man - macros to format man pages
groff -Tascii -man file ...
groff -Tps -man file ...
man [
section]
title
This manual page explains the
groff an.tmac macro package (often called
the
man macro package). This macro package should be used by developers
when writing or porting man pages for Linux. It is fairly compatible with
other versions of this macro package, so porting man pages should not be a
major problem (exceptions include the NET-2 BSD release, which uses a totally
different macro package called mdoc; see
mdoc(7)).
Note that NET-2 BSD mdoc man pages can be used with
groff simply by
specifying the
-mdoc option instead of the
-man option. Using
the
-mandoc option is, however, recommended, since this will
automatically detect which macro package is in use.
For conventions that should be employed when writing man pages for the Linux
man-pages package, see
man-pages(7).
The first command in a man page (after comment lines, that is, lines that start
with
.\") should be
.TH title section date source manual
For details of the arguments that should be supplied to the
TH command,
see
man-pages(7).
Note that BSD mdoc-formatted pages begin with the
Dd command, not the
TH command.
Sections are started with
.SH followed by the heading name.
The only mandatory heading is NAME, which should be the first section and be
followed on the next line by a one-line description of the program:
.SH NAME
item \- description
It is extremely important that this format is followed, and that there is a
backslash before the single dash which follows the item name. This syntax is
used by the
mandb(8) program to create a database of short descriptions
for the
whatis(1) and
apropos(1) commands. (See
lexgrog(1) for further details on the syntax of the NAME section.)
For a list of other sections that might appear in a manual page, see
man-pages(7).
The commands to select the type face are:
- .B
- Bold
- .BI
- Bold alternating with italics (especially useful for function
specifications)
- .BR
- Bold alternating with Roman (especially useful for referring to other
manual pages)
- .I
- Italics
- .IB
- Italics alternating with bold
- .IR
- Italics alternating with Roman
- .RB
- Roman alternating with bold
- .RI
- Roman alternating with italics
- .SB
- Small alternating with bold
- .SM
- Small (useful for acronyms)
Traditionally, each command can have up to six arguments, but the GNU
implementation removes this limitation (you might still want to limit yourself
to 6 arguments for portability's sake). Arguments are delimited by spaces.
Double quotes can be used to specify an argument which contains spaces. All of
the arguments will be printed next to each other without intervening spaces,
so that the
.BR command can be used to specify a word in bold followed
by a mark of punctuation in Roman. If no arguments are given, the command is
applied to the following line of text.
Below are other relevant macros and predefined strings. Unless noted otherwise,
all macros cause a break (end the current line of text). Many of these macros
set or use the "prevailing indent." The "prevailing
indent" value is set by any macro with the parameter
i below;
macros may omit
i in which case the current prevailing indent will be
used. As a result, successive indented paragraphs can use the same indent
without respecifying the indent value. A normal (nonindented) paragraph resets
the prevailing indent value to its default value (0.5 inches). By default, a
given indent is measured in ens; try to use ens or ems as units for indents,
since these will automatically adjust to font size changes. The other key
macro definitions are:
- .LP
- Same as .PP (begin a new paragraph).
- .P
- Same as .PP (begin a new paragraph).
- .PP
- Begin a new paragraph and reset prevailing indent.
- .RS i
- Start relative margin indent: moves the left margin i to the right
(if i is omitted, the prevailing indent value is used). A new
prevailing indent is set to 0.5 inches. As a result, all following
paragraph(s) will be indented until the corresponding .RE.
- .RE
- End relative margin indent and restores the previous value of the
prevailing indent.
- .HP i
- Begin paragraph with a hanging indent (the first line of the paragraph is
at the left margin of normal paragraphs, and the rest of the paragraph's
lines are indented).
- .IP x i
- Indented paragraph with optional hanging tag. If the tag x is
omitted, the entire following paragraph is indented by i. If the
tag x is provided, it is hung at the left margin before the
following indented paragraph (this is just like .TP except the tag
is included with the command instead of being on the following line). If
the tag is too long, the text after the tag will be moved down to the next
line (text will not be lost or garbled). For bulleted lists, use this
macro with \(bu (bullet) or \(em (em dash) as the tag, and for numbered
lists, use the number or letter followed by a period as the tag; this
simplifies translation to other formats.
- .TP i
- Begin paragraph with hanging tag. The tag is given on the next line, but
its results are like those of the .IP command.
- .UR url
- Insert a hypertext link to the URI (URL) url, with all text up to
the following .UE macro as the link text.
- .UE [trailer]
- Terminate the link text of the preceding .UR macro, with the
optional trailer (if present, usually a closing parenthesis and/or
end-of-sentence punctuation) immediately following. For non-HTML output
devices (e.g., man -Tutf8), the link text is followed by the URL in
angle brackets; if there is no link text, the URL is printed as its own
link text, surrounded by angle brackets. (Angle brackets may not be
available on all output devices.) For the HTML output device, the link
text is hyperlinked to the URL; if there is no link text, the URL is
printed as its own link text.
