roff - roff language reference for mandoc
The roff language is a general purpose text formatting
language. Since traditional implementations of the mdoc(7) and man(7) manual
formatting languages are based on it, many real-world manuals use small
numbers of roff requests and escape sequences intermixed with their
mdoc(7) or man(7) code. To properly format such manuals, the mandoc(1)
utility supports a subset of roff requests and escapes. Even though
this manual page lists all roff requests and escape sequences, it
only contains partial information about requests not supported by mandoc(1)
and about language features that do not matter for manual pages. For
complete roff manuals, consult the SEE ALSO section.
Input lines beginning with the control character ‘.’
are parsed for requests and macros. Such lines are called “request
lines” or “macro lines”, respectively. Requests change
the processing state and manipulate the formatting; some macros also define
the document structure and produce formatted output. The single quote
("'") is accepted as an alternative control character, treated by
mandoc(1) just like ‘.’
Lines not beginning with control characters are called
“text lines”. They provide free-form text to be printed; the
formatting of the text depends on the respective processing context.
roff documents may contain only graphable 7-bit ASCII
characters, the space character, and, in certain circumstances, the tab
character. The backslash character ‘\’ indicates the start of
an escape sequence, used for example for Comments and Special
Characters. For a complete listing of escape sequences, consult the
ESCAPE SEQUENCE REFERENCE below.
Text following an escaped double-quote ‘\"’,
whether in a request, macro, or text line, is ignored to the end of the
line. A request line beginning with a control character and comment escape
‘.\"’ is also ignored. Furthermore, request lines with
only a control character and optional trailing whitespace are stripped from
input.
Examples:
.\" This is a comment line.
.\" The next line is ignored:
.
.Sh EXAMPLES \" This is a comment, too.
example text \" And so is this.
Special characters are used to encode special glyphs and are
rendered differently across output media. They may occur in request, macro,
and text lines. Sequences begin with the escape character ‘\’
followed by either an open-parenthesis ‘(’ for two-character
sequences; an open-bracket ‘[’ for n-character sequences
(terminated at a close-bracket ‘]’); or a single one character
sequence.
Examples:
- \(em
- Two-letter em dash escape.
- \e
- One-letter backslash escape.
See mandoc_char(7) for a complete list.
In mdoc(7) and man(7) documents, fonts are usually selected with
macros. The \f escape sequence and the ft request can be used
to manually change the font, but this is not recommended in mdoc(7)
documents. Such manual font changes are overridden by many subsequent
macros.
The following fonts are supported:
- B
- Bold font.
- BI
- A font that is both bold and italic.
- CB
- Bold constant width font. Same as B in terminal output.
- CI
- Italic constant width font. Same as I in terminal output.
- CR
- Regular constant width font. Same as R in terminal output.
- CW
- An alias for CR.
- I
- Italic font.
- P
- Return to the previous font. If a macro caused a font change since the
last \f eascape sequence or ft request, this returns to the
font before the last font change in the macro rather than to the font
before the last manual font change.
- R
- Roman font. This is the default font.
- 1
- An alias for R.
- 2
- An alias for I.
- 3
- An alias for B.
- 4
- An alias for BI.
Examples:
Whitespace consists of the space character. In text lines,
whitespace is preserved within a line. In request and macro lines,
whitespace delimits arguments and is discarded.
Unescaped trailing spaces are stripped from text line input unless
in a literal context. In general, trailing whitespace on any input line is
discouraged for reasons of portability. In the rare case that a space
character is needed at the end of an input line, it may be forced by
‘\ \&’.
Literal space characters can be produced in the output using
escape sequences. In macro lines, they can also be included in arguments
using quotation; see MACRO SYNTAX for details.
Blank text lines, which may include whitespace, are only permitted
within literal contexts. If the first character of a text line is a space,
that line is printed with a leading newline.
Many requests and macros support scaled widths for their
arguments. The syntax for a scaled width is
‘[+-]?[0-9]*.[0-9]*[:unit:]’, where a decimal must be preceded
or followed by at least one digit.
The following scaling units are accepted:
- c
- centimetre
- i
- inch
- P
- pica (1/6 inch)
- p
- point (1/72 inch)
- f
- scale ‘u’ by 65536
- v
- default vertical span
- m
- width of rendered ‘m’ (em) character
- n
- width of rendered ‘n’ (en) character
- u
- default horizontal span for the terminal
- M
- mini-em (1/100 em)
Using anything other than ‘m’, ‘n’, or
‘v’ is necessarily non-portable across output media. See
COMPATIBILITY.
