1MDOC.SAMPLES(7) BSD Miscellaneous Information Manual MDOC.SAMPLES(7)
2
4 mdoc.samples — tutorial sampler for writing BSD manuals with -mdoc
5
7 man mdoc.samples
8
10 A tutorial sampler for writing BSD manual pages with the -mdoc macro
11 package, a content-based and domain-based formatting package for
12 troff(1). Its predecessor, the -man(7) package, addressed page layout,
13 leaving the manipulation of fonts and other typesetting details to the
14 individual author. In -mdoc, page layout macros make up the page
15 structure domain which consists of macros for titles, section headers,
16 displays and lists. Essentially items which affect the physical position
17 of text on a formatted page. In addition to the page structure domain,
18 there are two more domains, the manual domain and the general text
19 domain. The general text domain is defined as macros which perform tasks
20 such as quoting or emphasizing pieces of text. The manual domain is
21 defined as macros that are a subset of the day to day informal language
22 used to describe commands, routines and related BSD files. Macros in the
23 manual domain handle command names, command-line arguments and options,
24 function names, function parameters, pathnames, variables, cross refer‐
25 ences to other manual pages, and so on. These domain items have value
26 for both the author and the future user of the manual page. It is hoped
27 the consistency gained across the manual set will provide easier transla‐
28 tion to future documentation tools.
29
30 Throughout the UNIX manual pages, a manual entry is simply referred to as
31 a man page, regardless of actual length and without sexist intention.
32
34 Since a tutorial document is normally read when a person desires to use
35 the material immediately, the assumption has been made that the user of
36 this document may be impatient. The material presented in the remained
37 of this document is outlined as follows:
38
39 1. TROFF IDIOSYNCRASIES
40 Macro Usage.
41 Passing Space Characters in an Argument.
42 Trailing Blank Space Characters (a warning).
43 Escaping Special Characters.
44
45 2. THE ANATOMY OF A MAN PAGE
46 A manual page template.
47
48 3. TITLE MACROS.
49
50 4. INTRODUCTION OF MANUAL AND GENERAL TEXT DOMAINS.
51 What's in a name....
52 General Syntax.
53
54 5. MANUAL DOMAIN
55 Addresses.
56 Author name.
57 Arguments.
58 Configuration Declarations (section four only).
59 Command Modifier.
60 Defined Variables.
61 Errno's (Section two only).
62 Environment Variables.
63 Function Argument.
64 Function Declaration.
65 Flags.
66 Functions (library routines).
67 Function Types.
68 Interactive Commands.
69 Names.
70 Options.
71 Pathnames.
72 Variables.
73 Cross References.
74
75 6. GENERAL TEXT DOMAIN
76 AT&T Macro.
77 BSD Macro.
78 FreeBSD Macro.
79 UNIX Macro.
80 Enclosure/Quoting Macros
81 Angle Bracket Quote/Enclosure.
82 Bracket Quotes/Enclosure.
83 Double Quote macro/Enclosure.
84 Parenthesis Quote/Enclosure.
85 Single Quotes/Enclosure.
86 Prefix Macro.
87 No-Op or Normal Text Macro.
88 No Space Macro.
89 Section Cross References.
90 References and Citations.
91 Return Values (sections two and three only)
92 Trade Names (Acronyms and Type Names).
93 Extended Arguments.
94
95 7. PAGE STRUCTURE DOMAIN
96 Section Headers.
97 Paragraphs and Line Spacing.
98 Keeps.
99 Displays.
100 Font Modes (Emphasis, Literal, and Symbolic).
101 Lists and Columns.
102
103 8. PREDEFINED STRINGS
104
105 9. DIAGNOSTICS
106
107 10. FORMATTING WITH GROFF, TROFF AND NROFF
108
109 11. BUGS
110
112 The -mdoc package attempts to simplify the process of writing a man page.
113 Theoretically, one should not have to learn the dirty details of troff(1)
114 to use -mdoc; however, there are a few limitations which are unavoidable
115 and best gotten out of the way. And, too, be forewarned, this package is
116 not fast.
117
118 Macro Usage
119 As in troff(1), a macro is called by placing a ‘.’ (dot character) at the
120 beginning of a line followed by the two character name for the macro.
121 Arguments may follow the macro separated by spaces. It is the dot char‐
122 acter at the beginning of the line which causes troff(1) to interpret the
123 next two characters as a macro name. To place a ‘.’ (dot character) at
124 the beginning of a line in some context other than a macro invocation,
125 precede the ‘.’ (dot) with the ‘\&’ escape sequence. The ‘\&’ translates
126 literally to a zero width space, and is never displayed in the output.
127
128 In general, troff(1) macros accept up to nine arguments, any extra argu‐
129 ments are ignored. Most macros in -mdoc accept nine arguments and, in
130 limited cases, arguments may be continued or extended on the next line
131 (See Extensions). A few macros handle quoted arguments (see Passing
132 Space Characters in an Argument below).
133
134 Most of the -mdoc general text domain and manual domain macros are spe‐
135 cial in that their argument lists are parsed for callable macro names.
136 This means an argument on the argument list which matches a general text
137 or manual domain macro name and is determined to be callable will be exe‐
138 cuted or called when it is processed. In this case, the argument,
139 although the name of a macro, is not preceded by a ‘.’ (dot). It is in
140 this manner that many macros are nested; for example the option macro,
141 ‘.Op’, may call the flag and argument macros, ‘Fl’ and ‘Ar’, to specify
142 an optional flag with an argument:
143
144 [-s bytes] is produced by .Op Fl s Ar bytes
145
146 To prevent a two character string from being interpreted as a macro name,
147 precede the string with the escape sequence ‘\&’:
148
149 [Fl s Ar bytes] is produced by .Op \&Fl s \&Ar bytes
150
151 Here the strings ‘Fl’ and ‘Ar’ are not interpreted as macros. Macros
152 whose argument lists are parsed for callable arguments are referred to as
153 parsed and macros which may be called from an argument list are referred
154 to as callable throughout this document and in the companion quick refer‐
155 ence manual mdoc(7). This is a technical faux pas as almost all of the
156 macros in -mdoc are parsed, but as it was cumbersome to constantly refer
157 to macros as being callable and being able to call other macros, the term
158 parsed has been used.
159
160 Passing Space Characters in an Argument
161 Sometimes it is desirable to give as one argument a string containing one
162 or more blank space characters. This may be necessary to defeat the nine
163 argument limit or to specify arguments to macros which expect particular
164 arrangement of items in the argument list. For example, the function
165 macro ‘.Fn’ expects the first argument to be the name of a function and
166 any remaining arguments to be function parameters. As ANSI C stipulates
167 the declaration of function parameters in the parenthesized parameter
168 list, each parameter is guaranteed to be at minimum a two word string.
169 For example, int foo.
170
171 There are two possible ways to pass an argument which contains an embed‐
172 ded space. Implementation note: Unfortunately, the most convenient way
173 of passing spaces in between quotes by reassigning individual arguments
174 before parsing was fairly expensive speed wise and space wise to imple‐
175 ment in all the macros for AT&T troff. It is not expensive for groff but
176 for the sake of portability, has been limited to the following macros
177 which need it the most:
178
179 Cd Configuration declaration (section 4 SYNOPSIS)
180 Bl Begin list (for the width specifier).
181 Em Emphasized text.
182 Fn Functions (sections two and four).
183 It List items.
184 Li Literal text.
185 Sy Symbolic text.
186 %B Book titles.
187 %J Journal names.
188 %O Optional notes for a reference.
189 %R Report title (in a reference).
190 %T Title of article in a book or journal.
