Ubuntu Manpage: groff_man - GNU roff macro package for formatting man pages

NAME

       groff_man - GNU roff macro package for formatting man pages

SYNOPSIS

       groff -man [option ...] [input-file ...]
       groff -m man [option ...] [input-file ...]

DESCRIPTION

The man macro package for groff is used to produce manual pages (“man pages”) like the one
you are reading. GNU roff's implementation was written by James Clark.

This document presents the macros thematically to aid learners; for those needing only a
quick reference, the following table lists them alphabetically, with cross-references to
appropriate subsections below.

Macro Meaning Subsection
───────────────────────────────────────────────────────────────────
.B Bold Font style macros
.BI Bold, italic alternating Font style macros
.BR Bold, roman alternating Font style macros
.EE Example end Document structure macros
.EX Example begin Document structure macros
.I Italic Font style macros
.IB Italic, bold alternating Font style macros
.IP Indented paragraph Paragraph macros
.IR Italic, roman alternating Font style macros
.LP (Left) paragraph Paragraph macros
.ME Mail-to end Hyperlink and email macros
.MT Mail-to start Hyperlink and email macros
.OP (Command-line) option Command synopsis macros
.P Paragraph Paragraph macros
.PP Paragraph Paragraph macros
.RB Roman, bold alternating Font style macros
.RE Relative-indent end Document structure macros
.RI Roman, italic alternating Font style macros
.RS Relative-indent start Document structure macros
.SB Small bold Font style macros
.SH Section heading Document structure macros
.SM Small Font style macros
.SS Subection heading Document structure macros
.SY Synopsis start Command synopsis macros
.TH Title heading Document structure macros
.TP Tagged paragraph Paragraph macros
.TQ Tagged paragraph continuation Paragraph macros
.UE URL end Hyperlink and email macros
.UR URL start Hyperlink and email macros
.YS Synopsis end Command synopsis macros

Macros whose use we discourage (.AT, .BT, .DT, .HP, .PD, .PT, and .UC) are described in
subsection “Deprecated features”, below.

Macro reference preliminaries
Each macro is described in a tagged paragraph. Closely related macros, such as .EX and
.EE, are grouped together.

Optional macro arguments are indicated by surrounding them with square brackets. If a
macro accepts multiple arguments, arguments containing whitespace must be double-quoted
("one two"), to be interpreted correctly. Most macro arguments are strings that will be
output as text; exceptions are noted.

Bear in mind that groff is fundamentally a programming system for typesetting.
Consequently, the verb “to set” is frequently used below in the sense “to typeset”.

Document structure macros
The highest level of organization of a man page is determined by this group of macros.
.TH (title heading) identifies the document as a man page and defines information enabling
its indexing by mandb(8) or a similar tool. Sections (.SH), one of which is mandatory and
many of which are standardized, facilitate quick location of relevant material by the
reader and aid the man page writer to discuss all essential aspects of the topic.
Subsections (.SS) are optional and permit sections that grow long to develop in a
controlled way. Many technical discussions require examples; lengthy ones, especially
those reflecting multiple lines of input to or output from the system, are usefully
bracketed by .EX and .EE. When none of the foregoing meets a structural demand, a section
of the discussion can be manually indented within .RS and .RE macros.

.TH title section [footer-middle] [footer-outside] [header-middle]
Define the title of the man page as title and the section as section. See man(1)
for details on the section numbers and suffixes applicable to your system. title
and section are positioned together at the left and right in the header line (with
section in parentheses immediately appended to title). footer-middle is centered
in the footer line. footer-outside is positioned at the left in the footer line
(or at the left on even pages and at the right on odd pages if double-sided
printing is active). header-middle is centered in the header line. If section is
a simple integer between 1 and 9 (inclusive), or is exactly “3p”, there is no need
to specify header-middle; the macro package will supply text for it.

For HTML output, headers and footers are completely suppressed.

Additionally, this macro starts a new page; the page number is reset to 1 (unless
the -rC1 option is given on the command line). This feature is intended only for
formatting multiple man pages.

A man page should contain exactly one .TH call at or near the beginning of the
file, prior to any other macro calls.

By convention, footer-middle is the most recent modification date of the man page
source document, and footer-outside is the name and version or release of the
project providing it.