If a scaling unit is not provided, the numerical value is
interpreted under the default rules of ‘v’ for vertical spaces
and ‘u’ for horizontal ones.
Examples:
- .Bl -tag -width 2i
- two-inch tagged list indentation in mdoc(7)
- .HP 2i
- two-inch tagged list indentation in man(7)
- .sp 2v
- two vertical spaces
Each sentence should terminate at the end of an input line. By
doing this, a formatter will be able to apply the proper amount of spacing
after the end of sentence (unescaped) period, exclamation mark, or question
mark followed by zero or more non-sentence closing delimiters
(‘)’, ‘]’, ‘'’,
‘"’) .
The proper spacing is also intelligently preserved if a sentence
ends at the boundary of a macro line.
If an input line happens to end with a period, exclamation or
question mark that isn't the end of a sentence, append a zero-width space
(‘\&’).
Examples:
Do not end sentences mid-line like this. Instead,
end a sentence like this.
A macro would end like this:
.Xr mandoc 1 .
An abbreviation at the end of an input line needs escaping, e.g.\&
like this.
A request or macro line consists of:
- 1.
- the control character ‘.’ or ‘'’ at the
beginning of the line,
- 2.
- optionally an arbitrary amount of whitespace,
- 3.
- the name of the request or the macro, which is one word of arbitrary
length, terminated by whitespace,
- 4.
- and zero or more arguments delimited by whitespace.
Thus, the following request lines are all equivalent:
Macros are provided by the mdoc(7) and man(7) languages and can be
defined by the de request. When called, they follow the same syntax
as requests, except that macro arguments may optionally be quoted by
enclosing them in double quote characters (‘"’). Quoted
text, even if it contains whitespace or would cause a macro invocation when
unquoted, is always considered literal text. Inside quoted text, pairs of
double quote characters (‘""’) resolve to single
double quote characters.
To be recognised as the beginning of a quoted argument, the
opening quote character must be preceded by a space character. A quoted
argument extends to the next double quote character that is not part of a
pair, or to the end of the input line, whichever comes earlier. Leaving out
the terminating double quote character at the end of the line is
discouraged. For clarity, if more arguments follow on the same input line,
it is recommended to follow the terminating double quote character by a
space character; in case the next character after the terminating double
quote character is anything else, it is regarded as the beginning of the
next, unquoted argument.
Both in quoted and unquoted arguments, pairs of backslashes
(‘\\’) resolve to single backslashes. In unquoted arguments,
space characters can alternatively be included by preceding them with a
backslash (‘\ ’), but quoting is usually better for
clarity.
Examples:
- .Fn strlen "const char *s"
- Group arguments "const char *s" into one function argument. If
unspecified, "const", "char", and "*s" would
be considered separate arguments.
- .Op "Fl a"
- Consider "Fl a" as literal text instead of a flag macro.
The mandoc(1) roff parser recognises the following
requests. For requests marked as "ignored" or
"unsupported", any arguments are ignored, and the number of
arguments is not checked.
- ab
[message]
- Abort processing. Currently unsupported.
- ad [b | c |
l | n | r]
- Set line adjustment mode for subsequent text. Currently ignored.
- af registername
format
- Assign an output format to a number register. Currently ignored.
- aln newname
oldname
- Create an alias for a number register. Currently unsupported.
- als newname
oldname
- Create an alias for a request, string, macro, or diversion.
- am macroname
[endmacro]
- Append to a macro definition. The syntax of this request is the same as
that of de.
- am1 macroname
[endmacro]
- Append to a macro definition, switching roff compatibility mode off during
macro execution (groff extension). The syntax of this request is the same
as that of de1. Since mandoc(1) does not implement roff
compatibility mode at all, it handles this request as an alias for
am.
- ami macrostring
[endstring]
- Append to a macro definition, specifying the macro name indirectly (groff
extension). The syntax of this request is the same as that of
dei.
- ami1 macrostring
[endstring]
- Append to a macro definition, specifying the macro name indirectly and
switching roff compatibility mode off during macro execution (groff
extension). The syntax of this request is the same as that of dei1.
Since mandoc(1) does not implement roff compatibility mode at all,
it handles this request as an alias for ami.
- as stringname
[string]
- Append to a user-defined string. The syntax of this request is the same as
that of ds. If a user-defined string with the specified name does
not yet exist, it is set to the empty string before appending.