191
192 One way of passing a string containing blank spaces is to use the hard or
193 unpaddable space character ‘\ ’, that is, a blank space preceded by the
194 escape character ‘\’. This method may be used with any macro but has the
195 side effect of interfering with the adjustment of text over the length of
196 a line. Troff sees the hard space as if it were any other printable
197 character and cannot split the string into blank or newline separated
198 pieces as one would expect. The method is useful for strings which are
199 not expected to overlap a line boundary. For example:
200
201 fetch(char *str) is created by ‘.Fn fetch char\ *str’
202
203 fetch(char *str) can also be created by ‘.Fn fetch "char *str"’
204
205 If the ‘\’ or quotes were omitted, ‘.Fn’ would see three arguments and
206 the result would be:
207
208 fetch(char, *str)
209
210 For an example of what happens when the parameter list overlaps a newline
211 boundary, see the BUGS section.
212
213 Trailing Blank Space Characters
214 Troff can be confused by blank space characters at the end of a line. It
215 is a wise preventive measure to globally remove all blank spaces from
216 <blank-space><end-of-line> character sequences. Should the need arise to
217 force a blank character at the end of a line, it may be forced with an
218 unpaddable space and the ‘\&’ escape character. For example,
219 ‘string\ \&’.
220
221 Escaping Special Characters
222 Special characters like the newline character ‘\n’, are handled by
223 replacing the ‘\’ with ‘\e’ (e.g., ‘\en’) to preserve the backslash.
224
226 The body of a man page is easily constructed from a basic template found
227 in the file /usr/share/misc/mdoc.template. Several example man pages can
228 also be found in /usr/share/examples/mdoc.
229
230 A manual page template
231 .\" The following requests are required for all man pages.
232 .Dd Month day, year
233 .Os OPERATING_SYSTEM [version/release]
234 .Dt DOCUMENT_TITLE [section number] [volume]
235 .Sh NAME
236 .Nm name
237 .Nd one line description of name
238 .Sh SYNOPSIS
239 .Sh DESCRIPTION
240 .\" The following requests should be uncommented and
241 .\" used where appropriate. This next request is
242 .\" for sections 2 and 3 function return values only.
243 .\" .Sh RETURN VALUE
244 .\" This next request is for sections 1, 6, 7 & 8 only
245 .\" .Sh ENVIRONMENT
246 .\" .Sh FILES
247 .\" .Sh EXAMPLES
248 .\" This next request is for sections 1, 6, 7 & 8 only
249 .\" (command return values (to shell) and
250 .\" fprintf/stderr type diagnostics)
251 .\" .Sh DIAGNOSTICS
252 .\" The next request is for sections 2 and 3 error
253 .\" and signal handling only.
254 .\" .Sh ERRORS
255 .\" .Sh SEE ALSO
256 .\" .Sh CONFORMING TO
257 .\" .Sh HISTORY
258 .\" .Sh AUTHORS
259 .\" .Sh BUGS
260
261 The first items in the template are the macros (.Dd, .Os, .Dt); the docu‐
262 ment date, the operating system the man page or subject source is devel‐
263 oped or modified for, and the man page title (in uppercase) along with
264 the section of the manual the page belongs in. These macros identify the
265 page, and are discussed below in TITLE MACROS.
266
267 The remaining items in the template are section headers (.Sh); of which
268 NAME, SYNOPSIS and DESCRIPTION are mandatory. The headers are discussed
269 in PAGE STRUCTURE DOMAIN, after presentation of MANUAL DOMAIN. Several
270 content macros are used to demonstrate page layout macros; reading about
271 content macros before page layout macros is recommended.
272
274 The title macros are the first portion of the page structure domain, but
275 are presented first and separate for someone who wishes to start writing
276 a man page yesterday. Three header macros designate the document title
277 or manual page title, the operating system, and the date of authorship.
278 These macros are one called once at the very beginning of the document
279 and are used to construct the headers and footers only.
280
281 .Dt DOCUMENT_TITLE section# [volume]
282 The document title is the subject of the man page and must be in
283 CAPITALS due to troff limitations. The section number may be
284 1, ..., 8, and if it is specified, the volume title may be omit‐
285 ted. A volume title may be arbitrary or one of the following:
286
287 AMD UNIX Ancestral Manual Documents
288 SMM UNIX System Manager's Manual
289 URM UNIX Reference Manual
290 PRM UNIX Programmer's Manual
291
292 The default volume labeling is URM for sections 1, 6, and 7; SMM
293 for section 8; PRM for sections 2, 3, 4, and 5.
294
295 .Os operating_system release#
296 The name of the operating system should be the common acronym,
297 for example, BSD or FreeBSD or ATT. The release should be the
298 standard release nomenclature for the system specified, for exam‐
299 ple, 4.3, 4.3+Tahoe, V.3, V.4. Unrecognized arguments are dis‐
300 played as given in the page footer. For instance, a typical
301 footer might be:
302
303 .Os 4.3BSD
304
305 or
306 .Os FreeBSD 2.2
307
308 or for a locally produced set
309
310 .Os CS Department
311
312 The Berkeley default, ‘.Os’ without an argument, has been defined
313 as BSD in the site-specific file /usr/share/tmac/mdoc/doc-common.
314 It really should default to LOCAL. Note, if the ‘.Os’ macro is
315 not present, the bottom left corner of the page will be ugly.
316
317 .Dd month day, year
318 The date should be written formally:
319
320 January 25, 1989
321
323 What's in a name...
324 The manual domain macro names are derived from the day to day informal
325 language used to describe commands, subroutines and related files.
326 Slightly different variations of this language are used to describe the
327 three different aspects of writing a man page. First, there is the
328 description of -mdoc macro request usage. Second is the description of a
329 UNIX command with -mdoc macros and third, the description of a command to
330 a user in the verbal sense; that is, discussion of a command in the text
331 of a man page.
332
333 In the first case, troff(1) macros are themselves a type of command; the
334 general syntax for a troff command is:
335
336 .Va argument1 argument2 ... argument9
337
338 The ‘.Va’ is a macro command or request, and anything following it is an
339 argument to be processed. In the second case, the description of a UNIX
340 command using the content macros is a bit more involved; a typical
341 SYNOPSIS command line might be displayed as:
342
343 filter [-flag] infile outfile
344
345 Here, filter is the command name and the bracketed string -flag is a flag
346 argument designated as optional by the option brackets. In -mdoc terms,
347 infile and outfile are called arguments. The macros which formatted the
348 above example:
349
350 .Nm filter
351 .Op Fl flag
352 .Ar infile outfile
353
354 In the third case, discussion of commands and command syntax includes
355 both examples above, but may add more detail. The arguments infile and
356 outfile from the example above might be referred to as operands or file
357 arguments. Some command-line argument lists are quite long:
358
359 make [-eiknqrstv] [-D variable] [-d flags] [-f makefile]
360 [-I directory] [-j max_jobs] [variable=value] [target ...]
361
362 Here one might talk about the command make and qualify the argument
363 makefile, as an argument to the flag, -f, or discuss the optional file
364 operand target. In the verbal context, such detail can prevent confu‐
365 sion, however the -mdoc package does not have a macro for an argument to
366 a flag. Instead the ‘Ar’ argument macro is used for an operand or file
367 argument like target as well as an argument to a flag like variable. The
368 make command line was produced from:
369
370 .Nm make
371 .Op Fl eiknqrstv
372 .Op Fl D Ar variable
373 .Op Fl d Ar flags
374 .Op Fl f Ar makefile
375 .Op Fl I Ar directory
376 .Op Fl j Ar max_jobs
377 .Op Ar variable=value
378 .Bk -words
379 .Op Ar target ...
