
623referring to article titles.
624.It Ic \&%U Ar protocol Ns :// Ns Ar path
625URI of reference document.
626.It Ic \&%V Ar number
627Volume number of an
628.Ic \&Rs
629block.
630.It Ic \&Ac
631Close an
632.Ic \&Ao
633block.
634Does not have any tail arguments.
635.Tg Ad
636.It Ic \&Ad Ar address
637Memory address.
638Do not use this for postal addresses.
639.Pp
640Examples:
641.Dl \&.Ad [0,$]
642.Dl \&.Ad 0x00000000
643.Tg An
644.It Ic \&An Fl split | nosplit | Ar first_name ... last_name
645Author name.
646Can be used both for the authors of the program, function, or driver
647documented in the manual, or for the authors of the manual itself.
648Requires either the name of an author or one of the following arguments:
649.Pp
650.Bl -tag -width "-nosplitX" -offset indent -compact
651.It Fl split
652Start a new output line before each subsequent invocation of
653.Ic \&An .
654.It Fl nosplit
655The opposite of
656.Fl split .
657.El
658.Pp
659The default is
660.Fl nosplit .
661The effect of selecting either of the
662.Fl split
663modes ends at the beginning of the
664.Em AUTHORS
665section.
666In the
667.Em AUTHORS
668section, the default is
669.Fl nosplit
670for the first author listing and
671.Fl split
672for all other author listings.
673.Pp
674Examples:
675.Dl \&.An -nosplit
676.Dl \&.An Kristaps Dzonsons \&Aq \&Mt kristaps@bsd.lv
677.It Ic \&Ao Ar block
678Begin a block enclosed by angle brackets.
679Does not have any head arguments.
680This macro is almost never useful.
681See
682.Ic \&Aq
683for more details.
684.Tg Ap
685.It Ic \&Ap
686Inserts an apostrophe without any surrounding whitespace.
687This is generally used as a grammatical device when referring to the verb
688form of a function.
689.Pp
690Examples:
691.Dl \&.Fn execve \&Ap d
692.Tg Aq
693.It Ic \&Aq Ar line
694Enclose the rest of the input line in angle brackets.
695The only important use case is for email addresses.
696See
697.Ic \&Mt
698for an example.
699.Pp
700Occasionally, it is used for names of characters and keys, for example:
701.Bd -literal -offset indent
702Press the
703\&.Aq escape
704key to ...
705.Ed
706.Pp
707For URIs, use
708.Ic \&Lk
709instead, and
710.Ic \&In
711for
712.Dq #include
713directives.
714Never wrap
715.Ic \&Ar
716in
717.Ic \&Aq .
718.Pp
719Since
720.Ic \&Aq
721usually renders with non-ASCII characters in non-ASCII output modes,
722do not use it where the ASCII characters
723.Sq <
724and
725.Sq >
726are required as syntax elements.
727Instead, use these characters directly in such cases, combining them
728with the macros
729.Ic \&Pf ,
730.Ic \&Ns ,
731or
732.Ic \&Eo
733as needed.
734.Pp
735See also
736.Ic \&Ao .
737.Tg Ar
738.It Ic \&Ar Op Ar placeholder ...
739Command arguments.
740If an argument is not provided, the string
741.Dq file ...\&
742is used as a default.
743.Pp
744Examples:
745.Dl ".Fl o Ar file"
746.Dl ".Ar"
747.Dl ".Ar arg1 , arg2 ."
748.Pp
749The arguments to the
750.Ic \&Ar
751macro are names and placeholders for command arguments;
752for fixed strings to be passed verbatim as arguments, use
753.Ic \&Fl
754or
755.Ic \&Cm .
756.Tg At
757.It Ic \&At Op Ar version
758Formats an
759.At
760version.
761Accepts one optional argument:
762.Pp
763.Bl -tag -width "v[1-7] | 32vX" -offset indent -compact
764.It Cm v[1-7] | 32v
765A version of
766.At .
767.It Cm III
768.At III .
769.It Cm V | V.[1-4]
770A version of
771.At V .
772.El
773.Pp
774Note that these arguments do not begin with a hyphen.
775.Pp
776Examples:
777.Dl \&.At
778.Dl \&.At III
779.Dl \&.At V.1
780.Pp
781See also
782.Ic \&Bsx ,
783.Ic \&Bx ,
784.Ic \&Dx ,
785.Ic \&Fx ,
786.Ic \&Nx ,
787and
788.Ic \&Ox .
789.It Ic \&Bc
790Close a
791.Ic \&Bo
792block.
793Does not have any tail arguments.
794.Tg Bd
795.It Ic \&Bd Fl Ns Ar type Oo Fl offset Ar width Oc Op Fl compact
796Begin a display block.
797Display blocks are used to select a different indentation and
798justification than the one used by the surrounding text.
799They may contain both macro lines and text lines.
800By default, a display block is preceded by a vertical space.
801.Pp
802The
803.Ar type
804must be one of the following:
805.Bl -tag -width 13n -offset indent
806.It Fl centered
807Produce one output line from each input line, and center-justify each line.
808Using this display type is not recommended; many
809.Nm
810implementations render it poorly.
811.It Fl filled
812Change the positions of line breaks to fill each line, and left- and
813right-justify the resulting block.
814.It Fl literal
815Produce one output line from each input line,
816and do not justify the block at all.
817Preserve white space as it appears in the input.
818Always use a constant-width font.
819Use this for displaying source code.
820.It Fl ragged
821Change the positions of line breaks to fill each line, and left-justify
822the resulting block.
823.It Fl unfilled
824The same as
825.Fl literal ,
826but using the same font as for normal text, which is a variable width font
827if supported by the output device.
828.El
829.Pp
830The
831.Ar type
832must be provided first.
833Additional arguments may follow:
834.Bl -tag -width 13n -offset indent
835.It Fl offset Ar width
836Indent the display by the
837.Ar width ,
838which may be one of the following:
839.Bl -item
840.It
841One of the pre-defined strings
842.Cm indent ,
843the width of a standard indentation (six constant width characters);
844.Cm indent-two ,
845twice
846.Cm indent ;
847.Cm left ,
848which has no effect;
849.Cm right ,
850which justifies to the right margin; or
851.Cm center ,
852which aligns around an imagined center axis.
853.It
854A macro invocation, which selects a predefined width
855associated with that macro.
856The most popular is the imaginary macro
857.Ar \&Ds ,
858which resolves to
859.Sy 6n .
860.It
861A scaling width as described in
862.Xr roff 7 .
863.It
864An arbitrary string, which indents by the length of this string.
865.El
866.Pp
867When the argument is missing,
868.Fl offset
869is ignored.
870.It Fl compact
871Do not assert vertical space before the display.
872.El
873.Pp
874Examples:
875.Bd -literal -offset indent
876\&.Bd \-literal \-offset indent \-compact
877   Hello       world.
878\&.Ed
879.Ed
880.Pp
881See also
882.Ic \&D1
883and
884.Ic \&Dl .
885.Tg Bf
886.It Ic \&Bf Fl emphasis | literal | symbolic | Cm \&Em | \&Li | \&Sy
887Change the font mode for a scoped block of text.
888The
889.Fl emphasis
890and
891.Cm \&Em
892argument are equivalent, as are
893.Fl symbolic
894and
895.Cm \&Sy ,
896and
897.Fl literal
898and
899.Cm \&Li .
900Without an argument, this macro does nothing.
901The font mode continues until broken by a new font mode in a nested
902scope or
903.Ic \&Ef
904is encountered.
905.Pp
906See also
907.Ic \&Li ,
908.Ic \&Ef ,
909.Ic \&Em ,
910and
911.Ic \&Sy .
912.Tg Bk
913.It Ic \&Bk Fl words
914For each macro, keep its output together on the same output line,
915until the end of the macro or the end of the input line is reached,
916whichever comes first.
917Line breaks in text lines are unaffected.
918.Pp
919The
920.Fl words
921argument is required; additional arguments are ignored.
922.Pp
923The following example will not break within each
924.Ic \&Op
925macro line:
926.Bd -literal -offset indent
927\&.Bk \-words
928\&.Op Fl f Ar flags
929\&.Op Fl o Ar output
930\&.Ek
931.Ed
932.Pp
933Be careful in using over-long lines within a keep block!
934Doing so will clobber the right margin.
935.Tg Bl
936.It Xo
937.Ic \&Bl
938.Fl Ns Ar type
939.Op Fl width Ar val
940.Op Fl offset Ar val
941.Op Fl compact
942.Op Ar col ...
943.Xc
944Begin a list.
945Lists consist of items specified using the
946.Ic \&It
947macro, containing a head or a body or both.
948.Pp
949The list
950.Ar type
951is mandatory and must be specified first.
952The
953.Fl width
954and
955.Fl offset
956arguments accept macro names as described for
957.Ic \&Bd
958.Fl offset ,
959scaling widths as described in
960.Xr roff 7 ,
961or use the length of the given string.
962The
963.Fl offset
964is a global indentation for the whole list, affecting both item heads
965and bodies.
966For those list types supporting it, the
967.Fl width
968argument requests an additional indentation of item bodies,
969to be added to the
970.Fl offset .
971Unless the
972.Fl compact
973argument is specified, list entries are separated by vertical space.
974.Pp
975A list must specify one of the following list types:
976.Bl -tag -width 12n -offset indent
977.It Fl bullet
978No item heads can be specified, but a bullet will be printed at the head
979of each item.
980Item bodies start on the same output line as the bullet
981and are indented according to the
982.Fl width
983argument.
984.It Fl column
985A columnated list.
986The
987.Fl width
988argument has no effect; instead, the string length of each argument
989specifies the width of one column.
990If the first line of the body of a
991.Fl column
992list is not an
993.Ic \&It
994macro line,
995.Ic \&It
996contexts spanning one input line each are implied until an
997.Ic \&It
998macro line is encountered, at which point items start being interpreted as
999described in the
1000.Ic \&It
1001documentation.
1002.It Fl dash
1003Like
1004.Fl bullet ,
1005except that dashes are used in place of bullets.
1006.It Fl diag
1007Like
1008.Fl inset ,
1009except that item heads are not parsed for macro invocations.
1010Most often used in the
1011.Em DIAGNOSTICS
1012section with error constants in the item heads.
1013.It Fl enum
1014A numbered list.
1015No item heads can be specified.
1016Formatted like
1017.Fl bullet ,
1018except that cardinal numbers are used in place of bullets,
1019starting at 1.
1020.It Fl hang
1021Like
1022.Fl tag ,
1023except that the first lines of item bodies are not indented, but follow
1024the item heads like in
1025.Fl inset
1026lists.
