1.\" $OpenBSD: mdoc.7,v 1.181 2022/01/13 08:39:24 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.Dd $Mdocdate: January 13 2022 $ 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 two refer to parts of it. 2503.Pp 2504.It \-xcurses4.2 2505.St -xcurses4.2 2506.Pp 2507.It \-p1003.1g-2000 2508.St -p1003.1g-2000 2509.br 2510Networking APIs, including sockets. 2511.Pp 2512.It \-svid4 2513.St -svid4 , 2514.br 2515Published in 1995. 2516.El 2517.It Single UNIX Specification version 2 and related standards 2518.Pp 2519.Bl -tag -width "-p1003.1g-2000" -compact 2520.It \-susv2 2521.St -susv2 2522This Standard was published in 1997 2523and is also called X/Open Portability Guide version 5. 2524It was used as the basis for UNIX 98 certification. 2525The following refer to parts of it. 2526.Pp 2527.It \-xbd5 2528.St -xbd5 2529.Pp 2530.It \-xsh5 2531.St -xsh5 2532.Pp 2533.It \-xcu5 2534.St -xcu5 2535.Pp 2536.It \-xns5 2537.St -xns5 2538.It \-xns5.2 2539.St -xns5.2 2540.El 2541.It Single UNIX Specification version 3 2542.Pp 2543.Bl -tag -width "-p1003.1-2001" -compact 2544.It \-p1003.1-2001 2545.St -p1003.1-2001 2546.It \-susv3 2547.St -susv3 2548.br 2549This standard is based on C99, SUSv2, POSIX.1-1996, 1d, and 1j. 2550It is also called X/Open Portability Guide version 6. 2551It is used as the basis for UNIX 03 certification. 2552.Pp 2553.It \-p1003.1-2004 2554.St -p1003.1-2004 2555.br 2556The second and last Technical Corrigendum. 2557.El 2558.It Single UNIX Specification version 4 2559.Pp 2560.Bl -tag -width "-p1003.1g-2000" -compact 2561.It \-p1003.1-2008 2562.St -p1003.1-2008 2563.It \-susv4 2564.St -susv4 2565.br 2566This standard is also called 2567X/Open Portability Guide version 7. 2568.El 2569.It Other standards 2570.Pp 2571.Bl -tag -width "-p1003.1g-2000" -compact 2572.It \-ieee754 2573.St -ieee754 2574.br 2575Floating-point arithmetic. 2576.Pp 2577.It \-iso8601 2578.St -iso8601 2579.br 2580Representation of dates and times, published in 1988. 2581.Pp 2582.It \-iso8802-3 2583.St -iso8802-3 2584.br 2585Ethernet local area networks. 2586.Pp 2587.It \-ieee1275-94 2588.St -ieee1275-94 2589.El 2590.El 2591.Tg Sx 2592.It Ic \&Sx Ar Title line 2593Reference a section or subsection in the same manual page. 2594The referenced section or subsection name must be identical to the 2595enclosed argument, including whitespace. 2596.Pp 2597Examples: 2598.Dl \&.Sx MANUAL STRUCTURE 2599.Pp 2600See also 2601.Ic \&Sh 2602and 2603.Ic \&Ss . 2604.Tg Sy 2605.It Ic \&Sy Ar word ... 2606Request a boldface font. 2607.Pp 2608This is most often used to indicate importance or seriousness (not to be 2609confused with stress emphasis, see 2610.Ic \&Em ) . 2611When none of the semantic macros fit, it is also adequate for syntax 2612elements that have to be given or that appear verbatim. 2613.Pp 2614Examples: 2615.Bd -literal -compact -offset indent 2616\&.Sy Warning : 2617If 2618\&.Sy s 2619appears in the owner permissions, set-user-ID mode is set. 2620This utility replaces the former 2621\&.Sy dumpdir 2622program. 2623.Ed 2624.Pp 2625See also 2626.Ic \&Em , 2627.Ic \&No , 2628and 2629.Ic \&Ql . 2630.Tg Ta 2631.It Ic \&Ta 2632Table cell separator in 2633.Ic \&Bl Fl column 2634lists; can only be used below 2635.Ic \&It . 