.SH [heading-text]
Set heading-text as a section heading flush left. The text following .SH up to the
end of the line, or the text on the next input line if .SH is given no arguments,
is set in bold (or the font specified by the string register HF) slightly larger
than the base font size. Additionally, the left margin and indentation affecting
subsequent text are reset to their default values. Text on input lines after
heading-text is set as a normal paragraph (.PP).

The content of heading-text and ordering of sections has been standardized by
common practice, as has much of the layout of material within sections. For
example, a section called “Name” or “NAME” must exist, must be the first section
after the .TH call, and must contain only a line of the form
page-topic[, ...] \- summary-description
for a man page to be properly indexed. See man(7) for the conventions prevailing
on your system.

.SS [subheading-text]
Set subheading-text as a subsection heading indented (by default) partway between a
section heading and a normally-indented paragraph (.PP). The text following .SS up
to the end of the line, or the text on the next input line if .SS is given no
arguments, is set in bold (or the font specified by the string register HF) at the
base font size. Additionally, the left margin and indentation affecting subsequent
text are reset to their default values. Text on input lines after subheading-text
is set as a normal paragraph (.PP).

.EX
.EE Begin and end example. After .EX, filling and hyphenation are disabled and a
constant-width (monospaced) font is selected. Calling .EE enables filling and
restores the previous hyphenation setting and font.

Example regions are useful for formatting code, shell sessions, and text file
contents.

These macros are defined on many (but not all) legacy Unix systems running classic
troff. To be certain your page will be portable to those systems, copy their
definitions from the an-ext.tmac file of a groff installation.

.RS [indent]
Move the left margin to the right by the value indent, if specified, and by a
default amount otherwise; see subsection “Horizontal and vertical spacing” below.
Calls to .RS can be nested; each call increments by 1 the indentation level used by
.RE. The indentation level prior to any .RS calls is 1.

.RE [level]
Move the left margin back to that corresponding to indentation level level. If no
argument is given, move the left margin one level back.

Paragraph macros
A typical paragraph (.PP) is set at the current left margin, which by default is indented
from the left margin of the output device. In man pages and other technical literature,
definition lists are frequently encountered; these can be set as “tagged paragraphs” (.TP
and .TQ), which have one or more leading tags followed by a paragraph that has an
additional left indent. The indented paragraph (.IP) macro is useful to continue the
indented content of a narrative started with .TP, or to present an itemized or ordered
list.

.LP
.PP
.P Begin a new paragraph; these macros are synonymous. They break the output line at
the current position, followed by a vertical space downward by a default amount
(which can be changed by the deprecated .PD macro). The font size and style are
reset to defaults; see subsection “Font style macros” below. Finally, the left
margin and indentation are reset to default values.

.TP [indent]
Set a tagged, indented paragraph. The input line following this macro, known as
the tag, is printed at the current left margin. Subsequent text is indented by
indent, if specified, and by a default amount otherwise; see subsection “Horizontal
and vertical spacing” below.

If the tag is not as wide as the indentation, the paragraph starts on the same line
as the tag, at the applicable indentation, and continues on the following lines.
Otherwise, the descriptive part of the paragraph begins on the line following the
tag, entirely indented. The line containing the tag can include a macro call, for
instance to set the tag in bold with .B.

.TP was used to write the first paragraph of this description of .TP, and .IP the
subsequent ones.

.TQ Set an additional tag for a paragraph tagged with .TP. The pending output line is
broken. The tag on the input line following this macro and subsequent lines are
handled as with .TP.

This macro is not defined on legacy Unix systems running classic troff. To be
certain your page will be portable to those systems, copy its definition from the
an-ext.tmac file of a groff installation.

The descriptions of .LP, .PP, and .P above were written using .TP and .TQ.

.IP [tag] [indent]
Set an indented paragraph with an optional tag. The tag and indent arguments, if
present, are handled as with .TP, with the exception that the tag argument to .IP
cannot include a macro call.

Two convenient use cases for .IP are

(1) to start a new paragraph with the same indentation as the previous .IP
or .TP paragraph, if no indent argument is given; and

(2) to set a paragraph with a short tag that is not semantically important,
such as a bullet (•)—obtained with the ‘\(bu’ character escape—or list
enumerator, as seen in this very paragraph.

Command synopsis macros
Command synopses are a staple of section 1 and 8 man pages. These macros aid you to
construct one that has the classical Unix appearance. Furthermore, some tools are able to
interpret these macros semantically and treat them appropriately for localization and/or
presentation. A command synopsis is wrapped in .SY/.YS calls, with command-line options
of some formats indicated by .OP.