1027.It Fl hyphen
1028Synonym for
1029.Fl dash .
1030.It Fl inset
1031Item bodies follow items heads on the same line, using normal inter-word
1032spacing.
1033Bodies are not indented, and the
1034.Fl width
1035argument is ignored.
1036.It Fl item
1037No item heads can be specified, and none are printed.
1038Bodies are not indented, and the
1039.Fl width
1040argument is ignored.
1041.It Fl ohang
1042Item bodies start on the line following item heads and are not indented.
1043The
1044.Fl width
1045argument is ignored.
1046.It Fl tag
1047Item bodies are indented according to the
1048.Fl width
1049argument.
1050When an item head fits inside the indentation, the item body follows
1051this head on the same output line.
1052Otherwise, the body starts on the output line following the head.
1053.El
1054.Pp
1055Lists may be nested within lists and displays.
1056Nesting of
1057.Fl column
1058and
1059.Fl enum
1060lists may not be portable.
1061.Pp
1062See also
1063.Ic \&El
1064and
1065.Ic \&It .
1066.It Ic \&Bo Ar block
1067Begin a block enclosed by square brackets.
1068Does not have any head arguments.
1069.Pp
1070Examples:
1071.Bd -literal -offset indent -compact
1072\&.Bo 1 ,
1073\&.Dv BUFSIZ \&Bc
1074.Ed
1075.Pp
1076See also
1077.Ic \&Bq .
1078.Tg Bq
1079.It Ic \&Bq Ar line
1080Encloses its arguments in square brackets.
1081.Pp
1082Examples:
1083.Dl \&.Bq 1 , \&Dv BUFSIZ
1084.Pp
1085.Em Remarks :
1086this macro is sometimes abused to emulate optional arguments for
1087commands; the correct macros to use for this purpose are
1088.Ic \&Op ,
1089.Ic \&Oo ,
1090and
1091.Ic \&Oc .
1092.Pp
1093See also
1094.Ic \&Bo .
1095.It Ic \&Brc
1096Close a
1097.Ic \&Bro
1098block.
1099Does not have any tail arguments.
1100.It Ic \&Bro Ar block
1101Begin a block enclosed by curly braces.
1102Does not have any head arguments.
1103.Pp
1104Examples:
1105.Bd -literal -offset indent -compact
1106\&.Bro 1 , ... ,
1107\&.Va n \&Brc
1108.Ed
1109.Pp
1110See also
1111.Ic \&Brq .
1112.Tg Brq
1113.It Ic \&Brq Ar line
1114Encloses its arguments in curly braces.
1115.Pp
1116Examples:
1117.Dl \&.Brq 1 , ... , \&Va n
1118.Pp
1119See also
1120.Ic \&Bro .
1121.Tg Bsx
1122.It Ic \&Bsx Op Ar version
1123Format the
1124.Bsx
1125version provided as an argument, or a default value if
1126no argument is provided.
1127.Pp
1128Examples:
1129.Dl \&.Bsx 1.0
1130.Dl \&.Bsx
1131.Pp
1132See also
1133.Ic \&At ,
1134.Ic \&Bx ,
1135.Ic \&Dx ,
1136.Ic \&Fx ,
1137.Ic \&Nx ,
1138and
1139.Ic \&Ox .
1140.It Ic \&Bt
1141Supported only for compatibility, do not use this in new manuals.
1142Prints
1143.Dq is currently in beta test.
1144.Tg Bx
1145.It Ic \&Bx Op Ar version Op Ar variant
1146Format the
1147.Bx
1148version provided as an argument, or a default value if no
1149argument is provided.
1150.Pp
1151Examples:
1152.Dl \&.Bx 4.3 Tahoe
1153.Dl \&.Bx 4.4
1154.Dl \&.Bx
1155.Pp
1156See also
1157.Ic \&At ,
1158.Ic \&Bsx ,
1159.Ic \&Dx ,
1160.Ic \&Fx ,
1161.Ic \&Nx ,
1162and
1163.Ic \&Ox .
1164.Tg Cd
1165.It Ic \&Cd Ar line
1166Kernel configuration declaration.
1167This denotes strings accepted by
1168.Xr config 8 .
1169It is most often used in section 4 manual pages.
1170.Pp
1171Examples:
1172.Dl \&.Cd device le0 at scode?
1173.Pp
1174.Em Remarks :
1175this macro is commonly abused by using quoted literals to retain
1176whitespace and align consecutive
1177.Ic \&Cd
1178declarations.
1179This practise is discouraged.
1180.Tg Cm
1181.It Ic \&Cm Ar keyword ...
1182Command modifiers.
1183Typically used for fixed strings passed as arguments to interactive
1184commands, to commands in interpreted scripts, or to configuration
1185file directives, unless
1186.Ic \&Fl
1187is more appropriate.
1188.Pp
1189Examples:
1190.Dl ".Nm mt Fl f Ar device Cm rewind"
1191.Dl ".Nm ps Fl o Cm pid , Ns Cm command"
1192.Dl ".Nm dd Cm if= Ns Ar file1 Cm of= Ns Ar file2"
1193.Dl ".Ic set Fl o Cm vi"
1194.Dl ".Ic lookup Cm file bind"
1195.Dl ".Ic permit Ar identity Op Cm as Ar target"
1196.Tg D1
1197.It Ic \&D1 Ar line
1198One-line indented display.
1199This is formatted by the default rules and is useful for simple indented
1200statements.
1201It is followed by a newline.
1202.Pp
1203Examples:
1204.Dl \&.D1 \&Fl abcdefgh
1205.Pp
1206See also
1207.Ic \&Bd
1208and
1209.Ic \&Dl .
1210.It Ic \&Db
1211This macro is obsolete.
1212No replacement is needed.
1213It is ignored by
1214.Xr mandoc 1
1215and groff including its arguments.
1216It was formerly used to toggle a debugging mode.
1217.It Ic \&Dc
1218Close a
1219.Ic \&Do
1220block.
1221Does not have any tail arguments.
1222.Tg Dd
1223.It Ic \&Dd Cm $\&Mdocdate$ | Ar month day , year
1224Document date for display in the page footer,
1225by convention the date of the last change.
1226This is the mandatory first macro of any
1227.Nm
1228manual.
1229.Pp
1230The
1231.Ar month
1232is the full English month name, the
1233.Ar day
1234is an integer number, and the
1235.Ar year
1236is the full four-digit year.
1237.Pp
1238Other arguments are not portable; the
1239.Xr mandoc 1
1240utility handles them as follows:
1241.Bl -dash -offset 3n -compact
1242.It
1243To have the date automatically filled in by the
1244.Ox
1245version of
1246.Xr cvs 1 ,
1247the special string
1248.Dq $\&Mdocdate$
1249can be given as an argument.
1250.It
1251The traditional, purely numeric
1252.Xr man 7
1253format
1254.Ar year Ns \(en Ns Ar month Ns \(en Ns Ar day
1255is accepted, too.
1256.It
1257If a date string cannot be parsed, it is used verbatim.
1258.It
1259If no date string is given, the current date is used.
1260.El
1261.Pp
1262Examples:
1263.Dl \&.Dd $\&Mdocdate$
1264.Dl \&.Dd $\&Mdocdate: July 2 2018$
1265.Dl \&.Dd July 2, 2018
1266.Pp
1267See also
1268.Ic \&Dt
1269and
1270.Ic \&Os .
1271.Tg Dl
1272.It Ic \&Dl Ar line
1273One-line indented display.
1274This is formatted as literal text and is useful for commands and
1275invocations.
1276It is followed by a newline.
1277.Pp
1278Examples:
1279.Dl \&.Dl % mandoc mdoc.7 \e(ba less
1280.Pp
1281See also
1282.Ic \&Ql ,
1283.Ic \&Bd Fl literal ,
1284and
1285.Ic \&D1 .
1286.It Ic \&Do Ar block
1287Begin a block enclosed by double quotes.
1288Does not have any head arguments.
1289.Pp
1290Examples:
1291.Bd -literal -offset indent -compact
1292\&.Do
1293April is the cruellest month
1294\&.Dc
1295\e(em T.S. Eliot
1296.Ed
1297.Pp
1298See also
1299.Ic \&Dq .
1300.Tg Dq
1301.It Ic \&Dq Ar line
1302Encloses its arguments in
1303.Dq typographic
1304double-quotes.
1305.Pp
1306Examples:
1307.Bd -literal -offset indent -compact
1308\&.Dq April is the cruellest month
1309\e(em T.S. Eliot
1310.Ed
1311.Pp
1312See also
1313.Ic \&Qq ,
1314.Ic \&Sq ,
1315and
1316.Ic \&Do .
1317.Tg Dt
1318.It Ic \&Dt Ar TITLE section Op Ar arch
1319Document title for display in the page header.
1320This is the mandatory second macro of any
1321.Nm
1322file.
1323.Pp
1324Its arguments are as follows:
1325.Bl -tag -width section -offset 2n
1326.It Ar TITLE
1327The document's title (name), defaulting to
1328.Dq UNTITLED
1329if unspecified.
1330To achieve a uniform appearance of page header lines,
1331it should by convention be all caps.
1332.It Ar section
1333The manual section.
1334This may be one of
1335.Cm 1
1336.Pq General Commands ,
1337.Cm 2
1338.Pq System Calls ,
1339.Cm 3
1340.Pq Library Functions ,
1341.Cm 3p
1342.Pq Perl Library ,
1343.Cm 4
1344.Pq Device Drivers ,
1345.Cm 5
1346.Pq File Formats ,
1347.Cm 6
1348.Pq Games ,
1349.Cm 7
1350.Pq Miscellaneous Information ,
1351.Cm 8
1352.Pq System Manager's Manual ,
1353or
1354.Cm 9
1355.Pq Kernel Developer's Manual .
1356It should correspond to the manual's filename suffix and defaults to
1357the empty string if unspecified.
1358.It Ar arch
1359This specifies the machine architecture a manual page applies to,
1360where relevant.
1361For
1362.Ox ,
1363the following are valid architectures:
1364.Cm alpha ,
1365.Cm amd64 ,
1366.Cm armv7 ,
1367.Cm arm64 ,
1368.Cm hppa ,
1369.Cm i386 ,
1370.Cm landisk ,
1371.Cm loongson ,
1372.Cm luna88k ,
1373.Cm macppc ,
1374.Cm mips64 ,
1375.Cm octeon ,
1376.Cm powerpc64 ,
1377.Cm riscv64 ,
1378and
1379.Cm sparc64 .