- as1 stringname
[string]
- Append to a user-defined string, switching roff compatibility mode off
during macro execution (groff extension). The syntax of this request is
the same as that of ds1. Since mandoc(1) does not implement
roff compatibility mode at all, it handles this request as an alias
for as.
- asciify
divname
- Fully unformat a diversion. Currently unsupported.
- backtrace
- Print a backtrace of the input stack. This is a groff extension and
currently ignored.
- bd font
[curfont] [offset]
- Artificially embolden by repeated printing with small shifts. Currently
ignored.
- bleedat left
top width height
- Set the BleedBox page parameter for PDF generation. This is a Heirloom
extension and currently ignored.
- blm
macroname
- Set a blank line trap. Currently unsupported.
- box
divname
- Begin a diversion without including a partially filled line. Currently
unsupported.
- boxa
divname
- Add to a diversion without including a partially filled line. Currently
unsupported.
- bp
[+|-]pagenumber
- Begin a new page. Currently ignored.
- BP source height width
position offset flags label
- Define a frame and place a picture in it. This is a Heirloom extension and
currently unsupported.
- br
- Break the output line.
- break
-
Break out of the innermost while loop.
- breakchar
char ...
- Optional line break characters. This is a Heirloom extension and currently
ignored.
- brnl N
- Break output line after the next N input lines. This is a Heirloom
extension and currently ignored.
- brp
- Break and spread output line. Currently, this is implemented as an alias
for br.
- brpnl
N
- Break and spread output line after the next N input lines. This is
a Heirloom extension and currently ignored.
- c2 [char]
- Change the no-break control character. Currently unsupported.
- cc [char]
- Change the control character. If char is not specified, the control
character is reset to ‘.’. Trailing characters are
ignored.
- ce [N]
- Center the next N input lines without filling. N defaults to
1. An argument of 0 or less ends centering. Currently, high level macros
abort centering.
- cf filename
- Output the contents of a file. Ignored because insecure.
- cflags flags
char ...
- Set character flags. This is a groff extension and currently ignored.
- ch macroname
[dist]
- Change a trap location. Currently ignored.
- char glyph
[string]
- Define or redefine the ASCII character or character escape sequence
glyph to be rendered as string, which can be empty. Only
partially supported in mandoc(1); may interact incorrectly with
tr.
- chop
stringname
- Remove the last character from a macro, string, or diversion. Currently
unsupported.
- class classname
char ...
- Define a character class. This is a groff extension and currently
ignored.
- close
streamname
- Close an open file. Ignored because insecure.
- CL color
text
- Print text in color. This is a Heirloom extension and currently
unsupported.
- color [1 |
0]
- Activate or deactivate colors. This is a groff extension and currently
ignored.
- composite
from to
- Define a name component for composite glyph names. This is a groff
extension and currently unsupported.
- continue
- Immediately start the next iteration of a while loop. Currently
unsupported.
- cp [1 |
0]
- Switch roff compatibility mode on or off. Currently ignored.
- cropat left top
width height
- Set the CropBox page parameter for PDF generation. This is a Heirloom
extension and currently ignored.
- cs font
[width [emsize]]
- Constant character spacing mode. Currently ignored.
- cu [N]
- Underline next N input lines including whitespace. Currently
ignored.
- da divname
- Append to a diversion. Currently unsupported.
- dch macroname
[dist]
- Change a trap location in the current diversion. This is a Heirloom
extension and currently unsupported.
- de macroname
[endmacro]
- Define a roff macro. Its syntax can be either
.de macroname
definition
..
or
.de macroname endmacro
definition
.endmacro
Both forms define or redefine the macro macroname to
represent the definition, which may consist of one or more input
lines, including the newline characters terminating each line, optionally
containing calls to roff requests, roff macros or high-level
macros like man(7) or mdoc(7) macros, whichever applies to the document in
question.
Specifying a custom endmacro works in the same way as for
ig; namely, the call to ‘.endmacro’ first ends
the definition, and after that, it is also evaluated as a roff
request or roff macro, but not as a high-level macro.
The macro can be invoked later using the syntax
.macroname [argument [argument
...]]
Regarding argument parsing, see MACRO SYNTAX above.
The line invoking the macro will be replaced in the input stream
by the definition, replacing all occurrences of \\$N, where
N is a digit, by the Nth argument. For example,
.de ZN
\fI\^\\$1\^\fP\\$2
..
.ZN XtFree .
produces
\fI\^XtFree\^\fP.
in the input stream, and thus in the output: XtFree. Each
occurrence of \\$* is replaced with all the arguments, joined together with
single space characters. The variant \\$@ is similar, except that each
argument is individually quoted.