These macros are not defined on legacy Unix systems running classic troff. To be certain
your page will be portable to those systems, copy their definitions from the an-ext.tmac
file of a groff installation.

.SY command
Begin synopsis. Hyphenation is turned off. The command argument is set in bold.
The output line is filled as normal, but if a break is required, subsequent output
lines are indented by the width of command plus a space.

.OP option-name [option-argument]
Indicate an optional command parameter called option-name, which is set in bold.
If the option takes an argument, specify option-argument using a noun,
abbreviation, or hyphenated noun phrase. If present, option-argument is preceded
by a space and set in italics. Square brackets (in roman) surround both arguments.

.YS End synopsis. Restore indentation and hyphenation to previous values.

Multiple .SY/.YS blocks can be specified, for instance to distinguish differing modes of
operation of a complex command like tar(1); each will be separated by a paragraph space.

.SY can also be repeated multiple times before a closing .YS, which is useful to indicate
synonymous ways of invoking a particular mode of operation.

For example,

.SY groff
.OP \-abcegiklpstzCEGNRSUVXZ
.OP \-d cs
.OP \-f fam
.OP \-F dir
.OP \-I dir
.OP \-K arg
.OP \-L arg
.OP \-m name
.OP \-M dir
.OP \-n num
.OP \-o list
.OP \-P arg
.OP \-r cn
.OP \-T dev
.OP \-w name
.OP \-W name
.RI [ file
\&.\|.\|.\&]
.YS
.
.SY groff
.B \-h
.SY groff
.B \-\-help
.YS

produces the following output.

groff [-abcegiklpstzCEGNRSUVXZ] [-d cs] [-f fam] [-F dir] [-I dir] [-K arg]
[-L arg] [-m name] [-M dir] [-n num] [-o list] [-P arg] [-r cn] [-T dev]
[-w name] [-W name] [file ...]

groff -h
groff --help

Several features of the above example are of note.

• The empty request (.), which does nothing, is used for vertical spacing in the
input file for readability by the document maintainer. Do not put empty lines in a
roff source document.

• The command and option names are presented in bold to cue the user that they should
be input literally.

• Option dashes are specified with the ‘\-’ escape sequence; this is an important
practice to make them clearly visible and to facilitate cut-and-paste from the
rendered man page to a shell prompt or text file.

• Option arguments and command operands are presented in italics (underlined on some
output devices, such as terminals and emulators), to cue the user that they must be
replaced with appropriate text.

• Symbols that are neither to be typed literally nor simply replaced appear in the
roman style; brackets surround optional arguments, and an ellipsis indicates that
the previous syntactical element may be repeated arbitrarily.

Some man pages use a brace-and-pipe notation such as “{--diff|--compare}” to
indicate that one and only one of the ‘|’-separated items within the braces must be
input. If this braced construct is furthermore surrounded by square brackets, it
means that at most one of the items is accepted.

Authors of man pages should note the use of the zero-width space escape sequence
‘\&’ on both sides of the ellipsis; this is a good practice to avoid surprises in
the event the ellipsis gets refilled in your text editor. See “Portability”,
below. The morbidly curious may consult groff(7) regarding the narrow-space escape
sequence ‘\|’.

Hyperlink and email macros
Email addresses are bracketed with .MT/.ME and URL hyperlinks with .UR/.UE.

.MT address
.ME [punctuation]
Identify address as an RFC 6068 addr-spec for a “mailto:” URI with the text between
the two macro calls as the link text. A punctuation argument to .ME is placed at
the end of the link text without intervening space. Note that address may not be
visible in the output text, particularly if the man page is being viewed as HTML.
On a device that is not a browser, address is set in angle brackets after the link
text and before punctuation.

When rendered by groff to a TTY or PostScript output device,

Contact
.MT fred.foonly@\:fubar.net
Fred Foonly
.ME
for more information.

displays as: “Contact Fred Foonly ⟨fred.foonly@fubar.net⟩ for more information.”.

The use of ‘\:’ to insert hyphenless discretionary breaks is a groff extension and
can be omitted.

.UR URL
.UE [punctuation]
Identify URL as an RFC 3986 URI hyperlink with the text between the two macro calls
as the link text. A punctuation argument to .UE is placed at the end of the link
text without intervening space. Note that URL may not be visible in the output
text, particularly if the man page is being viewed as HTML. On a device that is
not a browser, URL is set in angle brackets after the link text and before
punctuation.