2636.Tg Tg 2637.It Ic \&Tg Op Ar term 2638Announce that the next input line starts a definition of the 2639.Ar term . 2640This macro must appear alone on its own input line. 2641The argument defaults to the first argument of the first macro 2642on the next line. 2643The argument may not contain whitespace characters, not even when it is quoted. 2644This macro is a 2645.Xr mandoc 1 2646extension and is typically ignored by other formatters. 2647.Pp 2648When viewing terminal output with 2649.Xr less 1 , 2650the interactive 2651.Ic :t 2652command can be used to go to the definition of the 2653.Ar term 2654as described for the 2655.Ev MANPAGER 2656variable in 2657.Xr man 1 ; 2658when producing HTML output, a fragment identifier 2659.Pq Ic id No attribute 2660is generated, to be used for deep linking to this place of the document. 2661.Pp 2662In most cases, adding a 2663.Ic \&Tg 2664macro would be redundant because 2665.Xr mandoc 1 2666is able to automatically tag most definitions. 2667This macro is intended for cases where automatic tagging of a 2668.Ar term 2669is unsatisfactory, for example if a definition is not tagged 2670automatically (false negative) or if places are tagged that do 2671not define the 2672.Ar term 2673(false positives). 2674When there is at least one 2675.Ic \&Tg 2676macro for a 2677.Ar term , 2678no other places are automatically marked as definitions of that 2679.Ar term . 2680.It Ic \&Tn Ar word ... 2681Supported only for compatibility, do not use this in new manuals. 2682Even though the macro name 2683.Pq Dq tradename 2684suggests a semantic function, historic usage is inconsistent, mostly 2685using it as a presentation-level macro to request a small caps font. 2686.It Ic \&Ud 2687Supported only for compatibility, do not use this in new manuals. 2688Prints out 2689.Dq currently under development. 2690.It Ic \&Ux 2691Supported only for compatibility, do not use this in new manuals. 2692Prints out 2693.Dq Ux . 2694.Tg Va 2695.It Ic \&Va Oo Ar type Oc Ar identifier ... 2696A variable name. 2697.Pp 2698Examples: 2699.Dl \&.Va foo 2700.Dl \&.Va const char *bar ; 2701.Pp 2702For function arguments and parameters, use 2703.Ic \&Fa 2704instead. 2705For declarations of global variables in the 2706.Em SYNOPSIS 2707section, use 2708.Ic \&Vt . 2709.Tg Vt 2710.It Ic \&Vt Ar type Op Ar identifier 2711A variable type. 2712.Pp 2713This is also used for indicating global variables in the 2714.Em SYNOPSIS 2715section, in which case a variable name is also specified. 2716Note that it accepts 2717.Sx Block partial-implicit 2718syntax when invoked as the first macro on an input line in the 2719.Em SYNOPSIS 2720section, else it accepts ordinary 2721.Sx In-line 2722syntax. 2723In the former case, this macro starts a new output line, 2724and a blank line is inserted in front if there is a preceding 2725function definition or include directive. 2726.Pp 2727Examples: 2728.Dl \&.Vt unsigned char 2729.Dl \&.Vt extern const char * const sys_signame[] \&; 2730.Pp 2731For parameters in function prototypes, use 2732.Ic \&Fa 2733instead, for function return types 2734.Ic \&Ft , 2735and for variable names outside the 2736.Em SYNOPSIS 2737section 2738.Ic \&Va , 2739even when including a type with the name. 2740See also 2741.Sx MANUAL STRUCTURE . 