Since macros and user-defined strings share a common string table,
defining a macro macroname clobbers the user-defined string
macroname, and the definition can also be printed using the
‘\*’ string interpolation syntax described below ds,
but this is rarely useful because every macro definition contains at least
one explicit newline character.
In order to prevent endless recursion, both groff and mandoc(1)
limit the stack depth for expanding macros and strings to a large, but
finite number, and mandoc(1) also limits the length of the expanded input
line. Do not rely on the exact values of these limits.
- de1 macroname
[endmacro]
- Define a roff macro that will be executed with roff
compatibility mode switched off during macro execution. This is a groff
extension. Since mandoc(1) does not implement roff compatibility
mode at all, it handles this request as an alias for de.
- defcolor
newname scheme component ...
- Define a color name. This is a groff extension and currently ignored.
- dei macrostring
[endstring]
- Define a roff macro, specifying the macro name indirectly (groff
extension). The syntax of this request is the same as that of de.
The effect is the same as:
.de \*[macrostring]
[\*[endstring]]
- dei1 macrostring
[endstring]
- Define a roff macro that will be executed with roff
compatibility mode switched off during macro execution, specifying the
macro name indirectly (groff extension). Since mandoc(1) does not
implement roff compatibility mode at all, it handles this request
as an alias for dei.
- device string
...
- devicem
stringname
- These two requests only make sense with the groff-specific intermediate
output format and are unsupported.
- di divname
- Begin a diversion. Currently unsupported.
- do command
[argument ...]
- Execute roff request or macro line with compatibility mode
disabled. Currently unsupported.
- ds stringname
[["]string]
- Define a user-defined string. The stringname and string
arguments are space-separated. If the string begins with a
double-quote character, that character will not be part of the string. All
remaining characters on the input line form the string, including
whitespace and double-quote characters, even trailing ones.
The string can be interpolated into subsequent text by
using \*[stringname] for a stringname of arbitrary length,
or \*(NN or \*N if the length of stringname is two or one
characters, respectively. Interpolation can be prevented by escaping the
leading backslash; that is, an asterisk preceded by an even number of
backslashes does not trigger string interpolation.
Since user-defined strings and macros share a common string
table, defining a string stringname clobbers the macro
stringname, and the stringname used for defining a string
can also be invoked as a macro, in which case the following input line
will be appended to the string, forming a new input line passed
to the roff parser. For example,
.ds badidea .S
.badidea
H SYNOPSIS
invokes the SH macro when used in a man(7) document. Such
abuse is of course strongly discouraged.
- ds1 stringname
[["]string]
- Define a user-defined string that will be expanded with roff
compatibility mode switched off during string expansion. This is a groff
extension. Since mandoc(1) does not implement roff compatibility
mode at all, it handles this request as an alias for ds.
- dwh dist
macroname
- Set a location trap in the current diversion. This is a Heirloom extension
and currently unsupported.
- dt [dist
macroname]
- Set a trap within a diversion. Currently unsupported.
- ec [char]
- Enable the escape mechanism and change the escape character. The
char argument defaults to the backslash (‘\’).
- ecr
- Restore the escape character. Currently unsupported.
- ecs
- Save the escape character. Currently unsupported.
- el body
- The “else” half of an if/else conditional. Pops a result off
the stack of conditional evaluations pushed by ie and uses it as
its conditional. If no stack entries are present (e.g., due to no prior
ie calls) then false is assumed. The syntax of this request is
similar to if except that the conditional is missing.
- em
macroname
- Set a trap at the end of input. Currently unsupported.
- EN
- End an equation block. See EQ.
- eo
- Disable the escape mechanism completely.
- EP
- End a picture started by BP. This is a Heirloom extension and
currently unsupported.
- EQ
- Begin an equation block. See eqn(7) for a description of the equation
language.
- errprint
message
- Print a string like an error message. This is a Heirloom extension and
currently ignored.
- ev
[envname]
- Switch to another environment. Currently unsupported.
- evc
[envname]
- Copy an environment into the current environment. Currently
unsupported.
- ex
- Abort processing and exit. Currently unsupported.
- fallback
curfont font ...
- Select the fallback sequence for a font. This is a Heirloom extension and
currently ignored.
- fam
[familyname]
- Change the font family. This is a groff extension and currently
ignored.
- fc [delimchar
[padchar]]
- Define a delimiting and a padding character for fields. Currently
unsupported.
- fchar
glyphname [string]
- Define a fallback glyph. Currently unsupported.