When rendered by groff to a TTY or PostScript output device,

The GNU Project of the Free Software Foundation hosts the
.UR https://\:www.gnu.org/\:software/\:groff/
Groff home page
.UE .

displays as: “The GNU Project of the Free Software Foundation hosts the Groff home
page ⟨https://www.gnu.org/software/groff/⟩.”.

The use of ‘\:’ to insert hyphenless discretionary breaks is a groff extension and
can be omitted.

Font style macros
The man macro package is limited in its font styling options, offering only bold (.B),
italic (.I), and roman (the default). Italic text is usually set underscored instead on
terminals and other classical nroff-style output devices. The .SM and .SB macros set text
in roman or bold, respectively, at a smaller point size; these differ visually from
regular-sized roman or bold text only on troff-style output devices. The foregoing macros
cause word breaks before and after their arguments, but it is often necessary to set text
in different styles without intervening whitespace. The macros .BI, .BR, .IB, .IR, .RB,
and .RI, where ‘B’, ‘I’, and ‘R’ indicate bold, italic, and roman, respectively, set their
odd- and even-numbered arguments in alternating styles, with no whitespace separating
them.

Because font styles are presentational rather than semantic, conflicting traditions have
arisen regarding which font styles should be used to mark file or path names, environment
variables, in-line literals, and even man page cross-references.

The default font size and family (for troff output devices) is 10-point Times. The
default style is roman.

.B [text]
Set text in bold. If the macro is given no arguments, the text of the next input
line is set in bold.

Use bold for literal portions of syntax synopses, for command-line options in
running text, and for literals that are major topics of the subject under
discussion; for example, this page uses bold for macro and register names. In
.EX/.EE examples of interactive I/O (such as a shell session), set only the user-
typed input in bold.

.I [text]
Set text in italics. If the macro is given no arguments, the text of the next
input line is set in italics.

Use italics for file and path names, for environment variables, for enumeration or
preprocessor constants in C, for variable (user-determined) portions of syntax
synopses, for the first occurrence only of a technical concept being introduced,
for names of works of software (including commands and functions, but excluding
names of operating systems or their kernels), and anywhere a parameter requiring
replacement by the user is encountered. An exception involves variable text in a
context that is already marked up in italics, such as file or path names with
variable components; in such cases, follow the convention of mathematical
typography: set the file or path name in italics as usual (see .IR below), but use
roman for the variable part, and italics again in running roman text when referring
to the variable material.

.SM [text]
Set text one point size smaller than the default size. If the macro is given no
arguments, the text of the next input line is set smaller.

Note: nroff-style output devices, such as terminals, will render text at the normal
font size instead. Do not rely upon .SM to communicate semantic information
distinct from using roman style at the normal size; it will be hidden from readers
using such devices.

.SB [text]
Set text in bold, one point size smaller than the default size. If the macro is
given no arguments, the text of the next input line is set smaller and in bold.

Note: nroff-style output devices, such as terminals, will render text in bold at
the normal font size instead. Do not rely upon .SB to communicate semantic
information distinct from using bold style at the normal size; it will be hidden
from readers using such devices.

Note what is not prescribed for setting in bold or italics above: elements of “synopsis
language” such as ellipses and brackets around options; proper names and adjectives;
titles of anything other than works of literature or software; identifiers for standards
documents or technical reports such as CSTR #54, RFC 1918, Unicode 11.0, or POSIX.1-2017;
acronyms; and occurrences after the first of a technical term or piece of jargon. Again,
the names of operating systems and their kernels are, by practically universal convention,
set in roman.

Be frugal with the use of italics for emphasis, and particularly with the use of bold.
Brief runs of literal text, such as references to individual characters or short strings,
including section and subsection headings of man pages, are suitable objects for
quotation; see the ‘\(lq’, ‘\(rq’, ‘\(oq’, and ‘\(cq’ escapes in subsection “Portability”
below.

Unlike the above font style macros, the font alternation macros below accept only
arguments on the same line as the macro call. If whitespace is required within one of the
arguments, first consider whether the same result could be achieved with as much clarity
by using the single-style macros on separate input lines. When it cannot, double-quote an
argument with one or more embedded space characters. Setting all three different styles
within one whitespace-delimited word presents challenges; it is possible with the ‘\c’
and/or ‘\f’ escapes, but see subsection “Portability” below for caveats.

.BI bold-text italic-text ...
Set each argument in bold and italics, alternately.