1380.El
1381.Pp
1382Examples:
1383.Dl \&.Dt FOO 1
1384.Dl \&.Dt FOO 9 i386
1385.Pp
1386See also
1387.Ic \&Dd
1388and
1389.Ic \&Os .
1390.Tg Dv
1391.It Ic \&Dv Ar identifier ...
1392Defined variables such as preprocessor constants, constant symbols,
1393enumeration values, and so on.
1394.Pp
1395Examples:
1396.Dl \&.Dv NULL
1397.Dl \&.Dv BUFSIZ
1398.Dl \&.Dv STDOUT_FILENO
1399.Pp
1400See also
1401.Ic \&Er
1402and
1403.Ic \&Ev
1404for special-purpose constants,
1405.Ic \&Va
1406for variable symbols, and
1407.Ic \&Fd
1408for listing preprocessor variable definitions in the
1409.Em SYNOPSIS .
1410.Tg Dx
1411.It Ic \&Dx Op Ar version
1412Format the
1413.Dx
1414version provided as an argument, or a default
1415value if no argument is provided.
1416.Pp
1417Examples:
1418.Dl \&.Dx 2.4.1
1419.Dl \&.Dx
1420.Pp
1421See also
1422.Ic \&At ,
1423.Ic \&Bsx ,
1424.Ic \&Bx ,
1425.Ic \&Fx ,
1426.Ic \&Nx ,
1427and
1428.Ic \&Ox .
1429.It Ic \&Ec Op Ar closing_delimiter
1430Close a scope started by
1431.Ic \&Eo .
1432.Pp
1433The
1434.Ar closing_delimiter
1435argument is used as the enclosure tail, for example, specifying \e(rq
1436will emulate
1437.Ic \&Dc .
1438.It Ic \&Ed
1439End a display context started by
1440.Ic \&Bd .
1441.It Ic \&Ef
1442End a font mode context started by
1443.Ic \&Bf .
1444.It Ic \&Ek
1445End a keep context started by
1446.Ic \&Bk .
1447.It Ic \&El
1448End a list context started by
1449.Ic \&Bl .
1450See also
1451.Ic \&It .
1452.Tg Em
1453.It Ic \&Em Ar word ...
1454Request an italic font.
1455If the output device does not provide that, underline.
1456.Pp
1457This is most often used for stress emphasis (not to be confused with
1458importance, see
1459.Ic \&Sy ) .
1460In the rare cases where none of the semantic markup macros fit,
1461it can also be used for technical terms and placeholders, except
1462that for syntax elements,
1463.Ic \&Sy
1464and
1465.Ic \&Ar
1466are preferred, respectively.
1467.Pp
1468Examples:
1469.Bd -literal -compact -offset indent
1470Selected lines are those
1471\&.Em not
1472matching any of the specified patterns.
1473Some of the functions use a
1474\&.Em hold space
1475to save the pattern space for subsequent retrieval.
1476.Ed
1477.Pp
1478See also
1479.Ic \&No ,
1480.Ic \&Ql ,
1481and
1482.Ic \&Sy .
1483.It Ic \&En Ar word ...
1484This macro is obsolete.
1485Use
1486.Ic \&Eo
1487or any of the other enclosure macros.
1488.Pp
1489It encloses its argument in the delimiters specified by the last
1490.Ic \&Es
1491macro.
1492.Tg Eo
1493.It Ic \&Eo Op Ar opening_delimiter
1494An arbitrary enclosure.
1495The
1496.Ar opening_delimiter
1497argument is used as the enclosure head, for example, specifying \e(lq
1498will emulate
1499.Ic \&Do .
1500.Tg Er
1501.It Ic \&Er Ar identifier ...
1502Error constants for definitions of the
1503.Va errno
1504libc global variable.
1505This is most often used in section 2 and 3 manual pages.
1506.Pp
1507Examples:
1508.Dl \&.Er EPERM
1509.Dl \&.Er ENOENT
1510.Pp
1511See also
1512.Ic \&Dv
1513for general constants.
1514.It Ic \&Es Ar opening_delimiter closing_delimiter
1515This macro is obsolete.
1516Use
1517.Ic \&Eo
1518or any of the other enclosure macros.
1519.Pp
1520It takes two arguments, defining the delimiters to be used by subsequent
1521.Ic \&En
1522macros.
1523.Tg Ev
1524.It Ic \&Ev Ar identifier ...
1525Environmental variables such as those specified in
1526.Xr environ 7 .
1527.Pp
1528Examples:
1529.Dl \&.Ev DISPLAY
1530.Dl \&.Ev PATH
1531.Pp
1532See also
1533.Ic \&Dv
1534for general constants.
1535.Tg Ex
1536.It Ic \&Ex Fl std Op Ar utility ...
1537Insert a standard sentence regarding command exit values of 0 on success
1538and >0 on failure.
1539This is most often used in section 1, 6, and 8 manual pages.
1540.Pp
1541If
1542.Ar utility
1543is not specified, the document's name set by
1544.Ic \&Nm
1545is used.
1546Multiple
1547.Ar utility
1548arguments are treated as separate utilities.
1549.Pp
1550See also
1551.Ic \&Rv .
1552.Tg Fa
1553.It Ic \&Fa Ar argument ...
1554Function argument or parameter.
1555Each argument may be a name and a type (recommended for the
1556.Em SYNOPSIS
1557section), a name alone (for function invocations),
1558or a type alone (for function prototypes).
1559If both a type and a name are given or if the type consists of multiple
1560words, all words belonging to the same function argument have to be
1561given in a single argument to the
1562.Ic \&Fa
1563macro.
1564.Pp
1565This macro is also used to specify the field name of a structure.
1566.Pp
1567Most often, the
1568.Ic \&Fa
1569macro is used in the
1570.Em SYNOPSIS
1571within
1572.Ic \&Fo
1573blocks when documenting multi-line function prototypes.
1574If invoked with multiple arguments, the arguments are separated by a
1575comma.
1576Furthermore, if the following macro is another
1577.Ic \&Fa ,
1578the last argument will also have a trailing comma.
1579.Pp
1580Examples:
1581.Dl \&.Fa \(dqconst char *p\(dq
1582.Dl \&.Fa \(dqint a\(dq \(dqint b\(dq \(dqint c\(dq
1583.Dl \&.Fa \(dqchar *\(dq size_t
1584.Pp
1585See also
1586.Ic \&Fo .
1587.It Ic \&Fc
1588End a function context started by
1589.Ic \&Fo .
1590.Tg Fd
1591.It Ic \&Fd Pf # Ar directive Op Ar argument ...
1592Preprocessor directive, in particular for listing it in the
1593.Em SYNOPSIS .
1594Historically, it was also used to document include files.
1595The latter usage has been deprecated in favour of
1596.Ic \&In .
1597.Pp
1598Examples:
1599.Dl \&.Fd #define sa_handler __sigaction_u.__sa_handler
1600.Dl \&.Fd #define SIO_MAXNFDS
1601.Dl \&.Fd #ifdef FS_DEBUG
1602.Dl \&.Ft void
1603.Dl \&.Fn dbg_open \(dqconst char *\(dq
1604.Dl \&.Fd #endif
1605.Pp
1606See also
1607.Sx MANUAL STRUCTURE ,
1608.Ic \&In ,
1609and
1610.Ic \&Dv .
1611.Tg Fl
1612.It Ic \&Fl Op Ar word ...
1613Command-line flag or option.
1614Used when listing arguments to command-line utilities.
1615For each argument, prints an ASCII hyphen-minus character
1616.Sq \- ,
1617immediately followed by the argument.
1618If no arguments are provided, a hyphen-minus is printed followed by a space.
1619If the argument is a macro, a hyphen-minus is prefixed
1620to the subsequent macro output.
1621.Pp
1622Examples:
1623.Dl ".Nm du Op Fl H | L | P"
1624.Dl ".Nm ls Op Fl 1AaCcdFfgHhikLlmnopqRrSsTtux"
1625.Dl ".Nm route Cm add Fl inet Ar destination gateway"
1626.Dl ".Nm locate.updatedb Op Fl \e-fcodes Ns = Ns Ar dbfile"
1627.Dl ".Nm aucat Fl o Fl"
1628.Dl ".Nm kill Fl Ar signal_number"
1629.Pp
1630For GNU-style long options, escaping the additional hyphen-minus is not
1631strictly required, but may be safer with future versions of GNU troff; see
1632.Xr mandoc_char 7
1633for details.
1634.Pp
1635See also
1636.Ic \&Cm .
1637.Tg Fn
1638.It Ic \&Fn Ar funcname Op Ar argument ...
1639A function name.
1640.Pp
1641Function arguments are surrounded in parenthesis and
1642are delimited by commas.
1643If no arguments are specified, blank parenthesis are output.
1644In the
1645.Em SYNOPSIS
1646section, this macro starts a new output line,
1647and a blank line is automatically inserted between function definitions.
1648.Pp
1649Examples:
1650.Dl \&.Fn \(dqint funcname\(dq \(dqint arg0\(dq \(dqint arg1\(dq
1651.Dl \&.Fn funcname \(dqint arg0\(dq
1652.Dl \&.Fn funcname arg0
1653.Bd -literal -offset indent
1654\&.Ft functype
1655\&.Fn funcname
1656.Ed
1657.Pp
1658When referring to a function documented in another manual page, use
1659.Ic \&Xr
1660instead.
1661See also
1662.Sx MANUAL STRUCTURE ,
1663.Ic \&Fo ,
1664and
1665.Ic \&Ft .
1666.Tg Fo
1667.It Ic \&Fo Ar funcname
1668Begin a function block.
1669This is a multi-line version of
1670.Ic \&Fn .
1671.Pp
1672Invocations usually occur in the following context:
1673.Bd -ragged -offset indent
1674.Pf \. Ic \&Ft Ar functype
1675.br
1676.Pf \. Ic \&Fo Ar funcname
1677.br
1678.Pf \. Ic \&Fa Qq Ar argtype Ar argname
1679.br
1680\&.\.\.
1681.br
1682.Pf \. Ic \&Fc
1683.Ed
1684.Pp
1685A
1686.Ic \&Fo
1687scope is closed by
1688.Ic \&Fc .
1689.Pp
1690See also
1691.Sx MANUAL STRUCTURE ,
1692.Ic \&Fa ,
1693.Ic \&Fc ,
1694and
1695.Ic \&Ft .
1696.It Ic \&Fr Ar number
1697This macro is obsolete.
1698No replacement markup is needed.
1699.Pp
1700It was used to show numerical function return values in an italic font.
1701.Tg Ft
1702.It Ic \&Ft Ar functype
1703A function type.