2742.It Ic \&Xc 2743Close a scope opened by 2744.Ic \&Xo . 2745.It Ic \&Xo Ar block 2746Extend the header of an 2747.Ic \&It 2748macro or the body of a partial-implicit block macro 2749beyond the end of the input line. 2750This macro originally existed to work around the 9-argument limit 2751of historic 2752.Xr roff 7 . 2753.Tg Xr 2754.It Ic \&Xr Ar name section 2755Link to another manual 2756.Pq Qq cross-reference . 2757.Pp 2758Cross reference the 2759.Ar name 2760and 2761.Ar section 2762number of another man page. 2763.Pp 2764Examples: 2765.Dl \&.Xr mandoc 1 2766.Dl \&.Xr mandoc 1 \&; 2767.Dl \&.Xr mandoc 1 \&Ns s behaviour 2768.El 2769.Sh MACRO SYNTAX 2770The syntax of a macro depends on its classification. 2771In this section, 2772.Sq \-arg 2773refers to macro arguments, which may be followed by zero or more 2774.Sq parm 2775parameters; 2776.Sq \&Yo 2777opens the scope of a macro; and if specified, 2778.Sq \&Yc 2779closes it out. 2780.Pp 2781The 2782.Em Callable 2783column indicates that the macro may also be called by passing its name 2784as an argument to another macro. 2785For example, 2786.Sq \&.Op \&Fl O \&Ar file 2787produces 2788.Sq Op Fl O Ar file . 2789To prevent a macro call and render the macro name literally, 2790escape it by prepending a zero-width space, 2791.Sq \e& . 2792For example, 2793.Sq \&Op \e&Fl O 2794produces 2795.Sq Op \&Fl O . 2796If a macro is not callable but its name appears as an argument 2797to another macro, it is interpreted as opaque text. 2798For example, 2799.Sq \&.Fl \&Sh 2800produces 2801.Sq Fl \&Sh . 2802.Pp 2803The 2804.Em Parsed 2805column indicates whether the macro may call other macros by receiving 2806their names as arguments. 2807If a macro is not parsed but the name of another macro appears 2808as an argument, it is interpreted as opaque text. 2809.Pp 2810The 2811.Em Scope 2812column, if applicable, describes closure rules. 2813.Ss Block full-explicit 2814Multi-line scope closed by an explicit closing macro. 2815All macros contains bodies; only 2816.Ic \&Bf 2817and 2818.Pq optionally 2819.Ic \&Bl 2820contain a head. 2821.Bd -literal -offset indent 2822\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB 2823\(lBbody...\(rB 2824\&.Yc 2825.Ed 2826.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXX" -offset indent 2827.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope 2828.It Ic \&Bd Ta \&No Ta \&No Ta closed by Ic \&Ed 2829.It Ic \&Bf Ta \&No Ta \&No Ta closed by Ic \&Ef 2830.It Ic \&Bk Ta \&No Ta \&No Ta closed by Ic \&Ek 2831.It Ic \&Bl Ta \&No Ta \&No Ta closed by Ic \&El 2832.It Ic \&Ed Ta \&No Ta \&No Ta opened by Ic \&Bd 2833.It Ic \&Ef Ta \&No Ta \&No Ta opened by Ic \&Bf 2834.It Ic \&Ek Ta \&No Ta \&No Ta opened by Ic \&Bk 2835.It Ic \&El Ta \&No Ta \&No Ta opened by Ic \&Bl 2836.El 2837.Ss Block full-implicit 2838Multi-line scope closed by end-of-file or implicitly by another macro. 2839All macros have bodies; some 2840.Po 2841.Ic \&It Fl bullet , 2842.Fl hyphen , 2843.Fl dash , 2844.Fl enum , 2845.Fl item 2846.Pc 2847don't have heads; only one 2848.Po 2849.Ic \&It 2850in 2851.Ic \&Bl Fl column 2852.Pc 2853has multiple heads. 