.BI \-r name = n

.BR bold-text roman-text ...
Set each argument in bold and roman, alternately.

Any such change becomes effective with the first use of
.BR .NH ,
.I after
the new alias is defined.

.IB italic-text bold-text ...
Set each argument in italics and bold, alternately.

All macro package files must be named
.IB name .tmac
to fully use the
.I tmac
mechanism.

.IR italic-text roman-text ...
Set each argument in italics and roman, alternately.

This is the first command of the
.IR prologue .

.RB roman-text bold-text ...
Set each argument in roman and bold, alternately.

Also, the statement
.RB \(oq "delim on" \(cq
is not handled specially.

.RI roman-text italic-text ...
Set each argument in roman and italics, alternately.

.RI [ file
\&.\|.\|.\&]

Horizontal and vertical spacing
The indent argument accepted by .RS, .IP, .TP, and the deprecated .HP is a number plus an
optional scaling indicator. If no scaling indicator is given, the man package assumes
‘n’; that is, the width of a letter “n” in the font current when the macro is called. See
section “Numerical Expressions” in groff(7) for further details. An indent specified in a
call to .IP, .TP, or the deprecated .HP persists until (1) another of these macros is
called with an explicit indent argument, or (2) .SH, .SS, or .PP or its synonyms is
called; these clear the indent entirely.

Indents set by .RS move the left margin and persist until .RS, .RE, .SH, or .SS is called.
The default indentation, exhibited by ordinary .PP paragraphs not within an .RS/.RE
relative indent, is 7.2n in troff mode and 7n in nroff mode. The HTML output device is an
exception; it ignores indentation completely. This same indentation is used again
(additively) for the defaults of .IP, .TP, .RS, and the deprecated .HP. Section headings
(.SH) are set flush with the left margin of the output device, and subsection headings
(.SS) are indented 3n.

Resist the temptation to mock up tabular or multi-column output with ASCII tab characters
or the indentation arguments to .IP, .TP, .RS, or the deprecated .HP; the result may not
render comprehensibly on an output device you fail to check, or which is developed in the
future. The table preprocessor tbl(1) can likely meet your needs.

The following macros cause a line break with the insertion of vertical space: .SH, .SS,
.TP, .TQ, .PP (and its synonyms), .IP, and the deprecated .HP. The default inter-section
and inter-paragraph spacing is 1 line in nroff mode, and 0.4v in troff mode. (The
deprecated macro .PD can change this vertical spacing, but its use is discouraged.) The
macros .RS, .RE, .EX, and .EE also cause a break but no insertion of vertical space.

Number registers
Number registers are described in section “Options” below.

String registers
The following strings are defined.

\*R expands to the character escape for the “registered sign” glyph, ‘\(rg’, if
available, and “(Reg.)” otherwise.

\*S expands to an escape setting the font size to the document default.

\*(HF expands to the font identifier used to print headings and subheadings. The default
is ‘B’.

\*(lq
\*(rq expand to the character escapes for left and right double-quotation marks, ‘\(lq’
and ‘\(rq’, respectively.

\*(Tm expands to the character escape for the “trade mark sign” glyph, ‘\(tm’, if
available, and “(TM)” otherwise.

Interaction with preprocessors
When a preprocessor like tbl or eqn is needed, a hint can be given to the man page
formatter by making the first line of a man page look like this:

'\" word

Note that the line starts with an apostrophe ('), not a dot, and that a single space
character follows the double quote. The word consists of one letter for each needed
preprocessor: ‘e’ for eqn, ‘r’ for refer, and ‘t’ for tbl. Modern implementations of the
man program interpret this first line and automatically call the right preprocessor(s).

The usual tbl and eqn macros for table and equation inclusion, .TS, .T&, .TE, .EQ, and
.EN, may be used freely. Note that nroff output devices are extremely limited in
presentation of mathematical equations.

Portability
The two major syntactical categories of roff languages are requests and escapes. Since
the man macros are implemented in terms of groff requests and escapes, one can, in
principle, supplement the functionality of man with these lower-level elements where
necessary.

Note, however, that using raw groff requests is likely to make your page render poorly on
the class of viewers that transform it to HTML. Some requests make implicit assumptions
about things like character and page sizes that may not hold in an HTML environment; also,
many of these viewers don't interpret the full groff vocabulary, a problem that can lead
to portions of your text being silently dropped.