1704.Pp
1705In the
1706.Em SYNOPSIS
1707section, a new output line is started after this macro.
1708.Pp
1709Examples:
1710.Dl \&.Ft int
1711.Bd -literal -offset indent -compact
1712\&.Ft functype
1713\&.Fn funcname
1714.Ed
1715.Pp
1716See also
1717.Sx MANUAL STRUCTURE ,
1718.Ic \&Fn ,
1719and
1720.Ic \&Fo .
1721.Tg Fx
1722.It Ic \&Fx Op Ar version
1723Format the
1724.Fx
1725version provided as an argument, or a default value
1726if no argument is provided.
1727.Pp
1728Examples:
1729.Dl \&.Fx 7.1
1730.Dl \&.Fx
1731.Pp
1732See also
1733.Ic \&At ,
1734.Ic \&Bsx ,
1735.Ic \&Bx ,
1736.Ic \&Dx ,
1737.Ic \&Nx ,
1738and
1739.Ic \&Ox .
1740.It Ic \&Hf Ar filename
1741This macro is not implemented in
1742.Xr mandoc 1 .
1743It was used to include the contents of a (header) file literally.
1744.Tg Ic
1745.It Ic \&Ic Ar keyword ...
1746Internal or interactive command, or configuration instruction
1747in a configuration file.
1748See also
1749.Ic \&Cm .
1750.Pp
1751Examples:
1752.Dl \&.Ic :wq
1753.Dl \&.Ic hash
1754.Dl \&.Ic alias
1755.Pp
1756Note that using
1757.Ic \&Ql ,
1758.Ic \&Dl ,
1759or
1760.Ic \&Bd Fl literal
1761is preferred for displaying code samples; the
1762.Ic \&Ic
1763macro is used when referring to an individual command name.
1764.Tg In
1765.It Ic \&In Ar filename
1766The name of an include file.
1767This macro is most often used in section 2, 3, and 9 manual pages.
1768.Pp
1769When invoked as the first macro on an input line in the
1770.Em SYNOPSIS
1771section, the argument is displayed in angle brackets
1772and preceded by
1773.Qq #include ,
1774and a blank line is inserted in front if there is a preceding
1775function declaration.
1776In other sections, it only encloses its argument in angle brackets
1777and causes no line break.
1778.Pp
1779Examples:
1780.Dl \&.In sys/types.h
1781.Pp
1782See also
1783.Sx MANUAL STRUCTURE .
1784.Tg It
1785.It Ic \&It Op Ar head
1786A list item.
1787The syntax of this macro depends on the list type.
1788.Pp
1789Lists
1790of type
1791.Fl hang ,
1792.Fl ohang ,
1793.Fl inset ,
1794and
1795.Fl diag
1796have the following syntax:
1797.Pp
1798.D1 Pf \. Ic \&It Ar args
1799.Pp
1800Lists of type
1801.Fl bullet ,
1802.Fl dash ,
1803.Fl enum ,
1804.Fl hyphen
1805and
1806.Fl item
1807have the following syntax:
1808.Pp
1809.D1 Pf \. Ic \&It
1810.Pp
1811with subsequent lines interpreted within the scope of the
1812.Ic \&It
1813until either a closing
1814.Ic \&El
1815or another
1816.Ic \&It .
1817.Pp
1818The
1819.Fl tag
1820list has the following syntax:
1821.Pp
1822.D1 Pf \. Ic \&It Op Cm args
1823.Pp
1824Subsequent lines are interpreted as with
1825.Fl bullet
1826and family.
1827The line arguments correspond to the list's left-hand side; body
1828arguments correspond to the list's contents.
1829.Pp
1830The
1831.Fl column
1832list is the most complicated.
1833Its syntax is as follows:
1834.Pp
1835.D1 Pf \. Ic \&It Ar cell Op Ic \&Ta Ar cell ...
1836.D1 Pf \. Ic \&It Ar cell Op <TAB> Ar cell ...
1837.Pp
1838The arguments consist of one or more lines of text and macros
1839representing a complete table line.
1840Cells within the line are delimited by the special
1841.Ic \&Ta
1842block macro or by literal tab characters.
1843.Pp
1844Using literal tabs is strongly discouraged because they are very
1845hard to use correctly and
1846.Nm
1847code using them is very hard to read.
1848In particular, a blank character is syntactically significant
1849before and after the literal tab character.
1850If a word precedes or follows the tab without an intervening blank,
1851that word is never interpreted as a macro call, but always output
1852literally.
1853.Pp
1854The tab cell delimiter may only be used within the
1855.Ic \&It
1856line itself; on following lines, only the
1857.Ic \&Ta
1858macro can be used to delimit cells, and portability requires that
1859.Ic \&Ta
1860is called by other macros: some parsers do not recognize it when
1861it appears as the first macro on a line.
1862.Pp
1863Note that quoted strings may span tab-delimited cells on an
1864.Ic \&It
1865line.
1866For example,
1867.Pp
1868.Dl .It \(dqcol1 ,\& <TAB> col2 ,\(dq \&;
1869.Pp
1870will preserve the whitespace before both commas,
1871but not the whitespace before the semicolon.
1872.Pp
1873See also
1874.Ic \&Bl .
1875.Tg Lb
1876.It Ic \&Lb Cm lib Ns Ar name
1877Specify a library.
1878.Pp
1879The
1880.Ar name
1881parameter may be a system library, such as
1882.Cm z
1883or
1884.Cm pam ,
1885in which case a small library description is printed next to the linker
1886invocation; or a custom library, in which case the library name is
1887printed in quotes.
1888This is most commonly used in the
1889.Em SYNOPSIS
1890section as described in
1891.Sx MANUAL STRUCTURE .
1892.Pp
1893Examples:
1894.Dl \&.Lb libz
1895.Dl \&.Lb libmandoc
1896.Tg Li
1897.It Ic \&Li Ar word ...
1898Request a typewriter (literal) font.
1899Deprecated because on terminal output devices, this is usually
1900indistinguishable from normal text.
1901For literal displays, use
1902.Ic \&Ql Pq in-line ,
1903.Ic \&Dl Pq single line ,
1904or
1905.Ic \&Bd Fl literal Pq multi-line
1906instead.
1907.Tg Lk
1908.It Ic \&Lk Ar uri Op Ar display_name
1909Format a hyperlink.
1910.Pp
1911Examples:
1912.Dl \&.Lk https://bsd.lv \(dqThe BSD.lv Project\(dq
1913.Dl \&.Lk https://bsd.lv
1914.Pp
1915See also
1916.Ic \&Mt .
1917.It Ic \&Lp
1918Deprecated synonym for
1919.Ic \&Pp .
1920.Tg Ms
1921.It Ic \&Ms Ar name
1922Display a mathematical symbol.
1923.Pp
1924Examples:
1925.Dl \&.Ms sigma
1926.Dl \&.Ms aleph
1927.Tg Mt
1928.It Ic \&Mt Ar localpart Ns @ Ns Ar domain
1929Format a
1930.Dq mailto:
1931hyperlink.
1932.Pp
1933Examples:
1934.Dl \&.Mt discuss@manpages.bsd.lv
1935.Dl \&.An Kristaps Dzonsons \&Aq \&Mt kristaps@bsd.lv
1936.Tg Nd
1937.It Ic \&Nd Ar line
1938A one line description of the manual's content.
1939This is the mandatory last macro of the
1940.Em NAME
1941section and not appropriate for other sections.
1942.Pp
1943Examples:
1944.Dl Pf . Ic \&Nd mdoc language reference
1945.Dl Pf . Ic \&Nd format and display UNIX manuals
1946.Pp
1947The
1948.Ic \&Nd
1949macro technically accepts child macros and terminates with a subsequent
1950.Ic \&Sh
1951invocation.
1952Do not assume this behaviour: some
1953.Xr whatis 1
1954database generators are not smart enough to parse more than the line
1955arguments and will display macros verbatim.
1956.Pp
1957See also
1958.Ic \&Nm .
1959.Tg Nm
1960.It Ic \&Nm Op Ar name
1961The name of the manual page, or \(em in particular in section 1, 6,
1962and 8 pages \(em of an additional command or feature documented in
1963the manual page.
1964When first invoked, the
1965.Ic \&Nm
1966macro expects a single argument, the name of the manual page.
1967Usually, the first invocation happens in the
1968.Em NAME
1969section of the page.
1970The specified name will be remembered and used whenever the macro is
1971called again without arguments later in the page.
1972The
1973.Ic \&Nm
1974macro uses
1975.Sx Block full-implicit
1976semantics when invoked as the first macro on an input line in the
1977.Em SYNOPSIS
1978section; otherwise, it uses ordinary
1979.Sx In-line
1980semantics.
1981.Pp
1982Examples:
1983.Bd -literal -offset indent
1984\&.Sh SYNOPSIS
1985\&.Nm cat
1986\&.Op Fl benstuv
1987\&.Op Ar
1988.Ed
1989.Pp
1990In the
1991.Em SYNOPSIS
1992of section 2, 3 and 9 manual pages, use the
1993.Ic \&Fn
1994macro rather than
1995.Ic \&Nm
1996to mark up the name of the manual page.
1997.Tg No
1998.It Ic \&No Ar word ...
1999Normal text.
2000Closes the scope of any preceding in-line macro.
2001When used after physical formatting macros like
2002.Ic \&Em
2003or
2004.Ic \&Sy ,
2005switches back to the standard font face and weight.
2006Can also be used to embed plain text strings in macro lines
2007using semantic annotation macros.
2008.Pp
2009Examples:
2010.Dl ".Em italic , Sy bold , No and roman"
2011.Bd -literal -offset indent
2012\&.Sm off
2013\&.Cm :C No / Ar pattern No / Ar replacement No /
2014\&.Sm on
2015.Ed
2016.Pp
2017See also
2018.Ic \&Em ,
2019.Ic \&Ql ,
2020and
2021.Ic \&Sy .
2022.Tg Ns
2023.It Ic \&Ns
2024Suppress a space between the output of the preceding macro
2025and the following text or macro.
2026Following invocation, input is interpreted as normal text
2027just like after an
2028.Ic \&No
2029macro.
2030.Pp
2031This has no effect when invoked at the start of a macro line.
2032.Pp
2033Examples:
2034.Dl ".Ar name Ns = Ns Ar value"
2035.Dl ".Cm :M Ns Ar pattern"
2036.Dl ".Fl o Ns Ar output"
2037.Pp
2038See also
2039.Ic \&No
2040and
2041.Ic \&Sm .