380 .Ek
381
382 The ‘.Bk’ and ‘.Ek’ macros are explained in Keeps.
383
384 General Syntax
385 The manual domain and general text domain macros share a similar syntax
386 with a few minor deviations: ‘.Ar’, ‘.Fl’, ‘.Nm’, and ‘.Pa’ differ only
387 when called without arguments; ‘.Fn’ and ‘.Xr’ impose an order on their
388 argument lists and the ‘.Op’ and ‘.Fn’ macros have nesting limitations.
389 All content macros are capable of recognizing and properly handling punc‐
390 tuation, provided each punctuation character is separated by a leading
391 space. If a request is given:
392
393 .Li sptr, ptr),
394
395 The result is:
396
397 sptr, ptr),
398
399 The punctuation is not recognized and all is output in the literal font.
400 If the punctuation is separated by a leading white space:
401
402 .Li sptr , ptr ) ,
403
404 The result is:
405
406 sptr, ptr),
407
408 The punctuation is now recognized and is output in the default font dis‐
409 tinguishing it from the strings in literal font.
410
411 To remove the special meaning from a punctuation character escape it with
412 ‘\&’. Troff is limited as a macro language, and has difficulty when pre‐
413 sented with a string containing a member of the mathematical, logical or
414 quotation set:
415
416 {+,-,/,*,%,<,>,<=,>=,=,==,&,`,',"}
417
418 The problem is that troff may assume it is supposed to actually perform
419 the operation or evaluation suggested by the characters. To prevent the
420 accidental evaluation of these characters, escape them with ‘\&’. Typi‐
421 cal syntax is shown in the first content macro displayed below, ‘.Ad’.
422
424 Address Macro
425 The address macro identifies an address construct of the form
426 addr1[,addr2[,addr3]].
427
428 Usage: .Ad address ... [.,:;()[]?!]
429 .Ad addr1 addr1
430 .Ad addr1 . addr1.
431 .Ad addr1 , file2 addr1, file2
432 .Ad f1 , f2 , f3 : f1, f2, f3:
433 .Ad addr ) ) , addr)),
434
435 It is an error to call ‘.Ad’ without arguments. ‘.Ad’ is callable by
436 other macros and is parsed.
437
438 Author Name
439 The ‘.An’ macro is used to specify the name of the author of the item
440 being documented, or the name of the author of the actual manual page.
441 Any remaining arguments after the name information are assumed to be
442 punctuation.
443
444 Usage: .An author_name [.,:;()[]?!]
445 .An Joe Author Joe Author
446 .An Joe Author , Joe Author,
447 .An Joe Author Aq nobody@FreeBSD.ORG
448 Joe Author <nobody@FreeBSD.ORG>
449 .An Joe Author ) ) , Joe Author)),
450
451 The ‘.An’ macro is parsed and is callable. It is an error to call ‘.An’
452 without any arguments.
453
454 Argument Macro
455 The ‘.Ar’ argument macro may be used whenever a command-line argument is
456 referenced.
457
458 Usage: .Ar argument ... [.,:;()[]?!]
459 .Ar file ...
460 .Ar file1 file1
461 .Ar file1 . file1.
462 .Ar file1 file2 file1 file2
463 .Ar f1 f2 f3 : f1 f2 f3:
464 .Ar file ) ) , file)),
465
466 If ‘.Ar’ is called without arguments, ‘Ar’ is assumed. The ‘.Ar’ macro
467 is parsed and is callable.
468
469 Configuration Declaration (section four only)
470 The ‘.Cd’ macro is used to demonstrate a config(8) declaration for a
471 device interface in a section four manual. This macro accepts quoted
472 arguments (double quotes only).
473
474 device le0 at scode? produced by: ‘.Cd device le0 at scode?’.
475
476 Command Modifier
477 The command modifier is identical to the ‘.Fl’ (flag) command with the
478 exception the ‘.Cm’ macro does not assert a dash in front of every argu‐
479 ment. Traditionally flags are marked by the preceding dash, some com‐
480 mands or subsets of commands do not use them. Command modifiers may also
481 be specified in conjunction with interactive commands such as editor com‐
482 mands. See Flags.
483
484 Defined Variables
485 A variable which is defined in an include file is specified by the macro
486 ‘.Dv’.
487
488 Usage: .Dv defined_variable ... [.,:;()[]?!]
489 .Dv MAXHOSTNAMELEN MAXHOSTNAMELEN
490 .Dv TIOCGPGRP ) TIOCGPGRP)
491
492 It is an error to call ‘.Dv’ without arguments. ‘.Dv’ is parsed and is
493 callable.
494
495 Errno's (Section two only)
496 The ‘.Er’ errno macro specifies the error return value for section two
497 library routines. The second example below shows ‘.Er’ used with the
498 ‘.Bq’ general text domain macro, as it would be used in a section two
499 manual page.
500
501 Usage: .Er ERRNOTYPE ... [.,:;()[]?!]
502 .Er ENOENT ENOENT
503 .Er ENOENT ) ; ENOENT);
504 .Bq Er ENOTDIR [ENOTDIR]
505
506 It is an error to call ‘.Er’ without arguments. The ‘.Er’ macro is
507 parsed and is callable.
508
509 Environment Variables
510 The ‘.Ev’ macro specifies an environment variable.
511
512 Usage: .Ev argument ... [.,:;()[]?!]
513 .Ev DISPLAY DISPLAY
514 .Ev PATH . PATH.
515 .Ev PRINTER ) ) , PRINTER)),
516
517 It is an error to call ‘.Ev’ without arguments. The ‘.Ev’ macro is
518 parsed and is callable.
519
520 Function Argument
521 The ‘.Fa’ macro is used to refer to function arguments (parameters) out‐
522 side of the SYNOPSIS section of the manual or inside the SYNOPSIS section
523 should a parameter list be too long for the ‘.Fn’ macro and the enclosure
524 macros ‘.Fo’ and ‘.Fc’ must be used. ‘.Fa’ may also be used to refer to
525 structure members.
526
527 Usage: .Fa function_argument ... [.,:;()[]?!]
528 .Fa d_namlen ) ) , d_namlen)),
529 .Fa iov_len iov_len
530
531 It is an error to call ‘.Fa’ without arguments. ‘.Fa’ is parsed and is
532 callable.
533
534 Function Declaration
535 The ‘.Fd’ macro is used in the SYNOPSIS section with section two or three
536 functions. The ‘.Fd’ macro does not call other macros and is not
537 callable by other macros.
538
539 Usage: .Fd include_file (or defined variable)
540
541 In the SYNOPSIS section a ‘.Fd’ request causes a line break if a function
542 has already been presented and a break has not occurred. This leaves a
543 nice vertical space in between the previous function call and the decla‐
544 ration for the next function.
545
546 Flags
547 The ‘.Fl’ macro handles command-line flags. It prepends a dash, ‘-’, to
548 the flag. For interactive command flags, which are not prepended with a
549 dash, the ‘.Cm’ (command modifier) macro is identical, but without the
550 dash.
551
552 Usage: .Fl argument ... [.,:;()[]?!]
553 .Fl -
554 .Fl cfv -cfv
555 .Fl cfv . -cfv.
556 .Fl s v t -s -v -t
557 .Fl - , --,
558 .Fl xyz ) , -xyz),
559
560 The ‘.Fl’ macro without any arguments results in a dash representing
561 stdin/stdout. Note that giving ‘.Fl’ a single dash, will result in two
562 dashes. The ‘.Fl’ macro is parsed and is callable.