For portability to modern viewers, it is best to write your page entirely with the macros
described in this page (except for the ones identified as deprecated, which should be
avoided). The macros we have described as extensions (.EX/.EE, .SY/.OP/.YS, .UR/.UE, and
.MT/.ME) should be used with caution, as they may not yet be built in to some viewer that
is important to your audience. If in doubt, copy the implementation into your page—after
the .TH call and the “Name” section, to accommodate timid mandb implementations.

Similar caveats apply to escapes. Some escape sequences are however required for correct
typesetting even in man pages and usually do not cause portability problems:

\" Comment. Everything after the double-quote to the end of the input line is
ignored. Whole-line comments are frequently placed immediately after the empty
request ‘.’.

\newline
Join the next input line to the current one. Except for the update of the input
line counter (used for diagnostic messages and related purposes), a series of lines
ending in backslash-newline is transparent to groff. Use this escape to break
excessively input long lines for document maintenance.

\~ Adjustable, non-breaking space character. Use this escape to prevent a break
inside a short phrase or between a numerical quantity and its corresponding
unit(s).

Before starting the motor, set the output speed to\~1.
There are 1,024\~bytes in 1\~kiB.
CSTR\~#8 documents the B language.

\& Zero-width space. Append to an input line to prevent an end-of-sentence
punctuation sequence from being recognized as such, or insert at the beginning of
an input line to prevent a dot or apostrophe from being interpreted as the
beginning of a roff request.

\(aq ASCII apostrophe. Use for syntax elements of programming languages because some
output devices might replace unescaped apostrophes with right single quotation
marks.

\(oq Opening single quotation mark.
\(cq Closing single quotation mark.

Use these for paired directional single quotes, ‘like this’.

\(dq ASCII double-quote. Sometimes needed after macro calls to prevent the
interpretation of the ASCII quotation mark character ‘"’ as the beginning or end of
a macro argument.

\(lq Left double quotation mark.
\(rq Right double quotation mark.

Use these for paired directional double quotes, “like this”.

\(em Em-dash. Use for an interruption in a sentence—such as this one.

\(en En-dash. Use to separate the two ends of a range, in particular between numbers,
for example: the digits 1–9.

\(ga ASCII grave accent. Use for syntax elements of programming languages, for example
shell command substitutions, because some output devices might replace unescaped
grave accents with left single quotation marks.

\(ha ASCII circumflex accent. Use for syntax elements of programming languages because
some output devices might replace unescaped circumflex accents with non-ASCII
glyphs like the Unicode U+02C6 modifier letter circumflex.

\(ti ASCII tilde. Use for syntax elements of programming languages because some output
devices might replace unescaped tildes with non-ASCII glyphs like the Unicode
U+02DC small tilde.

\- Minus sign. Also use this to display syntax elements that require the ASCII
hyphen-minus character, for example command-line options and C language operators.
The unescaped ‘-’ input character is not appropriate for these cases because it may
render as a hyphen on some output devices.

\c If this escape sequence occurs at the end of an input line, no white space is
inserted between the last glyph on it and the first glyph resulting from the next
input line. This is occasionally useful when three different fonts are needed in a
single word.

Normally, the final output file should be named
.IB file .pdf\c
\&.

Note that when using this trick with the .BI or .RI macros, you will need to
manually add an italic correction escape ‘\/’ before the ‘\c’ due to way macros
expand their arguments.

Files processed with
.B groff \-mom
(or
.BI "\-m " mom\/\c
) produce PostScript output by default.

Alternatively, and perhaps with better portability, the ‘\f’ font escape sequence
can be used; see below. Using ‘\c’ to include the output from more than one input
line into the next-line argument of a .TP macro will render incorrectly with groff
1.22.3, mandoc 1.14.1, older versions of these programs, and perhaps with some
other formatters.

\e Widely used in man pages to represent a backslash output glyph. It works reliably
as long as the .ec request is not used, which should never happen in man pages, and
it is slightly more portable than the more exact ‘\(rs’ (“reverse solidus”) escape
sequence.

\fB, \fI, \fR, \fP
Switch to bold, italic, roman, or back to the previous font, respectively. Either
these or ‘\c’ is needed when three different fonts are required in a single
whitespace-delimited word.

.RB [ \-\-reference\-dictionary=\fI\,name\/\fP ]

.RB [ \-\-reference\-dictionary=\c
.IR name ]

Font escapes may be more portable than ‘\c’. As shown above, it is up to you to
account for italic corrections with ‘\/’ and ‘\,’, which are themselves groff
extensions, if desired and if supported by your implementation.