2854.Bd -literal -offset indent 2855\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB 2856\(lBbody...\(rB 2857.Ed 2858.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXXXXXXXXX" -offset indent 2859.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope 2860.It Ic \&It Ta \&No Ta Yes Ta closed by Ic \&It , Ic \&El 2861.It Ic \&Nd Ta \&No Ta \&No Ta closed by Ic \&Sh 2862.It Ic \&Nm Ta \&No Ta Yes Ta closed by Ic \&Nm , Ic \&Sh , Ic \&Ss 2863.It Ic \&Sh Ta \&No Ta Yes Ta closed by Ic \&Sh 2864.It Ic \&Ss Ta \&No Ta Yes Ta closed by Ic \&Sh , Ic \&Ss 2865.El 2866.Pp 2867Note that the 2868.Ic \&Nm 2869macro is a 2870.Sx Block full-implicit 2871macro only when invoked as the first macro 2872in a 2873.Em SYNOPSIS 2874section line, else it is 2875.Sx In-line . 2876.Ss Block partial-explicit 2877Like block full-explicit, but also with single-line scope. 2878Each has at least a body and, in limited circumstances, a head 2879.Po 2880.Ic \&Fo , 2881.Ic \&Eo 2882.Pc 2883and/or tail 2884.Pq Ic \&Ec . 2885.Bd -literal -offset indent 2886\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB 2887\(lBbody...\(rB 2888\&.Yc \(lBtail...\(rB 2889 2890\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \ 2891\(lBbody...\(rB \&Yc \(lBtail...\(rB 2892.Ed 2893.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent 2894.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope 2895.It Ic \&Ac Ta Yes Ta Yes Ta opened by Ic \&Ao 2896.It Ic \&Ao Ta Yes Ta Yes Ta closed by Ic \&Ac 2897.It Ic \&Bc Ta Yes Ta Yes Ta closed by Ic \&Bo 2898.It Ic \&Bo Ta Yes Ta Yes Ta opened by Ic \&Bc 2899.It Ic \&Brc Ta Yes Ta Yes Ta opened by Ic \&Bro 2900.It Ic \&Bro Ta Yes Ta Yes Ta closed by Ic \&Brc 2901.It Ic \&Dc Ta Yes Ta Yes Ta opened by Ic \&Do 2902.It Ic \&Do Ta Yes Ta Yes Ta closed by Ic \&Dc 2903.It Ic \&Ec Ta Yes Ta Yes Ta opened by Ic \&Eo 2904.It Ic \&Eo Ta Yes Ta Yes Ta closed by Ic \&Ec 2905.It Ic \&Fc Ta Yes Ta Yes Ta opened by Ic \&Fo 2906.It Ic \&Fo Ta \&No Ta \&No Ta closed by Ic \&Fc 2907.It Ic \&Oc Ta Yes Ta Yes Ta closed by Ic \&Oo 2908.It Ic \&Oo Ta Yes Ta Yes Ta opened by Ic \&Oc 2909.It Ic \&Pc Ta Yes Ta Yes Ta closed by Ic \&Po 2910.It Ic \&Po Ta Yes Ta Yes Ta opened by Ic \&Pc 2911.It Ic \&Qc Ta Yes Ta Yes Ta opened by Ic \&Oo 2912.It Ic \&Qo Ta Yes Ta Yes Ta closed by Ic \&Oc 2913.It Ic \&Re Ta \&No Ta \&No Ta opened by Ic \&Rs 2914.It Ic \&Rs Ta \&No Ta \&No Ta closed by Ic \&Re 2915.It Ic \&Sc Ta Yes Ta Yes Ta opened by Ic \&So 2916.It Ic \&So Ta Yes Ta Yes Ta closed by Ic \&Sc 2917.It Ic \&Xc Ta Yes Ta Yes Ta opened by Ic \&Xo 2918.It Ic \&Xo Ta Yes Ta Yes Ta closed by Ic \&Xc 2919.El 2920.Ss Block partial-implicit 2921Like block full-implicit, but with single-line scope closed by the 2922end of the line. 2923.Bd -literal -offset indent 2924\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB 2925.Ed 2926.Bl -column "MacroX" "CallableX" "ParsedX" -offset indent 2927.It Em Macro Ta Em Callable Ta Em Parsed 2928.It Ic \&Aq Ta Yes Ta Yes 2929.It Ic \&Bq Ta Yes Ta Yes 2930.It Ic \&Brq Ta Yes Ta Yes 2931.It Ic \&D1 Ta \&No Ta \&Yes 2932.It Ic \&Dl Ta \&No Ta Yes 2933.It Ic \&Dq Ta Yes Ta Yes 2934.It Ic \&En Ta Yes Ta Yes 2935.It Ic \&Op Ta Yes Ta Yes 2936.It Ic \&Pq Ta Yes Ta Yes 2937.It Ic \&Ql Ta Yes Ta Yes 2938.It Ic \&Qq Ta Yes Ta Yes 2939.It Ic \&Sq Ta Yes Ta Yes 2940.It Ic \&Vt Ta Yes Ta Yes 2941.El 2942.Pp 2943Note that the 2944.Ic \&Vt 2945macro is a 2946.Sx Block partial-implicit 2947only when invoked as the first macro 2948in a 2949.Em SYNOPSIS 2950section line, else it is 2951.Sx In-line . 