- fcolor
colorname
- Set the fill color for \D objects. This is a groff extension and currently
ignored.
- fdeferlig
font string ...
- Defer ligature building. This is a Heirloom extension and currently
ignored.
- feature
+|-name
- Enable or disable an OpenType feature. This is a Heirloom extension and
currently ignored.
- fi
- Break the output line and switch to fill mode, which is active by default
but can be ended with the nf request. In fill mode, input from
subsequent input lines is added to the same output line until the next
word no longer fits, at which point the output line is broken. This
request is implied by the mdoc(7) Sh macro and by the man(7)
SH, SS, and EE macros.
- fkern font
minkern
- Control the use of kerning tables for a font. This is a Heirloom extension
and currently ignored.
- fl
- Flush output. Currently ignored.
- flig font string
char ...
- Define ligatures. This is a Heirloom extension and currently ignored.
- fp position font
[filename]
- Assign font position. Currently ignored.
- fps mapname
...
- Mount a font with a special character map. This is a Heirloom extension
and currently ignored.
- fschar font
glyphname [string]
- Define a font-specific fallback glyph. This is a groff extension and
currently unsupported.
- fspacewidth
font [afmunits]
- Set a font-specific width for the space character. This is a Heirloom
extension and currently ignored.
- fspecial
curfont [font ...]
- Conditionally define a special font. This is a groff extension and
currently ignored.
- ft [font]
- Change the font; see Font Selection. The font argument
defaults to P.
- ftr newname
[oldname]
- Translate font name. This is a groff extension and currently ignored.
- fzoom font
[permille]
- Zoom font size. Currently ignored.
- gcolor
[colorname]
- Set glyph color. This is a groff extension and currently ignored.
- hc [char]
- Set the hyphenation character. Currently ignored.
- hcode char code
...
- Set hyphenation codes of characters. Currently ignored.
- hidechar
font char ...
- Hide characters in a font. This is a Heirloom extension and currently
ignored.
- hla
language
- Set hyphenation language. This is a groff extension and currently
ignored.
- hlm
[number]
- Set maximum number of consecutive hyphenated lines. Currently
ignored.
- hpf
filename
- Load hyphenation pattern file. This is a groff extension and currently
ignored.
- hpfa
filename
- Load hyphenation pattern file, appending to the current patterns. This is
a groff extension and currently ignored.
- hpfcode code
code ...
- Define mapping values for character codes in hyphenation patterns. This is
a groff extension and currently ignored.
- hw word ...
- Specify hyphenation points in words. Currently ignored.
- hy [mode]
- Set automatic hyphenation mode. Currently ignored.
- hylang
language
- Set hyphenation language. This is a Heirloom extension and currently
ignored.
- hylen
nchar
- Minimum word length for hyphenation. This is a Heirloom extension and
currently ignored.
- hym
[length]
- Set hyphenation margin. This is a groff extension and currently
ignored.
- hypp penalty
...
- Define hyphenation penalties. This is a Heirloom extension and currently
ignored.
- hys
[length]
- Set hyphenation space. This is a groff extension and currently
ignored.
- ie condition
body
- The “if” half of an if/else conditional. The result of the
conditional is pushed into a stack used by subsequent invocations of
el, which may be separated by any intervening input (or not exist
at all). Its syntax is equivalent to if.
- if condition
body
- Begin a conditional. This request can also be written as follows:
.if condition \{body
body ...\}
.if condition \{\
body ...
.\}
The condition is a boolean expression. Currently, mandoc(1)
supports the following subset of roff conditionals:
- •
- If ‘!’ is prefixed to condition, it is logically
inverted.
- •
- If the first character of condition is ‘n’ (nroff
mode) or ‘o’ (odd page), it evaluates to true, and the
body starts with the next character.
- •
- If the first character of condition is ‘e’ (even
page), ‘t’ (troff mode), or ‘v’ (vroff mode),
it evaluates to false, and the body starts with the next
character.
- •
- If the first character of condition is ‘c’ (character
available), it evaluates to true if the following character is an ASCII
character or a valid character escape sequence, or to false otherwise. The
body starts with the character following that next character.
- •
- If the first character of condition is ‘d’, it
evaluates to true if the rest of condition is the name of an
existing user defined macro or string; otherwise, it evaluates to
false.
- •
- If the first character of condition is ‘r’, it
evaluates to true if the rest of condition is the name of an
existing number register; otherwise, it evaluates to false.
