1MAN(7) Linux Programmer's Manual MAN(7)
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6 man - macros to format man pages
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9 groff -Tascii -man file ...
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11 groff -Tps -man file ...
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13 man [section] title
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16 This manual page explains the groff an.tmac macro package (often called
17 the man macro package). This macro package should be used by develop‐
18 ers when writing or porting man pages for Linux. It is fairly compati‐
19 ble with other versions of this macro package, so porting man pages
20 should not be a major problem (exceptions include the NET-2 BSD re‐
21 lease, which uses a totally different macro package called mdoc; see
22 mdoc(7)).
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24 Note that NET-2 BSD mdoc man pages can be used with groff simply by
25 specifying the -mdoc option instead of the -man option. Using the
26 -mandoc option is, however, recommended, since this will automatically
27 detect which macro package is in use.
28
29 For conventions that should be employed when writing man pages for the
30 Linux man-pages package, see man-pages(7).
31
32 Title line
33 The first command in a man page (after comment lines, that is, lines
34 that start with .\") should be
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36 .TH title section date source manual
37
38 For details of the arguments that should be supplied to the TH command,
39 see man-pages(7).
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41 Note that BSD mdoc-formatted pages begin with the Dd command, not the
42 TH command.
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44 Sections
45 Sections are started with .SH followed by the heading name.
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47 The only mandatory heading is NAME, which should be the first section
48 and be followed on the next line by a one-line description of the pro‐
49 gram:
50
51 .SH NAME
52 item \- description
53
54 It is extremely important that this format is followed, and that there
55 is a backslash before the single dash which follows the item name.
56 This syntax is used by the mandb(8) program to create a database of
57 short descriptions for the whatis(1) and apropos(1) commands. (See
58 lexgrog(1) for further details on the syntax of the NAME section.)
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60 For a list of other sections that might appear in a manual page, see
61 man-pages(7).
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63 Fonts
64 The commands to select the type face are:
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66 .B Bold
67
68 .BI Bold alternating with italics (especially useful for function spec‐
69 ifications)
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71 .BR Bold alternating with Roman (especially useful for referring to
72 other manual pages)
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74 .I Italics
75
76 .IB Italics alternating with bold
77
78 .IR Italics alternating with Roman
79
80 .RB Roman alternating with bold
81
82 .RI Roman alternating with italics
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84 .SB Small alternating with bold
85
86 .SM Small (useful for acronyms)
87
88 Traditionally, each command can have up to six arguments, but the GNU
89 implementation removes this limitation (you might still want to limit
90 yourself to 6 arguments for portability's sake). Arguments are delim‐
91 ited by spaces. Double quotes can be used to specify an argument which
92 contains spaces. For the macros that produce alternating type faces,
93 the arguments will be printed next to each other without intervening
94 spaces, so that the .BR command can be used to specify a word in bold
95 followed by a mark of punctuation in Roman. If no arguments are given,
96 the command is applied to the following line of text.
97
98 Other macros and strings
99 Below are other relevant macros and predefined strings. Unless noted
100 otherwise, all macros cause a break (end the current line of text).
101 Many of these macros set or use the "prevailing indent." The "prevail‐
102 ing indent" value is set by any macro with the parameter i below;
103 macros may omit i in which case the current prevailing indent will be
104 used. As a result, successive indented paragraphs can use the same in‐
105 dent without respecifying the indent value. A normal (nonindented)
106 paragraph resets the prevailing indent value to its default value (0.5
107 inches). By default, a given indent is measured in ens; try to use ens
108 or ems as units for indents, since these will automatically adjust to
109 font size changes. The other key macro definitions are:
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111 Normal paragraphs
112 .LP Same as .PP (begin a new paragraph).
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114 .P Same as .PP (begin a new paragraph).
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116 .PP Begin a new paragraph and reset prevailing indent.
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118 Relative margin indent
119 .RS i Start relative margin indent: moves the left margin i to the
120 right (if i is omitted, the prevailing indent value is used).
121 A new prevailing indent is set to 0.5 inches. As a result,
122 all following paragraph(s) will be indented until the corre‐
123 sponding .RE.
124
125 .RE End relative margin indent and restores the previous value of
126 the prevailing indent.
127
128 Indented paragraph macros
129 .HP i Begin paragraph with a hanging indent (the first line of the
130 paragraph is at the left margin of normal paragraphs, and the
131 rest of the paragraph's lines are indented).
132
133 .IP x i Indented paragraph with optional hanging tag. If the tag x is
134 omitted, the entire following paragraph is indented by i. If
135 the tag x is provided, it is hung at the left margin before
136 the following indented paragraph (this is just like .TP except
137 the tag is included with the command instead of being on the
138 following line). If the tag is too long, the text after the
139 tag will be moved down to the next line (text will not be lost
140 or garbled). For bulleted lists, use this macro with \(bu
141 (bullet) or \(em (em dash) as the tag, and for numbered lists,
142 use the number or letter followed by a period as the tag; this
143 simplifies translation to other formats.
144
145 .TP i Begin paragraph with hanging tag. The tag is given on the
146 next line, but its results are like those of the .IP command.
147
148 Hypertext link macros
149 .UR url
150 Insert a hypertext link to the URI (URL) url, with all text up
151 to the following .UE macro as the link text.
152
153 .UE [trailer]
154 Terminate the link text of the preceding .UR macro, with the op‐
155 tional trailer (if present, usually a closing parenthesis and/or
156 end-of-sentence punctuation) immediately following. For non-
157 HTML output devices (e.g., man -Tutf8), the link text is fol‐
158 lowed by the URL in angle brackets; if there is no link text,
159 the URL is printed as its own link text, surrounded by angle
160 brackets. (Angle brackets may not be available on all output
161 devices.) For the HTML output device, the link text is hyper‐
162 linked to the URL; if there is no link text, the URL is printed
163 as its own link text.