2952.Ss Special block macro 2953The 2954.Ic \&Ta 2955macro can only be used below 2956.Ic \&It 2957in 2958.Ic \&Bl Fl column 2959lists. 2960It delimits blocks representing table cells; 2961these blocks have bodies, but no heads. 2962.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent 2963.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope 2964.It Ic \&Ta Ta Yes Ta Yes Ta closed by Ic \&Ta , Ic \&It 2965.El 2966.Ss In-line 2967Closed by the end of the line, fixed argument lengths, 2968and/or subsequent macros. 2969In-line macros have only text children. 2970If a number (or inequality) of arguments is 2971.Pq n , 2972then the macro accepts an arbitrary number of arguments. 2973.Bd -literal -offset indent 2974\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB \(lBres...\(rB 2975 2976\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc... 2977 2978\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN 2979.Ed 2980.Bl -column "MacroX" "CallableX" "ParsedX" "Arguments" -offset indent 2981.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Arguments 2982.It Ic \&%A Ta \&No Ta \&No Ta >0 2983.It Ic \&%B Ta \&No Ta \&No Ta >0 2984.It Ic \&%C Ta \&No Ta \&No Ta >0 2985.It Ic \&%D Ta \&No Ta \&No Ta >0 2986.It Ic \&%I Ta \&No Ta \&No Ta >0 2987.It Ic \&%J Ta \&No Ta \&No Ta >0 2988.It Ic \&%N Ta \&No Ta \&No Ta >0 2989.It Ic \&%O Ta \&No Ta \&No Ta >0 2990.It Ic \&%P Ta \&No Ta \&No Ta >0 2991.It Ic \&%Q Ta \&No Ta \&No Ta >0 2992.It Ic \&%R Ta \&No Ta \&No Ta >0 2993.It Ic \&%T Ta \&No Ta \&No Ta >0 2994.It Ic \&%U Ta \&No Ta \&No Ta >0 2995.It Ic \&%V Ta \&No Ta \&No Ta >0 2996.It Ic \&Ad Ta Yes Ta Yes Ta >0 2997.It Ic \&An Ta Yes Ta Yes Ta >0 2998.It Ic \&Ap Ta Yes Ta Yes Ta 0 2999.It Ic \&Ar Ta Yes Ta Yes Ta n 3000.It Ic \&At Ta Yes Ta Yes Ta 1 3001.It Ic \&Bsx Ta Yes Ta Yes Ta n 3002.It Ic \&Bt Ta \&No Ta \&No Ta 0 3003.It Ic \&Bx Ta Yes Ta Yes Ta n 3004.It Ic \&Cd Ta Yes Ta Yes Ta >0 3005.It Ic \&Cm Ta Yes Ta Yes Ta >0 3006.It Ic \&Db Ta \&No Ta \&No Ta 1 3007.It Ic \&Dd Ta \&No Ta \&No Ta n 3008.It Ic \&Dt Ta \&No Ta \&No Ta n 3009.It Ic \&Dv Ta Yes Ta Yes Ta >0 3010.It Ic \&Dx Ta Yes Ta Yes Ta n 3011.It Ic \&Em Ta Yes Ta Yes Ta >0 3012.It Ic \&Er Ta Yes Ta Yes Ta >0 3013.It Ic \&Es Ta Yes Ta Yes Ta 2 3014.It Ic \&Ev Ta Yes Ta Yes Ta >0 3015.It Ic \&Ex Ta \&No Ta \&No Ta n 3016.It Ic \&Fa Ta Yes Ta Yes Ta >0 3017.It Ic \&Fd Ta \&No Ta \&No Ta >0 3018.It Ic \&Fl Ta Yes Ta Yes Ta n 3019.It Ic \&Fn Ta Yes Ta Yes Ta >0 3020.It Ic \&Fr Ta Yes Ta Yes Ta >0 3021.It Ic \&Ft Ta Yes Ta Yes Ta >0 3022.It Ic \&Fx Ta Yes Ta Yes Ta n 3023.It Ic \&Hf Ta \&No Ta \&No Ta n 3024.It Ic \&Ic Ta Yes Ta Yes Ta >0 3025.It Ic \&In Ta \&No Ta \&No Ta 1 3026.It Ic \&Lb Ta \&No Ta \&No Ta 1 3027.It Ic \&Li Ta Yes Ta Yes Ta >0 3028.It Ic \&Lk Ta Yes Ta Yes Ta >0 3029.It Ic \&Lp Ta \&No Ta \&No Ta 0 3030.It Ic \&Ms Ta Yes Ta Yes Ta >0 3031.It Ic \&Mt Ta Yes Ta Yes