563
564 Functions (library routines)
565 The .Fn macro is modeled on ANSI C conventions.
566
567 Usage: .Fn [type] function [[type] parameters ... [ .,:;()[]?! ]]
568 .Fn getchar getchar()
569 .Fn strlen ) , strlen()),
570 .Fn "int align" "const * char *sptrs", int align(const * char *sptrs),
571
572 It is an error to call ‘.Fn’ without any arguments. The ‘.Fn’ macro is
573 parsed and is callable, note that any call to another macro signals the
574 end of the ‘.Fn’ call (it will close-parenthesis at that point).
575
576 For functions that have more than eight parameters (and this is rare),
577 the macros ‘.Fo’ (function open) and ‘.Fc’ (function close) may be used
578 with ‘.Fa’ (function argument) to get around the limitation. For exam‐
579 ple:
580
581 .Fo "int res_mkquery"
582 .Fa "int op"
583 .Fa "char *dname"
584 .Fa "int class"
585 .Fa "int type"
586 .Fa "char *data"
587 .Fa "int datalen"
588 .Fa "struct rrec *newrr"
589 .Fa "char *buf"
590 .Fa "int buflen"
591 .Fc
592
593 Produces:
594
595 int res_mkquery(int op, char *dname, int class, int type,
596 char *data, int datalen, struct rrec *newrr, char *buf, int buflen)
597
598 The ‘.Fo’ and ‘.Fc’ macros are parsed and are callable. In the SYNOPSIS
599 section, the function will always begin at the beginning of line. If
600 there is more than one function presented in the SYNOPSIS section and a
601 function type has not been given, a line break will occur, leaving a nice
602 vertical space between the current function name and the one prior. At
603 the moment, ‘.Fn’ does not check its word boundaries against troff line
604 lengths and may split across a newline ungracefully. This will be fixed
605 in the near future.
606
607 Function Type
608 This macro is intended for the SYNOPSIS section. It may be used anywhere
609 else in the man page without problems, but its main purpose is to present
610 the function type in kernel normal form for the SYNOPSIS of sections two
611 and three (it causes a line break allowing the function name to appear on
612 the next line).
613
614 Usage: .Ft type ... [.,:;()[]?!]
615 .Ft struct stat struct stat
616
617 The ‘.Ft’ request is not callable by other macros.
618
619 Interactive Commands
620 The ‘.Ic’ macro designates an interactive or internal command.
621
622 Usage: .Ic argument ... [.,:;()[]?!]
623 .Ic :wq :wq
624 .Ic do while {...} do while {...}
625 .Ic setenv , unsetenv setenv, unsetenv
626
627 It is an error to call ‘.Ic’ without arguments. The ‘.Ic’ macro is
628 parsed and is callable.
629
630 Name Macro
631 The ‘.Nm’ macro is used for the document title or subject name. It has
632 the peculiarity of remembering the first argument it was called with,
633 which should always be the subject name of the page. When called without
634 arguments, ‘.Nm’ regurgitates this initial name for the sole purpose of
635 making less work for the author. Note: a section two or three document
636 function name is addressed with the ‘.Nm’ in the NAME section, and with
637 ‘.Fn’ in the SYNOPSIS and remaining sections. For interactive commands,
638 such as the ‘while’ command keyword in csh(1), the ‘.Ic’ macro should be
639 used. While the ‘.Ic’ is nearly identical to ‘.Nm’, it can not recall
640 the first argument it was invoked with.
641
642 Usage: .Nm argument ... [.,:;()[]?!]
643 .Nm mdoc.sample mdoc.sample
644 .Nm \-mdoc -mdoc.
645 .Nm foo ) ) , foo)),
646 .Nm mdoc.samples
647
648 The ‘.Nm’ macro is parsed and is callable.
649
650 Options
651 The ‘.Op’ macro places option brackets around the any remaining arguments
652 on the command line, and places any trailing punctuation outside the
653 brackets. The macros ‘.Oc’ and ‘.Oo’ may be used across one or more
654 lines.
655
656 Usage: .Op options ... [.,:;()[]?!]
657 .Op []
658 .Op Fl k [-k]
659 .Op Fl k ) . [-k]).
660 .Op Fl k Ar kookfile [-k kookfile]
661 .Op Fl k Ar kookfile , [-k kookfile],
662 .Op Ar objfil Op Ar corfil [objfil [corfil]]
663 .Op Fl c Ar objfil Op Ar corfil , [-c objfil [corfil]],
664 .Op word1 word2 [word1 word2]
665
666 The ‘.Oc’ and ‘.Oo’ macros:
667
668 .Oo
669 .Op Fl k Ar kilobytes
670 .Op Fl i Ar interval
671 .Op Fl c Ar count
672 .Oc
673
674 Produce: [[-k kilobytes] [-i interval] [-c count]]
675
676 The macros ‘.Op’, ‘.Oc’ and ‘.Oo’ are parsed and are callable.
677
678 Pathnames
679 The ‘.Pa’ macro formats pathnames or filenames.
680
681 Usage: .Pa pathname [.,:;()[]?!]
682 .Pa /usr/share /usr/share
683 .Pa /tmp/fooXXXXX ) . /tmp/fooXXXXX).
684
685 The ‘.Pa’ macro is parsed and is callable.
686
687 Variables
688 Generic variable reference:
689
690 Usage: .Va variable ... [.,:;()[]?!]
691 .Va count count
692 .Va settimer, settimer,
693 .Va int *prt ) : int *prt):
694 .Va char s ] ) ) , char s])),
695
696 It is an error to call ‘.Va’ without any arguments. The ‘.Va’ macro is
697 parsed and is callable.
698
699 Manual Page Cross References
700 The ‘.Xr’ macro expects the first argument to be a manual page name, and
701 the second argument, if it exists, to be either a section page number or
702 punctuation. Any remaining arguments are assumed to be punctuation.
703
704 Usage: .Xr man_page [1,...,8] [.,:;()[]?!]
705 .Xr mdoc mdoc
706 .Xr mdoc , mdoc,
707 .Xr mdoc 7 mdoc(7)
708 .Xr mdoc 7 ) ) , mdoc(7))),
709
710 The ‘.Xr’ macro is parsed and is callable. It is an error to call ‘.Xr’
711 without any arguments.
712
714 AT&T Macro
715 Usage: .At [v6 | v7 | 32v | V.1 | V.4] ... [ .,:;()[]?! ]
716 .At AT&T UNIX
717 .At v6 . Version 6 AT&T UNIX.
718
719 The ‘.At’ macro is not parsed and not callable It accepts at most two
720 arguments.
721
722 BSD Macro
723 Usage: .Bx [Version/release] ... [.,:;()[]?!]
724 .Bx BSD
725 .Bx 4.3 . 4.3BSD.
726
727 The ‘.Bx’ macro is parsed and is callable.
728
729 FreeBSD Macro
730 Usage: .Fx Version.release ... [ .,:;()[]?! ]
731 .Fx 2.2 . FreeBSD 2.2.
732
733 The ‘.Fx’ macro is not parsed and not callable It accepts at most two
734 arguments.
735
736 UNIX Macro
737 Usage: .Ux ... [.,:;()[]?!]
738 .Ux UNIX
739
740 The ‘.Ux’ macro is parsed and is callable.
741
742 Enclosure and Quoting Macros
743 The concept of enclosure is similar to quoting. The object being to
744 enclose one or more strings between a pair of characters like quotes or
745 parentheses. The terms quoting and enclosure are used interchangeably
746 throughout this document. Most of the one line enclosure macros end in
747 small letter ‘q’ to give a hint of quoting, but there are a few irregu‐
748 larities. For each enclosure macro there is also a pair of open and
749 close macros which end in small letters ‘o’ and ‘c’ respectively. These
750 can be used across one or more lines of text and while they have nesting
751 limitations, the one line quote macros can be used inside of them.