164
165 These macros have been supported since GNU Troff 1.20 (2009-01-05) and
166 Heirloom Doctools Troff since 160217 (2016-02-17).
167
168 Miscellaneous macros
169 .DT Reset tabs to default tab values (every 0.5 inches); does not
170 cause a break.
171
172 .PD d Set inter-paragraph vertical distance to d (if omitted,
173 d=0.4v); does not cause a break.
174
175 .SS t Subheading t (like .SH, but used for a subsection inside a
176 section).
177
178 Predefined strings
179 The man package has the following predefined strings:
180
181 \*R Registration Symbol: ®
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183 \*S Change to default font size
184
185 \*(Tm Trademark Symbol: ™
186
187 \*(lq Left angled double quote: “
188
189 \*(rq Right angled double quote: ”
190
191 Safe subset
192 Although technically man is a troff macro package, in reality a large
193 number of other tools process man page files that don't implement all
194 of troff's abilities. Thus, it's best to avoid some of troff's more
195 exotic abilities where possible to permit these other tools to work
196 correctly. Avoid using the various troff preprocessors (if you must,
197 go ahead and use tbl(1), but try to use the IP and TP commands instead
198 for two-column tables). Avoid using computations; most other tools
199 can't process them. Use simple commands that are easy to translate to
200 other formats. The following troff macros are believed to be safe
201 (though in many cases they will be ignored by translators): \", ., ad,
202 bp, br, ce, de, ds, el, ie, if, fi, ft, hy, ig, in, na, ne, nf, nh, ps,
203 so, sp, ti, tr.
204
205 You may also use many troff escape sequences (those sequences beginning
206 with \). When you need to include the backslash character as normal
207 text, use \e. Other sequences you may use, where x or xx are any char‐
208 acters and N is any digit, include: \', \`, \-, \., \", \%, \*x, \*(xx,
209 \(xx, \$N, \nx, \n(xx, \fx, and \f(xx. Avoid using the escape se‐
210 quences for drawing graphics.
211
212 Do not use the optional parameter for bp (break page). Use only posi‐
213 tive values for sp (vertical space). Don't define a macro (de) with
214 the same name as a macro in this or the mdoc macro package with a dif‐
215 ferent meaning; it's likely that such redefinitions will be ignored.
216 Every positive indent (in) should be paired with a matching negative
217 indent (although you should be using the RS and RE macros instead).
218 The condition test (if,ie) should only have 't' or 'n' as the condi‐
219 tion. Only translations (tr) that can be ignored should be used. Font
220 changes (ft and the \f escape sequence) should only have the values 1,
221 2, 3, 4, R, I, B, P, or CW (the ft command may also have no parame‐
222 ters).
223
224 If you use capabilities beyond these, check the results carefully on
225 several tools. Once you've confirmed that the additional capability is
226 safe, let the maintainer of this document know about the safe command
227 or sequence that should be added to this list.
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230 /usr/share/groff/[*/]tmac/an.tmac
231 /usr/man/whatis
232
234 By all means include full URLs (or URIs) in the text itself; some tools
235 such as man2html(1) can automatically turn them into hypertext links.
236 You can also use the UR and UE macros to identify links to related in‐
237 formation. If you include URLs, use the full URL (e.g.,
238 ⟨http://www.kernel.org⟩) to ensure that tools can automatically find
239 the URLs.
240
241 Tools processing these files should open the file and examine the first
242 nonwhitespace character. A period (.) or single quote (') at the be‐
243 ginning of a line indicates a troff-based file (such as man or mdoc).
244 A left angle bracket (<) indicates an SGML/XML-based file (such as HTML
245 or Docbook). Anything else suggests simple ASCII text (e.g., a "cat‐
246 man" result).
247
248 Many man pages begin with '\" followed by a space and a list of charac‐
249 ters, indicating how the page is to be preprocessed. For portability's
250 sake to non-troff translators we recommend that you avoid using any‐
251 thing other than tbl(1), and Linux can detect that automatically. How‐
252 ever, you might want to include this information so your man page can
253 be handled by other (less capable) systems. Here are the definitions
254 of the preprocessors invoked by these characters:
255
256 e [22meqn(1)
257
258 g [22mgrap(1)
259
260 p [22mpic(1)
261
262 r [22mrefer(1)
263
264 t [22mtbl(1)
265
266 v [22mvgrind(1)
267
269 Most of the macros describe formatting (e.g., font type and spacing)
270 instead of marking semantic content (e.g., this text is a reference to
271 another page), compared to formats like mdoc and DocBook (even HTML has
272 more semantic markings). This situation makes it harder to vary the
273 man format for different media, to make the formatting consistent for a
274 given media, and to automatically insert cross-references. By sticking
275 to the safe subset described above, it should be easier to automate
276 transitioning to a different reference page format in the future.
277
278 The Sun macro TX is not implemented.
279
281 apropos(1), groff(1), lexgrog(1), man(1), man2html(1), whatis(1),
282 groff_man(7), groff_www(7), man-pages(7), mdoc(7)
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285 This page is part of release 5.10 of the Linux man-pages project. A
286 description of the project, information about reporting bugs, and the
287 latest version of this page, can be found at
288 https://www.kernel.org/doc/man-pages/.
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292Linux 2020-11-01 MAN(7)