2042.Tg Nx
2043.It Ic \&Nx Op Ar version
2044Format the
2045.Nx
2046version provided as an argument, or a default value if
2047no argument is provided.
2048.Pp
2049Examples:
2050.Dl \&.Nx 5.01
2051.Dl \&.Nx
2052.Pp
2053See also
2054.Ic \&At ,
2055.Ic \&Bsx ,
2056.Ic \&Bx ,
2057.Ic \&Dx ,
2058.Ic \&Fx ,
2059and
2060.Ic \&Ox .
2061.It Ic \&Oc
2062Close multi-line
2063.Ic \&Oo
2064context.
2065.It Ic \&Oo Ar block
2066Multi-line version of
2067.Ic \&Op .
2068.Pp
2069Examples:
2070.Bd -literal -offset indent -compact
2071\&.Oo
2072\&.Op Fl flag Ns Ar value
2073\&.Oc
2074.Ed
2075.Tg Op
2076.It Ic \&Op Ar line
2077Optional part of a command line.
2078Prints the argument(s) in brackets.
2079This is most often used in the
2080.Em SYNOPSIS
2081section of section 1 and 8 manual pages.
2082.Pp
2083Examples:
2084.Dl \&.Op \&Fl a \&Ar b
2085.Dl \&.Op \&Ar a | b
2086.Pp
2087See also
2088.Ic \&Oo .
2089.Tg Os
2090.It Ic \&Os Op Ar system Op Ar version
2091Operating system version for display in the page footer.
2092This is the mandatory third macro of
2093any
2094.Nm
2095file.
2096.Pp
2097The optional
2098.Ar system
2099parameter specifies the relevant operating system or environment.
2100It is suggested to leave it unspecified, in which case
2101.Xr mandoc 1
2102uses its
2103.Fl Ios
2104argument or, if that isn't specified either,
2105.Fa sysname
2106and
2107.Fa release
2108as returned by
2109.Xr uname 3 .
2110.Pp
2111Examples:
2112.Dl \&.Os
2113.Dl \&.Os KTH/CSC/TCS
2114.Dl \&.Os BSD 4.3
2115.Pp
2116See also
2117.Ic \&Dd
2118and
2119.Ic \&Dt .
2120.It Ic \&Ot Ar functype
2121This macro is obsolete.
2122Use
2123.Ic \&Ft
2124instead; with
2125.Xr mandoc 1 ,
2126both have the same effect.
2127.Pp
2128Historical
2129.Nm
2130packages described it as
2131.Dq "old function type (FORTRAN)" .
2132.Tg Ox
2133.It Ic \&Ox Op Ar version
2134Format the
2135.Ox
2136version provided as an argument, or a default value
2137if no argument is provided.
2138.Pp
2139Examples:
2140.Dl \&.Ox 4.5
2141.Dl \&.Ox
2142.Pp
2143See also
2144.Ic \&At ,
2145.Ic \&Bsx ,
2146.Ic \&Bx ,
2147.Ic \&Dx ,
2148.Ic \&Fx ,
2149and
2150.Ic \&Nx .
2151.Tg Pa
2152.It Ic \&Pa Ar name ...
2153An absolute or relative file system path, or a file or directory name.
2154If an argument is not provided, the character
2155.Sq \(ti
2156is used as a default.
2157.Pp
2158Examples:
2159.Dl \&.Pa /usr/bin/mandoc
2160.Dl \&.Pa /usr/share/man/man7/mdoc.7
2161.Pp
2162See also
2163.Ic \&Lk .
2164.It Ic \&Pc
2165Close parenthesised context opened by
2166.Ic \&Po .
2167.Tg Pf
2168.It Ic \&Pf Ar prefix macro Op Ar argument ...
2169Removes the space between its argument and the following macro.
2170It is equivalent to:
2171.Pp
2172.D1 Ic \&No Pf \e& Ar prefix Ic \&Ns Ar macro Op Ar argument ...
2173.Pp
2174The
2175.Ar prefix
2176argument is not parsed for macro names or delimiters,
2177but used verbatim as if it were escaped.
2178.Pp
2179Examples:
2180.Dl ".Pf $ Ar variable_name"
2181.Dl ".Pf . Ar macro_name"
2182.Dl ".Pf 0x Ar hex_digits"
2183.Pp
2184See also
2185.Ic \&Ns
2186and
2187.Ic \&Sm .
2188.It Ic \&Po Ar block
2189Multi-line version of
2190.Ic \&Pq .
2191.Tg Pp
2192.It Ic \&Pp
2193Break a paragraph.
2194This will assert vertical space between prior and subsequent macros
2195and/or text.
2196.Pp
2197Paragraph breaks are not needed before or after
2198.Ic \&Sh
2199or
2200.Ic \&Ss
2201macros or before displays
2202.Pq Ic \&Bd Ar line
2203or lists
2204.Pq Ic \&Bl
2205unless the
2206.Fl compact
2207flag is given.
2208.Tg Pq
2209.It Ic \&Pq Ar line
2210Parenthesised enclosure.
2211.Pp
2212See also
2213.Ic \&Po .
2214.It Ic \&Qc
2215Close quoted context opened by
2216.Ic \&Qo .
2217.Tg Ql
2218.It Ic \&Ql Ar line
2219In-line literal display.
2220This can be used for complete command invocations and for multi-word
2221code examples when an indented display is not desired.
2222.Pp
2223See also
2224.Ic \&Dl
2225and
2226.Ic \&Bd
2227.Fl literal .
2228.It Ic \&Qo Ar block
2229Multi-line version of
2230.Ic \&Qq .
2231.Tg Qq
2232.It Ic \&Qq Ar line
2233Encloses its arguments in
2234.Qq typewriter
2235double-quotes.
2236Consider using
2237.Ic \&Dq .
2238.Pp
2239See also
2240.Ic \&Dq ,
2241.Ic \&Sq ,
2242and
2243.Ic \&Qo .
2244.It Ic \&Re
2245Close an
2246.Ic \&Rs
2247block.
2248Does not have any tail arguments.
2249.Tg Rs
2250.It Ic \&Rs
2251Begin a bibliographic
2252.Pq Dq reference
2253block.
2254Does not have any head arguments.
2255The block macro may only contain
2256.Ic \&%A ,
2257.Ic \&%B ,
2258.Ic \&%C ,
2259.Ic \&%D ,
2260.Ic \&%I ,
2261.Ic \&%J ,
2262.Ic \&%N ,
2263.Ic \&%O ,
2264.Ic \&%P ,
2265.Ic \&%Q ,
2266.Ic \&%R ,
2267.Ic \&%T ,
2268.Ic \&%U ,
2269and
2270.Ic \&%V
2271child macros (at least one must be specified).
2272.Pp
2273Examples:
2274.Bd -literal -offset indent -compact
2275\&.Rs
2276\&.%A J. E. Hopcroft
2277\&.%A J. D. Ullman
2278\&.%B Introduction to Automata Theory, Languages, and Computation
2279\&.%I Addison-Wesley
2280\&.%C Reading, Massachusetts
2281\&.%D 1979
2282\&.Re
2283.Ed
2284.Pp
2285If an
2286.Ic \&Rs
2287block is used within a SEE ALSO section, a vertical space is asserted
2288before the rendered output, else the block continues on the current
2289line.
2290.Tg Rv
2291.It Ic \&Rv Fl std Op Ar function ...
2292Insert a standard sentence regarding a function call's return value of 0
2293on success and \-1 on error, with the
2294.Va errno
2295libc global variable set on error.
2296.Pp
2297If
2298.Ar function
2299is not specified, the document's name set by
2300.Ic \&Nm
2301is used.
2302Multiple
2303.Ar function
2304arguments are treated as separate functions.
2305.Pp
2306See also
2307.Ic \&Ex .
2308.It Ic \&Sc
2309Close single-quoted context opened by
2310.Ic \&So .
2311.Tg Sh
2312.It Ic \&Sh Ar TITLE LINE
2313Begin a new section.
2314For a list of conventional manual sections, see
2315.Sx MANUAL STRUCTURE .
2316These sections should be used unless it's absolutely necessary that
2317custom sections be used.
2318.Pp
2319Section names should be unique so that they may be keyed by
2320.Ic \&Sx .
2321Although this macro is parsed, it should not consist of child node or it
2322may not be linked with
2323.Ic \&Sx .
2324.Pp
2325See also
2326.Ic \&Pp ,
2327.Ic \&Ss ,
2328and
2329.Ic \&Sx .
2330.Tg Sm
2331.It Ic \&Sm Op Cm on | off
2332Switches the spacing mode for output generated from macros.
2333.Pp
2334By default, spacing is
2335.Cm on .
2336When switched
2337.Cm off ,
2338no white space is inserted between macro arguments and between the
2339output generated from adjacent macros, but text lines
2340still get normal spacing between words and sentences.
2341.Pp
2342When called without an argument, the
2343.Ic \&Sm
2344macro toggles the spacing mode.
2345Using this is not recommended because it makes the code harder to read.
2346.It Ic \&So Ar block
2347Multi-line version of
2348.Ic \&Sq .
2349.Tg Sq
2350.It Ic \&Sq Ar line
2351Encloses its arguments in
2352.Sq typewriter
2353single-quotes.
2354.Pp
2355See also
2356.Ic \&Dq ,
2357.Ic \&Qq ,
2358and
2359.Ic \&So .
2360.Tg Ss
2361.It Ic \&Ss Ar Title line
2362Begin a new subsection.
2363Unlike with
2364.Ic \&Sh ,
2365there is no convention for the naming of subsections.
2366Except
2367.Em DESCRIPTION ,
2368the conventional sections described in
2369.Sx MANUAL STRUCTURE
2370rarely have subsections.
2371.Pp
2372Sub-section names should be unique so that they may be keyed by
2373.Ic \&Sx .
2374Although this macro is parsed, it should not consist of child node or it
2375may not be linked with
2376.Ic \&Sx .
2377.Pp
2378See also
2379.Ic \&Pp ,
2380.Ic \&Sh ,
2381and
2382.Ic \&Sx .
2383.Tg St
2384.It Ic \&St Fl Ns Ar abbreviation
2385Replace an abbreviation for a standard with the full form.
2386The following standards are recognised.
2387Where multiple lines are given without a blank line in between,
2388they all refer to the same standard, and using the first form
2389is recommended.
2390.Bl -tag -width 1n
2391.It C language standards
2392.Pp
2393.Bl -tag -width "-p1003.1g-2000" -compact
2394.It \-ansiC
2395.St -ansiC
2396.It \-ansiC-89
2397.St -ansiC-89
2398.It \-isoC
2399.St -isoC
2400.It \-isoC-90
2401.St -isoC-90
2402.br
2403The original C standard.