Note that ‘\fP’ reliably returns to the style in use immediately preceding the
previous ‘\f’ escape only if no sectioning, paragraph, or font face macro calls
have intervened.

As long as only two fonts are needed in any single whitespace-delimited word, font
alternation macros like .BI usually result in more readable source code than ‘\f’
escapes do.

For maximum portability, escape sequences and special characters not listed above are
better avoided in man pages.

Deprecated features
Use of the following is discouraged.

.AT [system [release]]
Alter the footer for use with AT&T man pages, overriding any definition of the
footer-outside argument to .TH. This macro exists only for compatibility; don't
use it.

The first argument system can be:

3 7th edition (default)

4 System III

5 System V

The optional second argument release specifies the release number, such as in
“System V Release 3”.

.BT Set the page footer. Redefine this macro to get control of the footer.

.DT Set tabs every 0.5 inches. Since this macro is always called during a .TH macro,
it makes sense to call it only if the tab positions have been changed.

Use of this presentation-level macro is deprecated. It translates poorly to HTML,
under which exact whitespace control and tabbing are not readily available. Thus,
information or distinctions that you use .DT to express are likely to be lost. If
you feel tempted to use it, you should probably be composing a table using tbl(1)
markup instead.

.HP [indent]
Set up a paragraph with a hanging left indentation. The indent argument, if
present, is handled as with .TP.

Use of this presentation-level macro is deprecated. While it is universally
portable to legacy Unix systems, a hanging indentation cannot be expressed
naturally under HTML, and many HTML-based manual viewers simply interpret it as a
starter for a normal paragraph. Thus, any information or distinction you tried to
express with the indentation may be lost.

.PD [vertical-space]
Define the vertical space between paragraphs or (sub)sections. The optional
argument vertical-space specifies the amount of space; the default scaling is ‘v’).
Without an argument, the spacing is reset to its default value; see “Horizontal and
vertical spacing” above.

Use of this presentation-level macro is deprecated. It translates poorly to HTML,
under which exact control of inter-paragraph spacing is not readily available.
Thus, information or distinctions that you use .PD to express are likely to be
lost.

.PT Set the page header. Redefine this macro to get control of the header.

.UC [version]
Alter the footer for use with BSD man pages, overriding any definition of the
footer-outside argument to .TH. This macro exists only for compatibility; don't
use it.

The argument version can be:

3 3rd Berkeley Distribution (default)

4 4th Berkeley Distribution

5 4.2 Berkeley Distribution

6 4.3 Berkeley Distribution

7 4.4 Berkeley Distribution

History
According to its own man(7) page, Version 7 Unix (1979) supported all of the macros
described in this page not listed as GNU extensions, except .P, .SB, .SS, and the
deprecated .AT, .BT, .PT, and .UC. The only string registers defined were R and S; no
number registers were documented.

OPTIONS

The following groff options set number registers recognized and used by the man macro
package.

-rcR=1 Continuous rendering. Create a single, very long page instead of multiple pages.
This is the default in nroff mode. Use -rcR=0 to disable it.

-rC1 Number pages continuously. If more than one man page is given on the command line,
number the pages continuously, rather than starting each at 1.

-rD1 Enable double-sided printing. Footers for even and odd pages are formatted
differently; see the description of .TH in “Document structure macros”, above.

-rFT=footer-distance
Set distance of the footer, relative to the bottom of the page if negative or
relative to the top if positive, to footer-distance. The default is -0.5i.

-rHY=flags
Set hyphenation flags. Permissible values of flags are documented in section
“Hyphenation” of groff(7). The default is 4 if continuous rendering is enabled
(-rcR=1 above), and 6 otherwise.

-rIN=indent
Set the body text indentation (for normal paragraphs) to indent. See “Horizontal
and vertical spacing” above for the default indentation value. For nroff, indent
should always be an integer multiple of unit ‘n’ to get consistent indentation.

-rLL=line-length
Set line length. If this option is not given, the line length is set to respect
any value set by a prior “.ll” request (which must be in effect when the .TH macro
is invoked), if this differs from the built-in default for the formatter; otherwise
it defaults to 78n in nroff mode and 6.5i in troff mode.