- •
- If the condition starts with a parenthesis or with an optionally
signed integer number, it is evaluated according to the rules of
Numerical expressions explained below. It evaluates to true if the
result is positive, or to false if the result is zero or negative.
- •
- Otherwise, the first character of condition is regarded as a
delimiter and it evaluates to true if the string extending from its first
to its second occurrence is equal to the string extending from its second
to its third occurrence.
- •
- If condition cannot be parsed, it evaluates to false.
If a conditional is false, its children are not processed, but are
syntactically interpreted to preserve the integrity of the input document.
Thus,
.if t .ig
will discard the ‘.ig’, which may lead to
interesting results, but
.if t .if t \{\
will continue to syntactically interpret to the block close of the
final conditional. Sub-conditionals, in this case, obviously inherit the
truth value of the parent.
If the body section is begun by an escaped brace
‘\{’, scope continues until the end of the input line
containing the matching closing-brace escape sequence ‘\}’. If
the body is not enclosed in braces, scope continues until the end of
the line. If the condition is followed by a body on the same
line, whether after a brace or not, then requests and macros must
begin with a control character. It is generally more intuitive, in this
case, to write
.if condition \{\
.request
.\}
than having the request or macro follow as
.if condition \{.request
The scope of a conditional is always parsed, but only executed if
the conditional evaluates to true.
Note that the ‘\}’ is converted into a zero-width
escape sequence if not passed as a standalone macro ‘.\}’. For
example,
.Fl a \} b
will result in ‘\}’ being considered an argument of
the ‘Fl’ macro.
- ig
[endmacro]
- Ignore input. Its syntax can be either
or
.ig endmacro
ignored text
.endmacro
In the first case, input is ignored until a ‘..’
request is encountered on its own line. In the second case, input is ignored
until the specified ‘.endmacro’ is encountered. Do not
use the escape character ‘\’ anywhere in the definition of
endmacro; it would cause very strange behaviour.
When the endmacro is a roff request or a roff macro, like
in
.ig if
the subsequent invocation of if will first terminate the
ignored text, then be invoked as usual. Otherwise, it only terminates
the ignored text, and arguments following it or the
‘..’ request are discarded.
- in
[[+|-]width]
- Change indentation. See man(7). Ignored in mdoc(7).
- index register
stringname substring
- Find a substring in a string. This is a Heirloom extension and currently
unsupported.
- it expression
macro
- Set an input line trap. The named macro will be invoked after
processing the number of input text lines specified by the numerical
expression. While evaluating the expression, the unit
suffixes described below Scaling Widths are ignored.
- itc expression
macro
- Set an input line trap, not counting lines ending with \c. Currently
unsupported.
- IX class
keystring
- To support the generation of a table of contents, pod2man(1) emits this
user-defined macro, usually without defining it. To avoid reporting large
numbers of spurious errors, mandoc(1) ignores it.
- kern [1 |
0]
- Switch kerning on or off. Currently ignored.
- kernafter
font char ... afmunits ...
- Increase kerning after some characters. This is a Heirloom extension and
currently ignored.
- kernbefore
font char ... afmunits ...
- Increase kerning before some characters. This is a Heirloom extension and
currently ignored.
- kernpair
font char ... font char ... afmunits
- Add a kerning pair to the kerning table. This is a Heirloom extension and
currently ignored.
- lc [glyph]
- Define a leader repetition character. Currently unsupported.
- lc_ctype
localename
- Set the LC_CTYPE locale. This is a Heirloom extension and currently
unsupported.
- lds macroname
string
- Define a local string. This is a Heirloom extension and currently
unsupported.
- length register
string
- Count the number of input characters in a string. Currently
unsupported.
- letadj lspmin
lshmin letss lspmax lshmax
- Dynamic letter spacing and reshaping. This is a Heirloom extension and
currently ignored.
- lf lineno
[filename]
- Change the line number for error messages. Ignored because insecure.
- lg [1 |
0]
- Switch the ligature mechanism on or off. Currently ignored.
- lhang font char
... afmunits
- Hang characters at left margin. This is a Heirloom extension and currently
ignored.
- linetabs
[1 | 0]
- Enable or disable line-tabs mode. This is a groff extension and currently
unsupported.
- ll
[[+|-]width]
- Change the output line length. If the width argument is omitted,
the line length is reset to its previous value. The default setting for
terminal output is 78n. If a sign is given, the line length is added to or
subtracted from; otherwise, it is set to the provided value. Using this
request in new manuals is discouraged for several reasons, among others
because it overrides the mandoc(1) -O width command line
option.