2404.Pp
2405.It \-isoC-amd1
2406.St -isoC-amd1
2407.Pp
2408.It \-isoC-tcor1
2409.St -isoC-tcor1
2410.Pp
2411.It \-isoC-tcor2
2412.St -isoC-tcor2
2413.Pp
2414.It \-isoC-99
2415.St -isoC-99
2416.br
2417The second major version of the C language standard.
2418.Pp
2419.It \-isoC-2011
2420.St -isoC-2011
2421.br
2422The third major version of the C language standard.
2423.El
2424.It POSIX.1 before the Single UNIX Specification
2425.Pp
2426.Bl -tag -width "-p1003.1g-2000" -compact
2427.It \-p1003.1-88
2428.St -p1003.1-88
2429.It \-p1003.1
2430.St -p1003.1
2431.br
2432The original POSIX standard, based on ANSI C.
2433.Pp
2434.It \-p1003.1-90
2435.St -p1003.1-90
2436.It \-iso9945-1-90
2437.St -iso9945-1-90
2438.br
2439The first update of POSIX.1.
2440.Pp
2441.It \-p1003.1b-93
2442.St -p1003.1b-93
2443.It \-p1003.1b
2444.St -p1003.1b
2445.br
2446Real-time extensions.
2447.Pp
2448.It \-p1003.1c-95
2449.St -p1003.1c-95
2450.br
2451POSIX thread interfaces.
2452.Pp
2453.It \-p1003.1i-95
2454.St -p1003.1i-95
2455.br
2456Technical Corrigendum.
2457.Pp
2458.It \-p1003.1-96
2459.St -p1003.1-96
2460.It \-iso9945-1-96
2461.St -iso9945-1-96
2462.br
2463Includes POSIX.1-1990, 1b, 1c, and 1i.
2464.El
2465.It X/Open Portability Guide version 4 and related standards
2466.Pp
2467.Bl -tag -width "-p1003.1g-2000" -compact
2468.It \-xpg3
2469.St -xpg3
2470.br
2471An XPG4 precursor, published in 1989.
2472.Pp
2473.It \-p1003.2
2474.St -p1003.2
2475.It \-p1003.2-92
2476.St -p1003.2-92
2477.It \-iso9945-2-93
2478.St -iso9945-2-93
2479.br
2480An XCU4 precursor.
2481.Pp
2482.It \-p1003.2a-92
2483.St -p1003.2a-92
2484.br
2485Updates to POSIX.2.
2486.Pp
2487.It \-xpg4
2488.St -xpg4
2489.br
2490Based on POSIX.1 and POSIX.2, published in 1992.
2491.El
2492.It Single UNIX Specification version 1 and related standards
2493.Pp
2494.Bl -tag -width "-p1003.1g-2000" -compact
2495.It \-susv1
2496.St -susv1
2497.It \-xpg4.2
2498.St -xpg4.2
2499.br
2500This standard was published in 1994.
2501It was used as the basis for UNIX 95 certification.
2502The following three refer to parts of it.
2503.Pp
2504.It \-xsh4.2
2505.St -xsh4.2
2506.Pp
2507.It \-xcurses4.2
2508.St -xcurses4.2
2509.Pp
2510.It \-p1003.1g-2000
2511.St -p1003.1g-2000
2512.br
2513Networking APIs, including sockets.
2514.Pp
2515.It \-svid4
2516.St -svid4 ,
2517.br
2518Published in 1995.
2519.El
2520.It Single UNIX Specification version 2 and related standards
2521.Pp
2522.Bl -tag -width "-p1003.1g-2000" -compact
2523.It \-susv2
2524.St -susv2
2525This Standard was published in 1997
2526and is also called X/Open Portability Guide version 5.
2527It was used as the basis for UNIX 98 certification.
2528The following refer to parts of it.
2529.Pp
2530.It \-xbd5
2531.St -xbd5
2532.Pp
2533.It \-xsh5
2534.St -xsh5
2535.Pp
2536.It \-xcu5
2537.St -xcu5
2538.Pp
2539.It \-xns5
2540.St -xns5
2541.It \-xns5.2
2542.St -xns5.2
2543.El
2544.It Single UNIX Specification version 3
2545.Pp
2546.Bl -tag -width "-p1003.1-2001" -compact
2547.It \-p1003.1-2001
2548.St -p1003.1-2001
2549.It \-susv3
2550.St -susv3
2551.br
2552This standard is based on C99, SUSv2, POSIX.1-1996, 1d, and 1j.
2553It is also called X/Open Portability Guide version 6.
2554It is used as the basis for UNIX 03 certification.
2555.Pp
2556.It \-p1003.1-2004
2557.St -p1003.1-2004
2558.br
2559The second and last Technical Corrigendum.
2560.El
2561.It Single UNIX Specification version 4
2562.Pp
2563.Bl -tag -width "-p1003.1g-2000" -compact
2564.It \-p1003.1-2008
2565.St -p1003.1-2008
2566.It \-susv4
2567.St -susv4
2568.br
2569This standard is also called
2570X/Open Portability Guide version 7.
2571.El
2572.It Other standards
2573.Pp
2574.Bl -tag -width "-p1003.1g-2000" -compact
2575.It \-ieee754
2576.St -ieee754
2577.br
2578Floating-point arithmetic.
2579.Pp
2580.It \-iso8601
2581.St -iso8601
2582.br
2583Representation of dates and times, published in 1988.
2584.Pp
2585.It \-iso8802-3
2586.St -iso8802-3
2587.br
2588Ethernet local area networks.
2589.Pp
2590.It \-ieee1275-94
2591.St -ieee1275-94
2592.El
2593.El
2594.Tg Sx
2595.It Ic \&Sx Ar Title line
2596Reference a section or subsection in the same manual page.
2597The referenced section or subsection name must be identical to the
2598enclosed argument, including whitespace.
2599.Pp
2600Examples:
2601.Dl \&.Sx MANUAL STRUCTURE
2602.Pp
2603See also
2604.Ic \&Sh
2605and
2606.Ic \&Ss .
2607.Tg Sy
2608.It Ic \&Sy Ar word ...
2609Request a boldface font.
2610.Pp
2611This is most often used to indicate importance or seriousness (not to be
2612confused with stress emphasis, see
2613.Ic \&Em ) .
2614When none of the semantic macros fit, it is also adequate for syntax
2615elements that have to be given or that appear verbatim.
2616.Pp
2617Examples:
2618.Bd -literal -compact -offset indent
2619\&.Sy Warning :
2620If
2621\&.Sy s
2622appears in the owner permissions, set-user-ID mode is set.
2623This utility replaces the former
2624\&.Sy dumpdir
2625program.
2626.Ed
2627.Pp
2628See also
2629.Ic \&Em ,
2630.Ic \&No ,
2631and
2632.Ic \&Ql .
2633.Tg Ta
2634.It Ic \&Ta
2635Table cell separator in
2636.Ic \&Bl Fl column
2637lists; can only be used below
2638.Ic \&It .
2639.Tg Tg
2640.It Ic \&Tg Op Ar term
2641Announce that the next input line starts a definition of the
2642.Ar term .
2643This macro must appear alone on its own input line.
2644The argument defaults to the first argument of the first macro
2645on the next line.
2646The argument may not contain whitespace characters, not even when it is quoted.
2647This macro is a
2648.Xr mandoc 1
2649extension and is typically ignored by other formatters.
2650.Pp
2651When viewing terminal output with
2652.Xr less 1 ,
2653the interactive
2654.Ic :t
2655command can be used to go to the definition of the
2656.Ar term
2657as described for the
2658.Ev MANPAGER
2659variable in
2660.Xr man 1 ;
2661when producing HTML output, a fragment identifier
2662.Pq Ic id No attribute
2663is generated, to be used for deep linking to this place of the document.
2664.Pp
2665In most cases, adding a
2666.Ic \&Tg
2667macro would be redundant because
2668.Xr mandoc 1
2669is able to automatically tag most definitions.
2670This macro is intended for cases where automatic tagging of a
2671.Ar term
2672is unsatisfactory, for example if a definition is not tagged
2673automatically (false negative) or if places are tagged that do
2674not define the
2675.Ar term
2676(false positives).
2677When there is at least one
2678.Ic \&Tg
2679macro for a
2680.Ar term ,
2681no other places are automatically marked as definitions of that
2682.Ar term .
2683.It Ic \&Tn Ar word ...
2684Supported only for compatibility, do not use this in new manuals.
2685Even though the macro name
2686.Pq Dq tradename
2687suggests a semantic function, historic usage is inconsistent, mostly
2688using it as a presentation-level macro to request a small caps font.
2689.It Ic \&Ud
2690Supported only for compatibility, do not use this in new manuals.
2691Prints out
2692.Dq currently under development.
2693.It Ic \&Ux
2694Supported only for compatibility, do not use this in new manuals.
2695Prints out
2696.Dq Ux .
2697.Tg Va
2698.It Ic \&Va Oo Ar type Oc Ar identifier ...
2699A variable name.
2700.Pp
2701Examples:
2702.Dl \&.Va foo
2703.Dl \&.Va const char *bar ;
2704.Pp
2705For function arguments and parameters, use
2706.Ic \&Fa
2707instead.
2708For declarations of global variables in the
2709.Em SYNOPSIS
2710section, use
2711.Ic \&Vt .
2712.Tg Vt
2713.It Ic \&Vt Ar type Op Ar identifier
2714A variable type.
2715.Pp
2716This is also used for indicating global variables in the
2717.Em SYNOPSIS
2718section, in which case a variable name is also specified.
2719Note that it accepts
2720.Sx Block partial-implicit
2721syntax when invoked as the first macro on an input line in the
2722.Em SYNOPSIS
2723section, else it accepts ordinary
2724.Sx In-line
2725syntax.
2726In the former case, this macro starts a new output line,
2727and a blank line is inserted in front if there is a preceding
2728function definition or include directive.
2729.Pp
2730Examples:
2731.Dl \&.Vt unsigned char
2732.Dl \&.Vt extern const char * const sys_signame[] \&;
2733.Pp
2734For parameters in function prototypes, use
2735.Ic \&Fa
2736instead, for function return types
2737.Ic \&Ft ,
2738and for variable names outside the
2739.Em SYNOPSIS
2740section
2741.Ic \&Va ,
2742even when including a type with the name.
2743See also
2744.Sx MANUAL STRUCTURE .
2745.It Ic \&Xc
2746Close a scope opened by
2747.Ic \&Xo .