Note that the use of a “.ll” request to initialize the line length is supported for
backward compatibility with some versions of the man program; direct initialization
of the LL register should always be preferred to the use of such a request. In
particular, note that a “.ll 65n” request does not preserve the normal nroff
default line length (the man default initialization to 78n prevails), whereas the
-rLL=65n option, or an equivalent “.nr LL 65n” request preceding the use of the .TH
macro, does set a line length of 65n.

-rLT=title-length
Set title length. If this option is not given, the title length defaults to the
line length.

-rPn Start enumeration of pages at n rather than 1.

-rSpoint-size
Use point-size as the base document font size. Acceptable values are 10, 11, or
12. See subsection “Font style macros” above for the default.

-rSN=subsection-indent
Set subsection indentation to subsection-indent. See “Horizontal and vertical
spacing” above for the default indentation value.

-rXp After page p, number pages as pa, pb, pc, and so forth. For example, the option
-rX2 produces the following page numbers: 1, 2, 2a, 2b, 2c, and so on.

FILES

       /usr/share/groff/1.22.4/tmac/man.tmac
       /usr/share/groff/1.22.4/tmac/an.tmac
              These are wrapper files to call andoc.tmac.

       /usr/share/groff/1.22.4/tmac/andoc.tmac
              This brief groff program detects whether the man or mdoc  macro  package  is  being
              used by a document and loads the correct macro definitions, taking advantage of the
              fact that pages using them must call .TH  or  .Dd,  respectively,  as  their  first
              macro.   Because  the  wrappers above load this file, a man program or user typing,
              for example, “groff -man page.1”, need not know which package the file page.1 uses.
              Multiple man pages, in either format, can be handled.

       /usr/share/groff/1.22.4/tmac/an-old.tmac
              Most  man macros are contained in this file.  It also loads the GNU extensions from
              an-ext.tmac (see below).

       /usr/share/groff/1.22.4/tmac/an-ext.tmac
              The extension macro definitions for .SY,  .OP,  .YS,  .TQ,  .EX/.EE,  .UR/.UE,  and
              .MT/.ME  are  contained  in  this  file,  which  is  written  in  classic troff and
              permissively licensed—not copylefted.  Man page authors concerned about portability
              to  legacy  Unix systems are encouraged to copy these definitions into their pages,
              and maintainers of troff implementations or  work-alike  systems  that  format  man
              pages are encouraged to re-use them.

              Note  that the definitions for these macros are read after the call of .TH, so they
              will replace any macros of the same names preceding it in your file.   If  you  use
              your own implementations of these macros, they must be defined after calling .TH to
              have any effect.

       /usr/share/groff/site-tmac/man.local
              Local changes and customizations should be put into this file.

NOTES

Some tips on troubleshooting your man pages follow.

• .RS doesn't indent relative to my indented paragraph
The .RS macro sets the indentation relative to the amount of a normal paragraph
(.PP and its synonyms). The same default indentation amount is used for .RS, .IP,
.TP, and the deprecated .HP. If you need to start an indent relative to an
indented paragraph, call .RS repeatedly until an acceptable indentation is
achieved, or give .RS an indentation argument that is at least as much as the
paragraph's indentation amount relative to an adjacent .PP paragraph. See
“Horizontal and vertical spacing” above for the values.

• .RE doesn't reset the indent to the expected level
• warning: scale indicator invalid in this context
• warning: number register 'an-saved-marginn' not defined
• warning: number register 'an-saved-prevailing-indentn' not defined
The .RS macro takes an indentation amount as an argument; the .RE macro's argument
is a specific indentation level. .RE 1 goes to the level before any .RS macros
were called, .RE 2 goes to the level of the first .RS call you made, and so forth.
If you desire symmetry in your macro calls, simply issue one .RE without an
argument for each .RS that precedes it.

After calls to the .SH and .SS sectioning macros, all relative indents are cleared
and calls to .RE have no effect.

AUTHORS

       The GNU version of the man macro package was written by James Clark and contributors.  The
       extension macros were written by Werner Lemberg ⟨wl@gnu.org⟩ and  Eric  S.  Raymond  ⟨esr@
       thyrsus.com⟩.

       This document was originally written for the Debian GNU/Linux system by Susan G. Kleinmann
       ⟨sgk@debian.org⟩.  It was corrected and updated by Werner Lemberg and G. Branden Robinson.
       The  extension  macros  were  documented  by  Eric  S.  Raymond;  he  also  originated the
       portability section, to which Ingo Schwarze contributed most of  the  material  on  escape
       sequences.