These macros have been supported since GNU Troff 1.20 (2009-01-05) and Heirloom
Doctools Troff since 160217 (2016-02-17).
- .DT
- Reset tabs to default tab values (every 0.5 inches); does not cause a
break.
- .PD d
- Set inter-paragraph vertical distance to d (if omitted, d=0.4v); does not
cause a break.
- .SS t
- Subheading t (like .SH, but used for a subsection inside a
section).
The
man package has the following predefined strings:
- \*R
- Registration Symbol: ®
- \*S
- Change to default font size
- \*(Tm
- Trademark Symbol: (Tm)
- \*(lq
- Left angled double quote: “
- \*(rq
- Right angled double quote: ”
Although technically
man is a troff macro package, in reality a large
number of other tools process man page files that don't implement all of
troff's abilities. Thus, it's best to avoid some of troff's more exotic
abilities where possible to permit these other tools to work correctly. Avoid
using the various troff preprocessors (if you must, go ahead and use
tbl(1), but try to use the
IP and
TP commands instead for
two-column tables). Avoid using computations; most other tools can't process
them. Use simple commands that are easy to translate to other formats. The
following troff macros are believed to be safe (though in many cases they will
be ignored by translators):
\",
.,
ad,
bp,
br,
ce,
de,
ds,
el,
ie,
if,
fi,
ft,
hy,
ig,
in,
na,
ne,
nf,
nh,
ps,
so,
sp,
ti,
tr.
You may also use many troff escape sequences (those sequences beginning with \).
When you need to include the backslash character as normal text, use \e. Other
sequences you may use, where x or xx are any characters and N is any digit,
include:
\',
\`,
\-,
\.,
\",
\%,
\*x,
\*(xx,
\(xx,
\$N,
\nx,
\n(xx,
\fx, and
\f(xx. Avoid using the escape sequences
for drawing graphics.
Do not use the optional parameter for
bp (break page). Use only positive
values for
sp (vertical space). Don't define a macro (
de) with
the same name as a macro in this or the mdoc macro package with a different
meaning; it's likely that such redefinitions will be ignored. Every positive
indent (
in) should be paired with a matching negative indent (although
you should be using the
RS and
RE macros instead). The condition
test (
if,ie) should only have 't' or 'n' as the condition. Only
translations (
tr) that can be ignored should be used. Font changes
(
ft and the
\f escape sequence) should only have the values 1,
2, 3, 4, R, I, B, P, or CW (the ft command may also have no parameters).
If you use capabilities beyond these, check the results carefully on several
tools. Once you've confirmed that the additional capability is safe, let the
maintainer of this document know about the safe command or sequence that
should be added to this list.
/usr/share/groff/[*/]
tmac/an.tmac
/usr/man/whatis
By all means include full URLs (or URIs) in the text itself; some tools such as
man2html(1) can automatically turn them into hypertext links. You can
also use the
UR and
UE macros to identify links to related
information. If you include URLs, use the full URL (e.g.,
http://www.kernel.org
to ensure that tools can automatically find the URLs.
Tools processing these files should open the file and examine the first
nonwhitespace character. A period (.) or single quote (') at the beginning of
a line indicates a troff-based file (such as man or mdoc). A left angle
bracket (<) indicates an SGML/XML-based file (such as HTML or Docbook).
Anything else suggests simple ASCII text (e.g., a "catman" result).
Many man pages begin with
'\" followed by a space and a list of
characters, indicating how the page is to be preprocessed. For portability's
sake to non-troff translators we recommend that you avoid using anything other
than
tbl(1), and Linux can detect that automatically. However, you
might want to include this information so your man page can be handled by
other (less capable) systems. Here are the definitions of the preprocessors
invoked by these characters:
- e
- eqn(1)
- g
- grap(1)
- p
- pic(1)
- r
- refer(1)
- t
- tbl(1)
- v
- vgrind(1)
Most of the macros describe formatting (e.g., font type and spacing) instead of
marking semantic content (e.g., this text is a reference to another page),
compared to formats like mdoc and DocBook (even HTML has more semantic
markings). This situation makes it harder to vary the
man format for
different media, to make the formatting consistent for a given media, and to
automatically insert cross-references. By sticking to the safe subset
described above, it should be easier to automate transitioning to a different
reference page format in the future.
The Sun macro
TX is not implemented.
apropos(1),
groff(1),
lexgrog(1),
man(1),
man2html(1),
whatis(1),
groff_man(7),
groff_www(7),
man-pages(7),
mdoc(7)