752
753 Quote Close Open Function Result
754 .Aq .Ac .Ao Angle Bracket Enclosure <string>
755 .Bq .Bc .Bo Bracket Enclosure [string]
756 .Dq .Dc .Do Double Quote ``string''
757 .Ec .Eo Enclose String (in XX) XXstringXX
758 .Pq .Pc .Po Parenthesis Enclosure (string)
759 .Ql Quoted Literal `st' or string
760 .Qq .Qc .Qo Straight Double Quote "string"
761 .Sq .Sc .So Single Quote `string'
762
763 Except for the irregular macros noted below, all of the quoting macros
764 are parsed and callable. All handle punctuation properly, as long as it
765 is presented one character at a time and separated by spaces. The quot‐
766 ing macros examine opening and closing punctuation to determine whether
767 it comes before or after the enclosing string This makes some nesting
768 possible.
769
770 .Ec, .Eo These macros expect the first argument to be the opening and
771 closing strings respectively.
772
773 .Ql The quoted literal macro behaves differently for troff than
774 nroff. If formatted with nroff, a quoted literal is always
775 quoted. If formatted with troff, an item is quoted only if the
776 width of the item is less than three constant width characters.
777 This is to make short strings more visible where the font
778 change to literal (constant width) is less noticeable.
779
780 .Pf The prefix macro is not callable, but it is parsed:
781
782 .Pf ( Fa name2
783 becomes (name2.
784
785 The ‘.Ns’ (no space) macro performs the analogous suffix func‐
786 tion.
787
788 Examples of quoting:
789 .Aq ⟨⟩
790 .Aq Ar ctype.h ) , ⟨ctype.h⟩),
791 .Bq []
792 .Bq Em Greek , French . [Greek, French].
793 .Dq “”
794 .Dq string abc . “string abc”.
795 .Dq ´^[A-Z]´ “´^[A-Z]´”
796 .Ql man mdoc ‘man mdoc’
797 .Qq ""
798 .Qq string ) , "string"),
799 .Qq string Ns ), "string),"
800 .Sq ‘’
801 .Sq string ‘string’
802
803 For a good example of nested enclosure macros, see the ‘.Op’ option
804 macro. It was created from the same underlying enclosure macros as those
805 presented in the list above. The ‘.Xo’ and ‘.Xc’ extended argument list
806 macros were also built from the same underlying routines and are a good
807 example of -mdoc macro usage at its worst.
808
809 No-Op or Normal Text Macro
810 The macro ‘.No’ is a hack for words in a macro command line which should
811 not be formatted and follows the conventional syntax for content macros.
812
813 Space Macro
814 The ‘.Ns’ macro eliminates unwanted spaces in between macro requests. It
815 is useful for old style argument lists where there is no space between
816 the flag and argument:
817
818 .Op Fl I Ns Ar directory produces [-Idirectory]
819
820 Note: the ‘.Ns’ macro always invokes the ‘.No’ macro after eliminating
821 the space unless another macro name follows it. The macro ‘.Ns’ is
822 parsed and is callable.
823
824 Section Cross References
825 The ‘.Sx’ macro designates a reference to a section header within the
826 same document. It is parsed and is callable.
827
828 .Sx FILES FILES
829
830 References and Citations
831 The following macros make a modest attempt to handle references. At
832 best, the macros make it convenient to manually drop in a subset of refer
833 style references.
834
835 .Rs Reference Start. Causes a line break and begins collection
836 of reference information until the reference end macro is
837 read.
838 .Re Reference End. The reference is printed.
839 .%A Reference author name, one name per invocation.
840 .%B Book title.
841 .%C City/place.
842 .%D Date.
843 .%J Journal name.
844 .%N Issue number.
845 .%O Optional information.
846 .%P Page number.
847 .%R Report name.
848 .%T Title of article.
849 .%V Volume(s).
850
851 The macros beginning with ‘%’ are not callable, and are parsed only for
852 the trade name macro which returns to its caller. (And not very pre‐
853 dictably at the moment either.) The purpose is to allow trade names to
854 be pretty printed in troff/ditroff output.
855
856 Return Values
857 The ‘.Rv’ macro generates text for use in the RETURN VALUE section.
858
859 Usage: .Rv [-std function]
860
861 ‘.Rv -std atexit’ will generate the following text:
862
863 The atexit() function returns the value 0 if successful; otherwise the
864 value -1 is returned and the global variable errno is set to indicate the
865 error.
866
867 The -std option is valid only for manual page sections 2 and 3.
868
869 Trade Names (or Acronyms and Type Names)
870 The trade name macro is generally a small caps macro for all uppercase
871 words longer than two characters.
872
873 Usage: .Tn symbol ... [.,:;()[]?!]
874 .Tn DEC DEC
875 .Tn ASCII ASCII
876
877 The ‘.Tn’ macro is parsed and is callable by other macros.
878
879 Extended Arguments
880 The ‘.Xo’ and ‘.Xc’ macros allow one to extend an argument list on a
881 macro boundary. Argument lists cannot be extended within a macro which
882 expects all of its arguments on one line such as ‘.Op’.
883
884 Here is an example of ‘.Xo’ using the space mode macro to turn spacing
885 off:
886
887 .Sm off
888 .It Xo Sy I Ar operation
889 .No \en Ar count No \en
890 .Xc
891 .Sm on
892
893 Produces
894
895 Ioperation\ncount\n
896
897 Another one:
898
899 .Sm off
900 .It Cm S No / Ar old_pattern Xo
901 .No / Ar new_pattern
902 .No / Op Cm g
903 .Xc
904 .Sm on
905
906 Produces
907
908 S/old_pattern/new_pattern/[g]
909
910 Another example of ‘.Xo’ and using enclosure macros: Test the value of a
911 variable.
912
913 .It Xo
914 .Ic .ifndef
915 .Oo \&! Oc Ns Ar variable
916 .Op Ar operator variable ...
917 .Xc
918
919 Produces
920
921 .ifndef [!]variable [operator variable ...]
922
923 All of the above examples have used the ‘.Xo’ macro on the argument list
924 of the ‘.It’ (list-item) macro. The extend macros are not used very
925 often, and when they are it is usually to extend the list-item argument
926 list. Unfortunately, this is also where the extend macros are the most
927 finicky. In the first two examples, spacing was turned off; in the
928 third, spacing was desired in part of the output but not all of it. To
929 make these macros work in this situation make sure the ‘.Xo’ and ‘.Xc’
930 macros are placed as shown in the third example. If the ‘.Xo’ macro is
931 not alone on the ‘.It’ argument list, spacing will be unpredictable. The
932 ‘.Ns’ (no space macro) must not occur as the first or last macro on a
933 line in this situation. Out of 900 manual pages (about 1500 actual
934 pages) currently released with BSD only fifteen use the ‘.Xo’ macro.
935
937 Section Headers
938 The first three ‘.Sh’ section header macros list below are required in
939 every man page. The remaining section headers are recommended at the
940 discretion of the author writing the manual page. The ‘.Sh’ macro can
941 take up to nine arguments. It is parsed and but is not callable.
942
943 .Sh NAME The ‘.Sh NAME’ macro is mandatory. If not specified, the
944 headers, footers and page layout defaults will not be set
945 and things will be rather unpleasant. The NAME section
946 consists of at least three items. The first is the ‘.Nm’
947 name macro naming the subject of the man page. The second
948 is the Name Description macro, ‘.Nd’, which separates the
949 subject name from the third item, which is the description.