- lnr register
[+|-]value [increment]
- Set local number register. This is a Heirloom extension and currently
unsupported.
- lnrf register
[+|-]value [increment]
- Set local floating-point register. This is a Heirloom extension and
currently unsupported.
- lpfx
string
- Set a line prefix. This is a Heirloom extension and currently
unsupported.
- ls [factor]
- Set line spacing. It takes one integer argument specifying the vertical
distance of subsequent output text lines measured in v units. Currently
ignored.
- lsm
macroname
- Set a leading spaces trap. This is a groff extension and currently
unsupported.
- lt
[[+|-]width]
- Set title line length. Currently ignored.
- mc glyph
[dist]
- Print margin character in the right margin. The dist is currently
ignored; instead, 1n is used.
- mediasize
media
- Set the device media size. This is a Heirloom extension and currently
ignored.
- minss
width
- Set minimum word space. This is a Heirloom extension and currently
ignored.
- mk
[register]
- Mark vertical position. Currently ignored.
- mso
filename
- Load a macro file using the search path. Ignored because insecure.
- na
- Disable adjusting without changing the adjustment mode. Currently
ignored.
- ne [height]
- Declare the need for the specified minimum vertical space before the next
trap or the bottom of the page. Currently ignored.
- nf
- Break the output line and switch to no-fill mode. Subsequent input lines
are kept together on the same output line even when exceeding the right
margin, and line breaks in subsequent input cause output line breaks. This
request is implied by the mdoc(7) Bd -unfilled and Bd
-literal macros and by the man(7) EX macro. The fi
request switches back to the default fill mode.
- nh
- Turn off automatic hyphenation mode. Currently ignored.
- nhychar char
...
- Define hyphenation-inhibiting characters. This is a Heirloom extension and
currently ignored.
- nm [start
[inc [space [indent]]]]
- Print line numbers. Currently unsupported.
- nn [number]
- Temporarily turn off line numbering. Currently unsupported.
- nop body
- Execute the rest of the input line as a request, macro, or text line,
skipping the nop request and any space characters immediately
following it. This is mostly used to indent text lines inside macro
definitions.
- nr register
[+|-]expression [stepsize]
- Define or change a register. A register is an arbitrary string value that
defines some sort of state, which influences parsing and/or formatting.
For the syntax of expression, see Numerical expressions
below. If it is prefixed by a sign, the register will be incremented or
decremented instead of assigned to.
The stepsize is used by the \n+ auto-increment
feature. It remains unchanged when omitted while changing an existing
register, and it defaults to 0 when defining a new register.
The following register is handled specially:
- nS
- If set to a positive integer value, certain mdoc(7) macros will behave in
the same way as in the SYNOPSIS section. If set to 0, these macros
will behave in the same way as outside the SYNOPSIS section, even
when called within the SYNOPSIS section itself. Note that starting
a new mdoc(7) section with the Sh macro will reset this
register.
- nrf register
[+|-]expression
- [increment] Define or change a floating-point register. This is a
Heirloom extension and currently unsupported.
- nroff
-
Force nroff mode. This is a groff extension and currently ignored.
- ns
- Turn on no-space mode. Currently ignored.
- nx
[filename]
- Abort processing of the current input file and process another one.
Ignored because insecure.
- open stream
file
- Open a file for writing. Ignored because insecure.
- opena stream
file
- Open a file for appending. Ignored because insecure.
- os
- Output saved vertical space. Currently ignored.
- output
string
- Output directly to intermediate output. Not supported.
- padj [1 |
0]
- Globally control paragraph-at-once adjustment. This is a Heirloom
extension and currently ignored.
- papersize
media
- Set the paper size. This is a Heirloom extension and currently
ignored.
- pc [char]
- Change the page number character. Currently ignored.
- pev
- Print environments. This is a groff extension and currently ignored.
- pi command
- Pipe output to a shell command. Ignored because insecure.
- PI
- Low-level request used by BP. This is a Heirloom extension and
currently unsupported.
- pl
[[+|-]height]
- Change page length. Currently ignored.
- pm
- Print names and sizes of macros, strings, and diversions to standard error
output. Currently ignored.
- pn
[+|-]number
- Change the page number of the next page. Currently ignored.
- pnr
- Print all number registers on standard error output. Currently
ignored.
- po
[[+|-]offset]
- Set a horizontal page offset. If no argument is specified, the page offset
is reverted to its previous value. If a sign is specified, the new page
offset is calculated relative to the current one; otherwise, it is
absolute. The argument follows the syntax of Scaling Widths and the
default scaling unit is m.