2748.It Ic \&Xo Ar block
2749Extend the header of an
2750.Ic \&It
2751macro or the body of a partial-implicit block macro
2752beyond the end of the input line.
2753This macro originally existed to work around the 9-argument limit
2754of historic
2755.Xr roff 7 .
2756.Tg Xr
2757.It Ic \&Xr Ar name section
2758Link to another manual
2759.Pq Qq cross-reference .
2760.Pp
2761Cross reference the
2762.Ar name
2763and
2764.Ar section
2765number of another man page.
2766.Pp
2767Examples:
2768.Dl \&.Xr mandoc 1
2769.Dl \&.Xr mandoc 1 \&;
2770.Dl \&.Xr mandoc 1 \&Ns s behaviour
2771.El
2772.Sh MACRO SYNTAX
2773The syntax of a macro depends on its classification.
2774In this section,
2775.Sq \-arg
2776refers to macro arguments, which may be followed by zero or more
2777.Sq parm
2778parameters;
2779.Sq \&Yo
2780opens the scope of a macro; and if specified,
2781.Sq \&Yc
2782closes it out.
2783.Pp
2784The
2785.Em Callable
2786column indicates that the macro may also be called by passing its name
2787as an argument to another macro.
2788For example,
2789.Sq \&.Op \&Fl O \&Ar file
2790produces
2791.Sq Op Fl O Ar file .
2792To prevent a macro call and render the macro name literally,
2793escape it by prepending a zero-width space,
2794.Sq \e& .
2795For example,
2796.Sq \&Op \e&Fl O
2797produces
2798.Sq Op \&Fl O .
2799If a macro is not callable but its name appears as an argument
2800to another macro, it is interpreted as opaque text.
2801For example,
2802.Sq \&.Fl \&Sh
2803produces
2804.Sq Fl \&Sh .
2805.Pp
2806The
2807.Em Parsed
2808column indicates whether the macro may call other macros by receiving
2809their names as arguments.
2810If a macro is not parsed but the name of another macro appears
2811as an argument, it is interpreted as opaque text.
2812.Pp
2813The
2814.Em Scope
2815column, if applicable, describes closure rules.
2816.Ss Block full-explicit
2817Multi-line scope closed by an explicit closing macro.
2818All macros contains bodies; only
2819.Ic \&Bf
2820and
2821.Pq optionally
2822.Ic \&Bl
2823contain a head.
2824.Bd -literal -offset indent
2825\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
2826\(lBbody...\(rB
2827\&.Yc
2828.Ed
2829.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXX" -offset indent
2830.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2831.It Ic \&Bd  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ed
2832.It Ic \&Bf  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ef
2833.It Ic \&Bk  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Ek
2834.It Ic \&Bl  Ta    \&No     Ta    \&No     Ta    closed by Ic \&El
2835.It Ic \&Ed  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bd
2836.It Ic \&Ef  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bf
2837.It Ic \&Ek  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bk
2838.It Ic \&El  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Bl
2839.El
2840.Ss Block full-implicit
2841Multi-line scope closed by end-of-file or implicitly by another macro.
2842All macros have bodies; some
2843.Po
2844.Ic \&It Fl bullet ,
2845.Fl hyphen ,
2846.Fl dash ,
2847.Fl enum ,
2848.Fl item
2849.Pc
2850don't have heads; only one
2851.Po
2852.Ic \&It
2853in
2854.Ic \&Bl Fl column
2855.Pc
2856has multiple heads.
2857.Bd -literal -offset indent
2858\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB
2859\(lBbody...\(rB
2860.Ed
2861.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXXXXXXXXX" -offset indent
2862.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2863.It Ic \&It Ta \&No Ta Yes  Ta closed by Ic \&It , Ic \&El
2864.It Ic \&Nd Ta \&No Ta \&No Ta closed by Ic \&Sh
2865.It Ic \&Nm Ta \&No Ta Yes  Ta closed by Ic \&Nm , Ic \&Sh , Ic \&Ss
2866.It Ic \&Sh Ta \&No Ta Yes  Ta closed by Ic \&Sh
2867.It Ic \&Ss Ta \&No Ta Yes  Ta closed by Ic \&Sh , Ic \&Ss
2868.El
2869.Pp
2870Note that the
2871.Ic \&Nm
2872macro is a
2873.Sx Block full-implicit
2874macro only when invoked as the first macro
2875in a
2876.Em SYNOPSIS
2877section line, else it is
2878.Sx In-line .
2879.Ss Block partial-explicit
2880Like block full-explicit, but also with single-line scope.
2881Each has at least a body and, in limited circumstances, a head
2882.Po
2883.Ic \&Fo ,
2884.Ic \&Eo
2885.Pc
2886and/or tail
2887.Pq Ic \&Ec .
2888.Bd -literal -offset indent
2889\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
2890\(lBbody...\(rB
2891\&.Yc \(lBtail...\(rB
2892
2893\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \
2894\(lBbody...\(rB \&Yc \(lBtail...\(rB
2895.Ed
2896.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
2897.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2898.It Ic \&Ac  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Ao
2899.It Ic \&Ao  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Ac
2900.It Ic \&Bc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Bo
2901.It Ic \&Bo  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Bc
2902.It Ic \&Brc Ta    Yes      Ta    Yes      Ta    opened by Ic \&Bro
2903.It Ic \&Bro Ta    Yes      Ta    Yes      Ta    closed by Ic \&Brc
2904.It Ic \&Dc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Do
2905.It Ic \&Do  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Dc
2906.It Ic \&Ec  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Eo
2907.It Ic \&Eo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Ec
2908.It Ic \&Fc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Fo
2909.It Ic \&Fo  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Fc
2910.It Ic \&Oc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Oo
2911.It Ic \&Oo  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Oc
2912.It Ic \&Pc  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Po
2913.It Ic \&Po  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Pc
2914.It Ic \&Qc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Oo
2915.It Ic \&Qo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Oc
2916.It Ic \&Re  Ta    \&No     Ta    \&No     Ta    opened by Ic \&Rs
2917.It Ic \&Rs  Ta    \&No     Ta    \&No     Ta    closed by Ic \&Re
2918.It Ic \&Sc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&So
2919.It Ic \&So  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Sc
2920.It Ic \&Xc  Ta    Yes      Ta    Yes      Ta    opened by Ic \&Xo
2921.It Ic \&Xo  Ta    Yes      Ta    Yes      Ta    closed by Ic \&Xc
2922.El
2923.Ss Block partial-implicit
2924Like block full-implicit, but with single-line scope closed by the
2925end of the line.
2926.Bd -literal -offset indent
2927\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB
2928.Ed
2929.Bl -column "MacroX" "CallableX" "ParsedX" -offset indent
2930.It Em Macro Ta Em Callable Ta Em Parsed
2931.It Ic \&Aq  Ta    Yes      Ta    Yes
2932.It Ic \&Bq  Ta    Yes      Ta    Yes
2933.It Ic \&Brq Ta    Yes      Ta    Yes
2934.It Ic \&D1  Ta    \&No     Ta    \&Yes
2935.It Ic \&Dl  Ta    \&No     Ta    Yes
2936.It Ic \&Dq  Ta    Yes      Ta    Yes
2937.It Ic \&En  Ta    Yes      Ta    Yes
2938.It Ic \&Op  Ta    Yes      Ta    Yes
2939.It Ic \&Pq  Ta    Yes      Ta    Yes
2940.It Ic \&Ql  Ta    Yes      Ta    Yes
2941.It Ic \&Qq  Ta    Yes      Ta    Yes
2942.It Ic \&Sq  Ta    Yes      Ta    Yes
2943.It Ic \&Vt  Ta    Yes      Ta    Yes
2944.El
2945.Pp
2946Note that the
2947.Ic \&Vt
2948macro is a
2949.Sx Block partial-implicit
2950only when invoked as the first macro
2951in a
2952.Em SYNOPSIS
2953section line, else it is
2954.Sx In-line .
2955.Ss Special block macro
2956The
2957.Ic \&Ta
2958macro can only be used below
2959.Ic \&It
2960in
2961.Ic \&Bl Fl column
2962lists.
2963It delimits blocks representing table cells;
2964these blocks have bodies, but no heads.
2965.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
2966.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
2967.It Ic \&Ta  Ta    Yes      Ta    Yes    Ta closed by Ic \&Ta , Ic \&It
2968.El
2969.Ss In-line
2970Closed by the end of the line, fixed argument lengths,
2971and/or subsequent macros.
2972In-line macros have only text children.
2973If a number (or inequality) of arguments is
2974.Pq n ,
2975then the macro accepts an arbitrary number of arguments.
2976.Bd -literal -offset indent
2977\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB \(lBres...\(rB
2978
2979\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc...