950 The description should be the most terse and lucid possi‐
951 ble, as the space available is small.
952
953 .Sh SYNOPSIS The SYNOPSIS section describes the typical usage of the
954 subject of a man page. The macros required are either
955 ‘.Nm’, ‘.Cd’, ‘.Fn’, (and possibly ‘.Fo’, ‘.Fc’, ‘.Fd’,
956 ‘.Ft’ macros). The function name macro ‘.Fn’ is required
957 for manual page sections 2 and 3, the command and general
958 name macro ‘.Nm’ is required for sections 1, 5, 6, 7, 8.
959 Section 4 manuals require a ‘.Nm’, ‘.Fd’ or a ‘.Cd’ config‐
960 uration device usage macro. Several other macros may be
961 necessary to produce the synopsis line as shown below:
962
963 cat [-benstuv] [-] file ...
964
965 The following macros were used:
966
967 .Nm cat
968 .Op Fl benstuv
969 .Op Fl
970 .Ar
971
972 Note: The macros ‘.Op’, ‘.Fl’, and ‘.Ar’ recognize the pipe bar character
973 ‘|’, so a command line such as:
974
975 .Op Fl a | Fl b
976
977 will not go orbital. Troff normally interprets a | as a special opera‐
978 tor. See PREDEFINED STRINGS for a usable | character in other situa‐
979 tions.
980
981 .Sh DESCRIPTION
982 In most cases the first text in the DESCRIPTION section is
983 a brief paragraph on the command, function or file, fol‐
984 lowed by a lexical list of options and respective explana‐
985 tions. To create such a list, the ‘.Bl’ begin-list, ‘.It’
986 list-item and ‘.El’ end-list macros are used (see Lists and
987 Columns below).
988
989 The following ‘.Sh’ section headers are part of the preferred manual page
990 layout and must be used appropriately to maintain consistency. They are
991 listed in the order in which they would be used.
992
993 .Sh ENVIRONMENT
994 The ENVIRONMENT section should reveal any related environment
995 variables and clues to their behavior and/or usage.
996
997 .Sh EXAMPLES
998 There are several ways to create examples. See the EXAMPLES
999 section below for details.
1000
1001 .Sh FILES
1002 Files which are used or created by the man page subject should
1003 be listed via the ‘.Pa’ macro in the FILES section.
1004
1005 .Sh SEE ALSO
1006 References to other material on the man page topic and cross
1007 references to other relevant man pages should be placed in the
1008 SEE ALSO section. Cross references are specified using the
1009 ‘.Xr’ macro. Cross references in the SEE ALSO section should
1010 be sorted by section number, and then placed in alphabetical
1011 order and comma separated. For example:
1012
1013 ls(1), ps(1), group(5), passwd(5).
1014
1015 At this time refer(1) style references are not accommodated.
1016
1017 .Sh CONFORMING TO
1018 If the command, library function or file adheres to a specific
1019 implementation such as IEEE Std 1003.2 (“POSIX.2”) or ANSI
1020 X3.159-1989 (“ANSI C89”) this should be noted here. If the
1021 command does not adhere to any standard, its history should be
1022 noted in the HISTORY section.
1023
1024 .Sh HISTORY
1025 Any command which does not adhere to any specific standards
1026 should be outlined historically in this section.
1027
1028 .Sh AUTHORS
1029 Credits, if need be, should be placed here.
1030
1031 .Sh DIAGNOSTICS
1032 Diagnostics from a command should be placed in this section.
1033
1034 .Sh ERRORS
1035 Specific error handling, especially from library functions (man
1036 page sections 2 and 3) should go here. The ‘.Er’ macro is used
1037 to specify an errno.
1038
1039 .Sh BUGS Blatant problems with the topic go here...
1040
1041 User specified ‘.Sh’ sections may be added, for example, this section was
1042 set with:
1043
1044 .Sh PAGE STRUCTURE DOMAIN
1045
1046 Paragraphs and Line Spacing.
1047 .Pp The ‘.Pp’ paragraph command may be used to specify a line space
1048 where necessary. The macro is not necessary after a ‘.Sh’ or
1049 ‘.Ss’ macro or before a ‘.Bl’ macro. (The ‘.Bl’ macro asserts a
1050 vertical distance unless the -compact flag is given).
1051
1052 Keeps
1053 The only keep that is implemented at this time is for words. The macros
1054 are ‘.Bk’ (begin-keep) and ‘.Ek’ (end-keep). The only option that ‘.Bk’
1055 accepts is -words and is useful for preventing line breaks in the middle
1056 of options. In the example for the make command-line arguments (see
1057 What's in a name), the keep prevented nroff from placing up the flag and
1058 the argument on separate lines. (Actually, the option macro used to pre‐
1059 vent this from occurring, but was dropped when the decision (religious)
1060 was made to force right justified margins in troff as options in general
1061 look atrocious when spread across a sparse line. More work needs to be
1062 done with the keep macros, a -line option needs to be added.)
1063
1064 Examples and Displays
1065 There are five types of displays, a quickie one line indented display
1066 ‘.D1’, a quickie one line literal display ‘.Dl’, and a block literal,
1067 block filled and block ragged which use the ‘.Bd’ begin-display and ‘.Ed’
1068 end-display macros.
1069
1070 .D1 (D-one) Display one line of indented text. This macro is parsed,
1071 but it is not callable.
1072
1073 -ldghfstru
1074
1075 The above was produced by: .Dl -ldghfstru.
1076
1077 .Dl (D-ell) Display one line of indented literal text. The ‘.Dl’
1078 example macro has been used throughout this file. It allows the
1079 indent (display) of one line of text. Its default font is set to
1080 constant width (literal) however it is parsed and will recognized
1081 other macros. It is not callable however.
1082
1083 % ls -ldg /usr/local/bin
1084
1085 The above was produced by .Dl % ls -ldg /usr/local/bin.
1086
1087 .Bd Begin-display. The ‘.Bd’ display must be ended with the ‘.Ed’
1088 macro. Displays may be nested within displays and lists. ‘.Bd’
1089 has the following syntax:
1090
1091 .Bd display-type [-offset offset_value] [-compact]
1092
1093 The display-type must be one of the following four types and may
1094 have an offset specifier for indentation: ‘.Bd’.
1095
1096 -ragged Display a block of text as typed, right (and left) mar‐
1097 gin edges are left ragged.
1098 -filled Display a filled (formatted) block. The block of text
1099 is formatted (the edges are filled - not left unjusti‐
1100 fied).
1101 -literal Display a literal block, useful for source code or sim‐
1102 ple tabbed or spaced text.
1103 -file file_name The filename following the -file flag is read and dis‐
1104 played. Literal mode is asserted and tabs are set at 8
1105 constant width character intervals, however any
1106 troff/-mdoc commands in file will be processed.
1107 -offset string If -offset is specified with one of the following
1108 strings, the string is interpreted to indicate the
1109 level of indentation for the forthcoming block of text:
1110
1111 left Align block on the current left margin,
1112 this is the default mode of ‘.Bd’.
1113 center Supposedly center the block. At this time
1114 unfortunately, the block merely gets left
1115 aligned about an imaginary center margin.
1116 indent Indents by one default indent value or tab.
1117 The default indent value is also used for
1118 the ‘.D1’ display so one is guaranteed the
1119 two types of displays will line up. This
1120 indent is normally set to 6n or about two
1121 thirds of an inch (six constant width char‐
1122 acters).
1123 indent-two Indents two times the default indent value.
1124 right This left aligns the block about two inches
1125 from the right side of the page. This
1126 macro needs work and perhaps may never do
1127 the right thing by troff.