Ta >0 3032.It Ic \&Nm Ta Yes Ta Yes Ta n 3033.It Ic \&No Ta Yes Ta Yes Ta >0 3034.It Ic \&Ns Ta Yes Ta Yes Ta 0 3035.It Ic \&Nx Ta Yes Ta Yes Ta n 3036.It Ic \&Os Ta \&No Ta \&No Ta n 3037.It Ic \&Ot Ta Yes Ta Yes Ta >0 3038.It Ic \&Ox Ta Yes Ta Yes Ta n 3039.It Ic \&Pa Ta Yes Ta Yes Ta n 3040.It Ic \&Pf Ta Yes Ta Yes Ta 1 3041.It Ic \&Pp Ta \&No Ta \&No Ta 0 3042.It Ic \&Rv Ta \&No Ta \&No Ta n 3043.It Ic \&Sm Ta \&No Ta \&No Ta <2 3044.It Ic \&St Ta \&No Ta Yes Ta 1 3045.It Ic \&Sx Ta Yes Ta Yes Ta >0 3046.It Ic \&Sy Ta Yes Ta Yes Ta >0 3047.It Ic \&Tg Ta \&No Ta \&No Ta <2 3048.It Ic \&Tn Ta Yes Ta Yes Ta >0 3049.It Ic \&Ud Ta \&No Ta \&No Ta 0 3050.It Ic \&Ux Ta Yes Ta Yes Ta n 3051.It Ic \&Va Ta Yes Ta Yes Ta n 3052.It Ic \&Vt Ta Yes Ta Yes Ta >0 3053.It Ic \&Xr Ta Yes Ta Yes Ta 2 3054.El 3055.Ss Delimiters 3056When a macro argument consists of one single input character 3057considered as a delimiter, the argument gets special handling. 3058This does not apply when delimiters appear in arguments containing 3059more than one character. 3060Consequently, to prevent special handling and just handle it 3061like any other argument, a delimiter can be escaped by prepending 3062a zero-width space 3063.Pq Sq \e& . 3064In text lines, delimiters never need escaping, but may be used 3065as normal punctuation. 3066.Pp 3067For many macros, when the leading arguments are opening delimiters, 3068these delimiters are put before the macro scope, 3069and when the trailing arguments are closing delimiters, 3070these delimiters are put after the macro scope. 3071Spacing is suppressed after opening delimiters 3072and before closing delimiters. 3073For example, 3074.Pp 3075.D1 Pf \. \&Aq "( [ word ] ) ." 3076.Pp 3077renders as: 3078.Pp 3079.D1 Aq ( [ word ] ) . 3080.Pp 3081Opening delimiters are: 3082.Pp 3083.Bl -tag -width Ds -offset indent -compact 3084.It \&( 3085left parenthesis 3086.It \&[ 3087left bracket 3088.El 3089.Pp 3090Closing delimiters are: 3091.Pp 3092.Bl -tag -width Ds -offset indent -compact 3093.It \&. 3094period 3095.It \&, 3096comma 3097.It \&: 3098colon 3099.It \&; 3100semicolon 3101.It \&) 3102right parenthesis 3103.It \&] 3104right bracket 3105.It \&? 3106question mark 3107.It \&! 3108exclamation mark 3109.El 3110.Pp 3111Note that even a period preceded by a backslash 3112.Pq Sq \e.\& 3113gets this special handling; use 3114.Sq \e&.\& 3115to prevent that. 3116.Pp 3117Many in-line macros interrupt their scope when they encounter 3118delimiters, and resume their scope when more arguments follow that 3119are not delimiters. 3120For example, 3121.Pp 3122.D1 Pf \. \&Fl "a ( b | c \e*(Ba d ) e" 3123.Pp 3124renders as: 3125.Pp 3126.D1 Fl a ( b | c \*(Ba d ) e 3127.Pp 3128This applies to both opening and closing delimiters, 3129and also to the middle delimiter, which does not suppress spacing: 3130.Pp 3131.Bl -tag -width Ds -offset indent -compact 3132.It \&| 3133vertical bar 3134.El 3135.Pp 3136As a special case, the predefined string \e*(Ba is handled and rendered 3137in the same way as a plain 3138.Sq \&| 3139character. 3140Using this predefined string is not recommended in new manuals. 