2980
2981\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
2982.Ed
2983.Bl -column "MacroX" "CallableX" "ParsedX" "Arguments" -offset indent
2984.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Arguments
2985.It Ic \&%A  Ta    \&No     Ta    \&No     Ta    >0
2986.It Ic \&%B  Ta    \&No     Ta    \&No     Ta    >0
2987.It Ic \&%C  Ta    \&No     Ta    \&No     Ta    >0
2988.It Ic \&%D  Ta    \&No     Ta    \&No     Ta    >0
2989.It Ic \&%I  Ta    \&No     Ta    \&No     Ta    >0
2990.It Ic \&%J  Ta    \&No     Ta    \&No     Ta    >0
2991.It Ic \&%N  Ta    \&No     Ta    \&No     Ta    >0
2992.It Ic \&%O  Ta    \&No     Ta    \&No     Ta    >0
2993.It Ic \&%P  Ta    \&No     Ta    \&No     Ta    >0
2994.It Ic \&%Q  Ta    \&No     Ta    \&No     Ta    >0
2995.It Ic \&%R  Ta    \&No     Ta    \&No     Ta    >0
2996.It Ic \&%T  Ta    \&No     Ta    \&No     Ta    >0
2997.It Ic \&%U  Ta    \&No     Ta    \&No     Ta    >0
2998.It Ic \&%V  Ta    \&No     Ta    \&No     Ta    >0
2999.It Ic \&Ad  Ta    Yes      Ta    Yes      Ta    >0
3000.It Ic \&An  Ta    Yes      Ta    Yes      Ta    >0
3001.It Ic \&Ap  Ta    Yes      Ta    Yes      Ta    0
3002.It Ic \&Ar  Ta    Yes      Ta    Yes      Ta    n
3003.It Ic \&At  Ta    Yes      Ta    Yes      Ta    1
3004.It Ic \&Bsx Ta    Yes      Ta    Yes      Ta    n
3005.It Ic \&Bt  Ta    \&No     Ta    \&No     Ta    0
3006.It Ic \&Bx  Ta    Yes      Ta    Yes      Ta    n
3007.It Ic \&Cd  Ta    Yes      Ta    Yes      Ta    >0
3008.It Ic \&Cm  Ta    Yes      Ta    Yes      Ta    >0
3009.It Ic \&Db  Ta    \&No     Ta    \&No     Ta    1
3010.It Ic \&Dd  Ta    \&No     Ta    \&No     Ta    n
3011.It Ic \&Dt  Ta    \&No     Ta    \&No     Ta    n
3012.It Ic \&Dv  Ta    Yes      Ta    Yes      Ta    >0
3013.It Ic \&Dx  Ta    Yes      Ta    Yes      Ta    n
3014.It Ic \&Em  Ta    Yes      Ta    Yes      Ta    >0
3015.It Ic \&Er  Ta    Yes      Ta    Yes      Ta    >0
3016.It Ic \&Es  Ta    Yes      Ta    Yes      Ta    2
3017.It Ic \&Ev  Ta    Yes      Ta    Yes      Ta    >0
3018.It Ic \&Ex  Ta    \&No     Ta    \&No     Ta    n
3019.It Ic \&Fa  Ta    Yes      Ta    Yes      Ta    >0
3020.It Ic \&Fd  Ta    \&No     Ta    \&No     Ta    >0
3021.It Ic \&Fl  Ta    Yes      Ta    Yes      Ta    n
3022.It Ic \&Fn  Ta    Yes      Ta    Yes      Ta    >0
3023.It Ic \&Fr  Ta    Yes      Ta    Yes      Ta    >0
3024.It Ic \&Ft  Ta    Yes      Ta    Yes      Ta    >0
3025.It Ic \&Fx  Ta    Yes      Ta    Yes      Ta    n
3026.It Ic \&Hf  Ta    \&No     Ta    \&No     Ta    n
3027.It Ic \&Ic  Ta    Yes      Ta    Yes      Ta    >0
3028.It Ic \&In  Ta    \&No     Ta    \&No     Ta    1
3029.It Ic \&Lb  Ta    \&No     Ta    \&No     Ta    1
3030.It Ic \&Li  Ta    Yes      Ta    Yes      Ta    >0
3031.It Ic \&Lk  Ta    Yes      Ta    Yes      Ta    >0
3032.It Ic \&Lp  Ta    \&No     Ta    \&No     Ta    0
3033.It Ic \&Ms  Ta    Yes      Ta    Yes      Ta    >0
3034.It Ic \&Mt  Ta    Yes      Ta    Yes      Ta    >0
3035.It Ic \&Nm  Ta    Yes      Ta    Yes      Ta    n
3036.It Ic \&No  Ta    Yes      Ta    Yes      Ta    >0
3037.It Ic \&Ns  Ta    Yes      Ta    Yes      Ta    0
3038.It Ic \&Nx  Ta    Yes      Ta    Yes      Ta    n
3039.It Ic \&Os  Ta    \&No     Ta    \&No     Ta    n
3040.It Ic \&Ot  Ta    Yes      Ta    Yes      Ta    >0
3041.It Ic \&Ox  Ta    Yes      Ta    Yes      Ta    n
3042.It Ic \&Pa  Ta    Yes      Ta    Yes      Ta    n
3043.It Ic \&Pf  Ta    Yes      Ta    Yes      Ta    1
3044.It Ic \&Pp  Ta    \&No     Ta    \&No     Ta    0
3045.It Ic \&Rv  Ta    \&No     Ta    \&No     Ta    n
3046.It Ic \&Sm  Ta    \&No     Ta    \&No     Ta    <2
3047.It Ic \&St  Ta    \&No     Ta    Yes      Ta    1
3048.It Ic \&Sx  Ta    Yes      Ta    Yes      Ta    >0
3049.It Ic \&Sy  Ta    Yes      Ta    Yes      Ta    >0
3050.It Ic \&Tg  Ta    \&No     Ta    \&No     Ta    <2
3051.It Ic \&Tn  Ta    Yes      Ta    Yes      Ta    >0
3052.It Ic \&Ud  Ta    \&No     Ta    \&No     Ta    0
3053.It Ic \&Ux  Ta    Yes      Ta    Yes      Ta    n
3054.It Ic \&Va  Ta    Yes      Ta    Yes      Ta    n
3055.It Ic \&Vt  Ta    Yes      Ta    Yes      Ta    >0
3056.It Ic \&Xr  Ta    Yes      Ta    Yes      Ta    2
3057.El
3058.Ss Delimiters
3059When a macro argument consists of one single input character
3060considered as a delimiter, the argument gets special handling.
3061This does not apply when delimiters appear in arguments containing
3062more than one character.
3063Consequently, to prevent special handling and just handle it
3064like any other argument, a delimiter can be escaped by prepending
3065a zero-width space
3066.Pq Sq \e& .
3067In text lines, delimiters never need escaping, but may be used
3068as normal punctuation.
3069.Pp
3070For many macros, when the leading arguments are opening delimiters,
3071these delimiters are put before the macro scope,
3072and when the trailing arguments are closing delimiters,
3073these delimiters are put after the macro scope.
3074Spacing is suppressed after opening delimiters
3075and before closing delimiters.
3076For example,
3077.Pp
3078.D1 Pf \. \&Aq "( [ word ] ) ."
3079.Pp
3080renders as:
3081.Pp
3082.D1 Aq ( [ word ] ) .
3083.Pp
3084Opening delimiters are:
3085.Pp
3086.Bl -tag -width Ds -offset indent -compact
3087.It \&(
3088left parenthesis
3089.It \&[
3090left bracket
3091.El
3092.Pp
3093Closing delimiters are:
3094.Pp
3095.Bl -tag -width Ds -offset indent -compact
3096.It \&.
3097period
3098.It \&,
3099comma
3100.It \&:
3101colon
3102.It \&;
3103semicolon
3104.It \&)
3105right parenthesis
3106.It \&]
3107right bracket
3108.It \&?
3109question mark
3110.It \&!
3111exclamation mark
3112.El
3113.Pp
3114Note that even a period preceded by a backslash
3115.Pq Sq \e.\&
3116gets this special handling; use
3117.Sq \e&.\&
3118to prevent that.
3119.Pp
3120Many in-line macros interrupt their scope when they encounter
3121delimiters, and resume their scope when more arguments follow that
3122are not delimiters.
3123For example,
3124.Pp
3125.D1 Pf \. \&Fl "a ( b | c \e*(Ba d ) e"
3126.Pp
3127renders as:
3128.Pp
3129.D1 Fl a ( b | c \*(Ba d ) e
3130.Pp
3131This applies to both opening and closing delimiters,
3132and also to the middle delimiter, which does not suppress spacing:
3133.Pp
3134.Bl -tag -width Ds -offset indent -compact
3135.It \&|
3136vertical bar
3137.El
3138.Pp
3139As a special case, the predefined string \e*(Ba is handled and rendered
3140in the same way as a plain
3141.Sq \&|
3142character.
3143Using this predefined string is not recommended in new manuals.
3144.Pp
3145Appending a zero-width space
3146.Pq Sq \e&
3147to the end of an input line is also useful to prevent the interpretation
3148of a trailing period, exclamation or question mark as the end of a
3149sentence, for example when an abbreviation happens to occur
3150at the end of a text or macro input line.
3151.Ss Font handling
3152In
3153.Nm
3154documents, usage of semantic markup is recommended in order to have
3155proper fonts automatically selected; only when no fitting semantic markup
3156is available, consider falling back to
3157.Sx Physical markup
3158macros.
3159Whenever any
3160.Nm
3161macro switches the
3162.Xr roff 7
3163font mode, it will automatically restore the previous font when exiting
3164its scope.
3165Manually switching the font using the
3166.Xr roff 7
3167.Ql \ef
3168font escape sequences is never required.
3169.Sh COMPATIBILITY
3170This section provides an incomplete list of compatibility issues
3171between mandoc and GNU troff
3172.Pq Qq groff .
3173.Pp
3174The following problematic behaviour is found in groff:
3175.Pp
3176.Bl -dash -compact
3177.It
3178.Ic \&Pa
3179does not format its arguments when used in the FILES section under
3180certain list types.
3181.It
3182.Ic \&Ta
3183can only be called by other macros, but not at the beginning of a line.
3184.It
3185.Sq \ef
3186.Pq font face
3187and
3188.Sq \eF
3189.Pq font family face
3190.Sx Text Decoration
3191escapes behave irregularly when specified within line-macro scopes.
3192.It
3193Negative scaling units return to prior lines.
3194Instead, mandoc truncates them to zero.
3195.El
3196.Pp
3197The following features are unimplemented in mandoc:
3198.Pp
3199.Bl -dash -compact
3200.It
3201.Ic \&Bd Fl file Ar file
3202is unsupported for security reasons.
3203.It
3204.Ic \&Bd
3205.Fl filled
3206does not adjust the right margin, but is an alias for
3207.Ic \&Bd
3208.Fl ragged .
3209.It
3210.Ic \&Bd
3211.Fl literal
3212does not use a literal font, but is an alias for
3213.Ic \&Bd
3214.Fl unfilled .
3215.It
3216.Ic \&Bd
3217.Fl offset Cm center
3218and
3219.Fl offset Cm right
3220don't work.
3221Groff does not implement centered and flush-right rendering either,
3222but produces large indentations.
3223.El
3224.Sh SEE ALSO
3225.Xr man 1 ,
3226.Xr mandoc 1 ,
3227.Xr eqn 7 ,
3228.Xr man 7 ,
3229.Xr mandoc_char 7 ,
3230.Xr roff 7 ,
3231.Xr tbl 7
3232.Pp
3233The web page
3234.Lk https://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language"
3235provides a few tutorial-style pages for beginners, an extensive style
3236guide for advanced authors, and an alphabetic index helping to choose
3237the best macros for various kinds of content.
3238.Pp
3239The manual page
3240.Lk https://man.voidlinux.org/groff_mdoc "groff_mdoc(7)"
3241contained in the
3242.Dq groff
3243package documents exactly the same language in a somewhat different style.
3244.Sh HISTORY
3245The
3246.Nm
3247language first appeared as a troff macro package in
3248.Bx 4.4 .
3249It was later significantly updated by Werner Lemberg and Ruslan Ermilov
3250in groff-1.17.
3251The standalone implementation that is part of the
3252.Xr mandoc 1
3253utility written by Kristaps Dzonsons appeared in
3254.Ox 4.6 .
3255.Sh AUTHORS
3256The
3257.Nm
3258reference was written by
3259.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
3260