1128 .Ed End-display.
1129
1130 Font Modes
1131 There are five macros for changing the appearance of the manual page
1132 text:
1133
1134 .Em Text may be stressed or emphasized with the ‘.Em’ macro. The
1135 usual font for emphasis is italic.
1136
1137 Usage: .Em argument ... [.,:;()[]?!]
1138 .Em does not does not
1139 .Em exceed 1024 . exceed 1024.
1140 .Em vide infra ) ) , vide infra)),
1141
1142 The ‘.Em’ macro is parsed and is callable. It is an error to call
1143 ‘.Em’ without arguments.
1144
1145 .Li The ‘.Li’ literal macro may be used for special characters, vari‐
1146 able constants, anything which should be displayed as it would be
1147 typed.
1148
1149 Usage: .Li argument ... [.,:;()[]?!]
1150 .Li \en \n
1151 .Li M1 M2 M3 ; M1 M2 M3;
1152 .Li cntrl-D ) , cntrl-D),
1153 .Li 1024 ... 1024 ...
1154
1155 The ‘.Li’ macro is parsed and is callable.
1156
1157 .Sy The symbolic emphasis macro is generally a boldface macro in
1158 either the symbolic sense or the traditional English usage.
1159
1160 Usage: .Sy symbol ... [.,:;()[]?!]
1161 .Sy Important Notice Important Notice
1162
1163 The ‘.Sy’ macro is parsed and
1164 is callable. Arguments to
1165 ‘.Sy’ may be quoted.
1166
1167 .Bf Begin font mode. The ‘.Bf’ font mode must be ended with the ‘.Ef’
1168 macro. Font modes may be nested within other font modes. ‘.Bf’
1169 has the following syntax:
1170
1171 .Bf font-mode
1172
1173 The font-mode must be one of the following three types: ‘.Bf’.
1174
1175 Em | -emphasis Same as if the ‘.Em’ macro was used for the
1176 entire block of text.
1177 Li | -literal Same as if the ‘.Li’ macro was used for the
1178 entire block of text.
1179 Sy | -symbolic Same as if the ‘.Sy’ macro was used for the
1180 entire block of text.
1181
1182 .Ef End font mode.
1183
1184 Tagged Lists and Columns
1185 There are several types of lists which may be initiated with the ‘.Bl’
1186 begin-list macro. Items within the list are specified with the ‘.It’
1187 item macro and each list must end with the ‘.El’ macro. Lists may be
1188 nested within themselves and within displays. Columns may be used inside
1189 of lists, but lists are unproven inside of columns.
1190
1191 In addition, several list attributes may be specified such as the width
1192 of a tag, the list offset, and compactness (blank lines between items
1193 allowed or disallowed). Most of this document has been formatted with a
1194 tag style list (-tag). For a change of pace, the list-type used to
1195 present the list-types is an over-hanging list (-ohang). This type of
1196 list is quite popular with TeX users, but might look a bit funny after
1197 having read many pages of tagged lists. The following list types are
1198 accepted by ‘.Bl’:
1199
1200 -bullet
1201 -item
1202 -enum
1203 These three are the simplest types of lists. Once the ‘.Bl’ macro has
1204 been given, items in the list are merely indicated by a line consisting
1205 solely of the ‘.It’ macro. For example, the source text for a simple
1206 enumerated list would look like:
1207
1208 .Bl -enum -compact
1209 .It
1210 Item one goes here.
1211 .It
1212 And item two here.
1213 .It
1214 Lastly item three goes here.
1215 .El
1216
1217 The results:
1218
1219 1. Item one goes here.
1220 2. And item two here.
1221 3. Lastly item three goes here.
1222
1223 A simple bullet list construction:
1224
1225 .Bl -bullet -compact
1226 .It
1227 Bullet one goes here.
1228 .It
1229 Bullet two here.
1230 .El
1231
1232 Produces:
1233 · Bullet one goes here.
1234 · Bullet two here.
1235
1236 -tag
1237 -diag
1238 -hang
1239 -ohang
1240 -inset
1241 These list-types collect arguments specified with the ‘.It’ macro and
1242 create a label which may be inset into the forthcoming text, hanged from
1243 the forthcoming text, overhanged from above and not indented or tagged.
1244 This list was constructed with the ‘Fl ohang’ list-type. The ‘.It’ macro
1245 is parsed only for the inset, hang and tag list-types and is not
1246 callable. Here is an example of inset labels:
1247
1248 Tag The tagged list (also called a tagged paragraph) is the most
1249 common type of list used in the Berkeley manuals.
1250
1251 Diag Diag lists create section four diagnostic lists and are simi‐
1252 lar to inset lists except callable macros are ignored.
1253
1254 Hang Hanged labels are a matter of taste.
1255
1256 Ohang Overhanging labels are nice when space is constrained.
1257
1258 Inset Inset labels are useful for controlling blocks of paragraphs
1259 and are valuable for converting -mdoc manuals to other formats.
1260
1261 Here is the source text which produced the above example:
1262
1263 .Bl -inset -offset indent
1264 .It Em Tag
1265 The tagged list (also called a tagged paragraph) is the
1266 most common type of list used in the Berkeley manuals.
1267 .It Em Diag
1268 Diag lists create section four diagnostic lists
1269 and are similar to inset lists except callable
1270 macros are ignored.
1271 .It Em Hang
1272 Hanged labels are a matter of taste.
1273 .It Em Ohang
1274 Overhanging labels are nice when space is constrained.
1275 .It Em Inset
1276 Inset labels are useful for controlling blocks of
1277 paragraphs and are valuable for converting
1278 .Nm -mdoc
1279 manuals to other formats.
1280 .El
1281
1282 Here is a hanged list with two items:
1283
1284 Hanged labels appear similar to tagged lists when the label is
1285 smaller than the label width.
1286
1287 Longer hanged list labels blend in to the paragraph unlike tagged
1288 paragraph labels.
1289
1290 And the unformatted text which created it:
1291
1292 .Bl -hang -offset indent
1293 .It Em Hanged
1294 labels appear similar to tagged lists when the
1295 label is smaller than the label width.
1296 .It Em Longer hanged list labels
1297 blend in to the paragraph unlike
1298 tagged paragraph labels.
1299 .El
1300
1301 The tagged list which follows uses an optional width specifier to control
1302 the width of the tag.
1303
1304 SL sleep time of the process (seconds blocked)
1305 PAGEIN number of disk I/O's resulting from references by the
1306 process to pages not loaded in core.
1307 UID numerical user-id of process owner
1308 PPID numerical ID of parent of process process priority (nonpos‐
1309 itive when in noninterruptible wait)
1310
1311 The raw text:
1312
1313 .Bl -tag -width "PAGEIN" -compact -offset indent
1314 .It SL
1315 sleep time of the process (seconds blocked)
1316 .It PAGEIN
1317 number of disk
1318 .Tn I/O Ns 's
1319 resulting from references
1320 by the process to pages not loaded in core.
1321 .It UID
1322 numerical user ID of process owner
1323 .It PPID
1324 numerical ID of parent of process process priority
1325 (nonpositive when in noninterruptible wait)
1326 .El
1327
1328 Acceptable width specifiers:
1329
1330 -width Fl sets the width to the default width for a flag. All
1331 callable macros have a default width value. The
1332 ‘.Fl’, value is presently set to ten constant width
1333 characters or about five sixth of an inch.
1334
1335 -width 24n sets the width to 24 constant width characters or
1336 about two inches. The ‘n’ is absolutely necessary
1337 for the scaling to work correctly.
