NAME | SYNOPSIS | DESCRIPTION | FILES | NOTES | BUGS | SEE ALSO | COLOPHON
MAN(7) Linux Programmer's Manual MAN(7)
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
It is extremely important that this format is followed, and that there is a
backslash before the single dash which follows the command name. This syntax
is used by the makewhatis(8) program to create a database of short command
descriptions for the whatis(1) and apropos(1) commands.
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 re-specifying
the indent value. A normal (non-indented) 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.
(Feature supported with groff only.) In order to use hypertext link macros,
it is necessary to load the www.tmac macro package. Use the request .mso
www.tmac to do this.
.URL url link trailer
Inserts a hypertext link to the URI (URL) url, with link as the text
of the link. The trailer will be printed immediately afterwards.
When generating HTML this should translate into the HTML command <A
HREF="url">link</A>trailer.
This and other related macros are new, and many tools won't do
anything with them, but since many tools (including troff) will
simply ignore undefined macros (or at worst insert their text) these
are safe to insert.
It can be useful to define your own URL macro in manual pages for the
benefit of those viewing it with a roff viewer other than groff.
That way, the URL, link text, and trailer text (if any) are still
visible.
Here's an example:
.de URL
\\$2 \(laURL: \\$1 \(ra\\$3
..
.if \n[.g] .mso www.tmac
.TH ...
(later in the page)
This software comes from the
.URL "http://www.gnu.org/" "GNU Project" " of the"
.URL "http://www.fsf.org/" "Free Software Foundation" .
In the above, if groff is being used, the www.tmac macro package's
definition of the URL macro will supersede the locally defined one.
A number of other link macros are available. See groff_www(7) for more
details.
.DT Reset tabs to default tab values (every 0.5 inches); does not cause a
break.
.PD d Set inter-paragraph vertical distance to d (if omitted, d=0.4v); does
not cause a break.
.SS t Subheading t (like .SH, but used for a subsection inside a section).
The man package has the following predefined strings:
\*R Registration Symbol: (R)
\*S Change to default font size
\*(Tm Trademark Symbol: tm
\*(lq Left angled double quote: "
\*(rq Right angled double quote: "
Although technically man is a troff macro package, in reality a large number
of other tools process man page files that don't implement all of troff's
abilities. Thus, it's best to avoid some of troff's more exotic abilities
where possible to permit these other tools to work correctly. Avoid using the
various troff preprocessors (if you must, go ahead and use tbl(1), but try to
use the IP and TP commands instead for two-column tables). Avoid using
computations; most other tools can't process them. Use simple commands that
are easy to translate to other formats. The following troff macros are
believed to be safe (though in many cases they will be ignored by
translators): \", ., ad, bp, br, ce, de, ds, el, ie, if, fi, ft, hy, ig, in,
na, ne, nf, nh, ps, so, sp, ti, tr.
You may also use many troff escape sequences (those sequences beginning with
\). 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 new URL macro to identify links to related information. If you
include URLs, use the full URL (e.g., <http://www.kernelnotes.org>) to ensure
that tools can automatically find the URLs.
Tools processing these files should open the file and examine the first non-
whitespace 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), man(1), man2html(1), whatis(1), groff_man(7),
groff_www(7), man-pages(7), mdoc(7), mdoc.samples(7)
This page is part of release 3.23 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
Linux 2007-05-30 MAN(7)