3141.Pp 3142Appending a zero-width space 3143.Pq Sq \e& 3144to the end of an input line is also useful to prevent the interpretation 3145of a trailing period, exclamation or question mark as the end of a 3146sentence, for example when an abbreviation happens to occur 3147at the end of a text or macro input line. 3148.Ss Font handling 3149In 3150.Nm 3151documents, usage of semantic markup is recommended in order to have 3152proper fonts automatically selected; only when no fitting semantic markup 3153is available, consider falling back to 3154.Sx Physical markup 3155macros. 3156Whenever any 3157.Nm 3158macro switches the 3159.Xr roff 7 3160font mode, it will automatically restore the previous font when exiting 3161its scope. 3162Manually switching the font using the 3163.Xr roff 7 3164.Ql \ef 3165font escape sequences is never required. 3166.Sh COMPATIBILITY 3167This section provides an incomplete list of compatibility issues 3168between mandoc and GNU troff 3169.Pq Qq groff . 3170.Pp 3171The following problematic behaviour is found in groff: 3172.Pp 3173.Bl -dash -compact 3174.It 3175.Ic \&Pa 3176does not format its arguments when used in the FILES section under 3177certain list types. 3178.It 3179.Ic \&Ta 3180can only be called by other macros, but not at the beginning of a line. 3181.It 3182.Sq \ef 3183.Pq font face 3184and 3185.Sq \eF 3186.Pq font family face 3187.Sx Text Decoration 3188escapes behave irregularly when specified within line-macro scopes. 3189.It 3190Negative scaling units return to prior lines. 3191Instead, mandoc truncates them to zero. 3192.El 3193.Pp 3194The following features are unimplemented in mandoc: 3195.Pp 3196.Bl -dash -compact 3197.It 3198.Ic \&Bd Fl file Ar file 3199is unsupported for security reasons. 3200.It 3201.Ic \&Bd 3202.Fl filled 3203does not adjust the right margin, but is an alias for 3204.Ic \&Bd 3205.Fl ragged . 3206.It 3207.Ic \&Bd 3208.Fl literal 3209does not use a literal font, but is an alias for 3210.Ic \&Bd 3211.Fl unfilled . 3212.It 3213.Ic \&Bd 3214.Fl offset Cm center 3215and 3216.Fl offset Cm right 3217don't work. 3218Groff does not implement centered and flush-right rendering either, 3219but produces large indentations. 3220.El 3221.Sh SEE ALSO 3222.Xr man 1 , 3223.Xr mandoc 1 , 3224.Xr eqn 7 , 3225.Xr man 7 , 3226.Xr mandoc_char 7 , 3227.Xr roff 7 , 3228.Xr tbl 7 3229.Pp 3230The web page 3231.Lk https://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language" 3232provides a few tutorial-style pages for beginners, an extensive style 3233guide for advanced authors, and an alphabetic index helping to choose 3234the best macros for various kinds of content. 3235.Pp 3236The manual page 3237.Lk https://man.voidlinux.org/groff_mdoc "groff_mdoc(7)" 3238contained in the 3239.Dq groff 3240package documents exactly the same language in a somewhat different style. 3241.Sh HISTORY 3242The 3243.Nm 3244language first appeared as a troff macro package in 3245.Bx 4.4 . 3246It was later significantly updated by Werner Lemberg and Ruslan Ermilov 3247in groff-1.17. 3248The standalone implementation that is part of the 3249.Xr mandoc 1 3250utility written by Kristaps Dzonsons appeared in 3251.Ox 4.6 . 3252.Sh AUTHORS 3253The 3254.Nm 3255reference was written by 3256.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv . 3257