1338
1339 -width ENAMETOOLONG
1340 sets width to the constant width length of the string
1341 given.
1342
1343 -width "int mkfifo"
1344 again, the width is set to the constant width of the
1345 string given.
1346
1347 If a width is not specified for the tag list type, the first time ‘.It’
1348 is invoked, an attempt is made to determine an appropriate width. If the
1349 first argument to ‘.It’ is a callable macro, the default width for that
1350 macro will be used as if the macro name had been supplied as the width.
1351 However, if another item in the list is given with a different callable
1352 macro name, a new and nested list is assumed.
1353
1355 The following strings are predefined as may be used by preceding with the
1356 troff string interpreting sequence ‘\*(xx’ where xx is the name of the
1357 defined string or as ‘\*x’ where x is the name of the string. The inter‐
1358 preting sequence may be used any where in the text.
1359
1360 String Nroff Troff
1361 <= <= ≤
1362 >= >= ≥
1363 Rq '' ”
1364 Lq `` “
1365 ua ^ ↑
1366 aa ' ´
1367 ga ` `
1368 q " "
1369 Pi pi π
1370 Ne != ≠
1371 Le <= ≤
1372 Ge >= ≥
1373 Lt < >
1374 Gt > <
1375 Pm +- ±
1376 If infinity ∞
1377 Na NaN NaN
1378 Ba | |
1379
1380 Note: The string named ‘q’ should be written as ‘\*q’ since it is only
1381 one char.
1382
1384 The debugging facilities for -mdoc are limited, but can help detect sub‐
1385 tle errors such as the collision of an argument name with an internal
1386 register or macro name. (A what?) A register is an arithmetic storage
1387 class for troff with a one or two character name. All registers internal
1388 to -mdoc for troff and ditroff are two characters and of the form
1389 <upper_case><lower_case> such as ‘Ar’, <lower_case><upper_case> as ‘aR’
1390 or <upper or lower letter><digit> as ‘C1’. And adding to the muddle,
1391 troff has its own internal registers all of which are either two lower‐
1392 case characters or a dot plus a letter or metacharacter character. In
1393 one of the introduction examples, it was shown how to prevent the inter‐
1394 pretation of a macro name with the escape sequence ‘\&’. This is suffi‐
1395 cient for the internal register names also.
1396
1397 If a nonescaped register name is given in the argument list of a request,
1398 unpredictable behavior will occur. In general, any time huge portions of
1399 text do not appear where expected in the output, or small strings such as
1400 list tags disappear, chances are there is a misunderstanding about an
1401 argument type in the argument list. Your mother never intended for you
1402 to remember this evil stuff - so here is a way to find out whether or not
1403 your arguments are valid: The ‘.Db’ (debug) macro displays the interpre‐
1404 tation of the argument list for most macros. Macros such as the ‘.Pp’
1405 (paragraph) macro do not contain debugging information. All of the
1406 callable macros do, and it is strongly advised whenever in doubt, turn on
1407 the ‘.Db’ macro.
1408
1409 Usage: .Db [on | off]
1410
1411 An example of a portion of text with the debug macro placed above and
1412 below an artificially created problem (a flag argument ‘aC’ which should
1413 be ‘\&aC’ in order to work):
1414
1415 .Db on
1416 .Op Fl aC Ar file )
1417 .Db off
1418
1419 The resulting output:
1420
1421 DEBUGGING ON
1422 DEBUG(argv) MACRO: `.Op' Line #: 2
1423 Argc: 1 Argv: `Fl' Length: 2
1424 Space: `' Class: Executable
1425 Argc: 2 Argv: `aC' Length: 2
1426 Space: `' Class: Executable
1427 Argc: 3 Argv: `Ar' Length: 2
1428 Space: `' Class: Executable
1429 Argc: 4 Argv: `file' Length: 4
1430 Space: ` ' Class: String
1431 Argc: 5 Argv: `)' Length: 1
1432 Space: ` ' Class: Closing Punctuation or suffix
1433 MACRO REQUEST: .Op Fl aC Ar file )
1434 DEBUGGING OFF
1435
1436 The first line of information tells the name of the calling macro, here
1437 ‘.Op’, and the line number it appears on. If one or more files are
1438 involved (especially if text from another file is included), the line
1439 number may be bogus. If there is only one file, it should be accurate.
1440 The second line gives the argument count, the argument (‘Fl’) and its
1441 length. If the length of an argument is two characters, the argument is
1442 tested to see if it is executable (unfortunately, any register which con‐
1443 tains a nonzero value appears executable). The third line gives the
1444 space allotted for a class, and the class type. The problem here is the
1445 argument aC should not be executable. The four types of classes are
1446 string, executable, closing punctuation and opening punctuation. The
1447 last line shows the entire argument list as it was read. In this next
1448 example, the offending ‘aC’ is escaped:
1449
1450 .Db on
1451 .Em An escaped \&aC
1452 .Db off
1453
1454 DEBUGGING ON
1455 DEBUG(fargv) MACRO: `.Em' Line #: 2
1456 Argc: 1 Argv: `An' Length: 2
1457 Space: ` ' Class: String
1458 Argc: 2 Argv: `escaped' Length: 7
1459 Space: ` ' Class: String
1460 Argc: 3 Argv: `aC' Length: 2
1461 Space: ` ' Class: String
1462 MACRO REQUEST: .Em An escaped &aC
1463 DEBUGGING OFF
1464
1465 The argument ‘\&aC’ shows up with the same length of 2 as the ‘\&’
1466 sequence produces a zero width, but a register named ‘\&aC’ was not found
1467 and the type classified as string.
1468
1469 Other diagnostics consist of usage statements and are self explanatory.
1470
1472 The -mdoc package does not need compatibility mode with groff.
1473
1474 The package inhibits page breaks, and the headers and footers which nor‐
1475 mally occur at those breaks with nroff, to make the manual more efficient
1476 for viewing on-line. At the moment, groff with -Tascii does eject the
1477 imaginary remainder of the page at end of file. The inhibiting of the
1478 page breaks makes nroff'd files unsuitable for hardcopy. There is a reg‐
1479 ister named ‘cR’ which can be set to zero in the site dependent style
1480 file /usr/src/share/tmac/doc-nroff to restore the old style behavior.
1481
1483 /usr/share/tmac/doc.tmac manual macro package
1484 /usr/share/misc/mdoc.template
1485 template for writing a man page
1486 /usr/share/examples/mdoc/* several example man pages
1487
1489 Undesirable hyphenation on the dash of a flag argument is not yet
1490 resolved, and causes occasional mishaps in the DESCRIPTION section.
1491 (line break on the hyphen).
1492
1493 Predefined strings are not declared in documentation.
1494
1495 Section 3f has not been added to the header routines.
1496
1497 ‘.Nm’ font should be changed in NAME section.
1498
1499 ‘.Fn’ needs to have a check to prevent splitting up if the line length is
1500 too short. Occasionally it separates the last parenthesis, and sometimes
1501 looks ridiculous if a line is in fill mode.
1502
1503 The method used to prevent header and footer page breaks (other than the
1504 initial header and footer) when using nroff occasionally places an
1505 unsightly partially filled line (blank) at the would be bottom of the
1506 page.
1507
1508 The list and display macros to not do any keeps and certainly should be
1509 able to.
1510
1512 man(1), troff(1), groff_mdoc(7), mdoc(7)
1513
1515 This page is part of release 4.15 of the Linux man-pages project. A
1516 description of the project, information about reporting bugs, and the
1517 latest version of this page, can be found at
1518 https://www.kernel.org/doc/man-pages/.
1519
1520BSD December 30, 1993 BSD