- ps
[[+|-]size]
- Change point size. Currently ignored.
- psbb
filename
- Retrieve the bounding box of a PostScript file. Currently
unsupported.
- pshape indent
length ...
- Set a special shape for the current paragraph. This is a Heirloom
extension and currently unsupported.
- pso
command
- Include output of a shell command. Ignored because insecure.
- ptr
- Print the names and positions of all traps on standard error output. This
is a groff extension and currently ignored.
- pvs
[[+|-]height]
- Change post-vertical spacing. This is a groff extension and currently
ignored.
- rchar glyph
...
- Remove glyph definitions. Currently unsupported.
- rd [prompt
[argument ...]]
- Read from standard input. Currently ignored.
- recursionlimit
maxrec maxtail
- Set the maximum stack depth for recursive macros. This is a Heirloom
extension and currently ignored.
- return
[twice]
- Exit the presently executed macro and return to the caller. The argument
is currently ignored.
- rfschar font
glyph ...
- Remove font-specific fallback glyph definitions. Currently
unsupported.
- rhang font char
... afmunits
- Hang characters at right margin. This is a Heirloom extension and
currently ignored.
- rj [N]
- Justify the next N input lines to the right margin without filling.
N defaults to 1. An argument of 0 or less ends right
adjustment.
- rm
macroname
- Remove a request, macro or string.
- rn oldname
newname
- Rename a request, macro, diversion, or string. In mandoc(1), user-defined
macros, mdoc(7) and man(7) macros, and user-defined strings can be
renamed, but renaming of predefined strings and of roff requests is
not supported, and diversions are not implemented at all.
- rnn oldname
newname
- Rename a number register. Currently unsupported.
- rr register
- Remove a register.
- rs
- End no-space mode. Currently ignored.
- rt [dist]
- Return to marked vertical position. Currently ignored.
- schar glyph
[string]
- Define global fallback glyph. This is a groff extension and currently
unsupported.
- sentchar
char ...
- Define sentence-ending characters. This is a Heirloom extension and
currently ignored.
- shc
[glyph]
- Change the soft hyphen character. Currently ignored.
- shift
[number]
- Shift macro arguments number times, by default once: \\$i becomes
what \\$i+number was. Also decrement \n(.$ by number.
- sizes size
...
- Define permissible point sizes. This is a groff extension and currently
ignored.
- so filename
- Include a source file. The file is read and its contents processed as
input in place of the so request line. To avoid inadvertent
inclusion of unrelated files, mandoc(1) only accepts relative paths not
containing the strings "../" and "/..".
This request requires man(1) to change to the right directory
before calling mandoc(1), per convention to the root of the manual tree.
Typical usage looks like:
.so man3/Xcursor.3
As the whole concept is rather fragile, the use of so is
discouraged. Use ln(1) instead.
- sp [height]
- Break the output line and emit vertical space. The argument follows the
syntax of Scaling Widths and defaults to one blank line (1v).
- spacewidth
[1 | 0]
- Set the space width from the font metrics file. This is a Heirloom
extension and currently ignored.
- special [font
...]
- Define a special font. This is a groff extension and currently
ignored.
- spreadwarn
[width]
- Warn about wide spacing between words. Currently ignored.
- ss wordspace
[sentencespace]
- Set space character size. Currently ignored.
- sty position
style
- Associate style with a font position. This is a groff extension and
currently ignored.
- substring
stringname startpos [endpos]
- Replace a user-defined string with a substring. Currently
unsupported.
- sv [height]
- Save vertical space. Currently ignored.
- sy command
- Execute shell command. Ignored because insecure.
- T&
- Re-start a table layout, retaining the options of the prior table
invocation. See TS.
- ta [width ...
[T width ...]]
- Set tab stops. Each width argument follows the syntax of Scaling
Widths. If prefixed by a plus sign, it is relative to the previous tab
stop. The arguments after the T marker are used repeatedly as often
as needed; for each reuse, they are taken relative to the last previously
established tab stop. When ta is called without arguments, all tab
stops are cleared.
- tc [glyph]
- Change tab repetition character. Currently unsupported.
- TE
- End a table context. See TS.
- ti
[+|-]width
- Break the output line and indent the next output line by width. If
a sign is specified, the temporary indentation is calculated relative to
the current indentation; otherwise, it is absolute. The argument follows
the syntax of Scaling Widths and the default scaling unit is
m.
- tkf font minps width1
maxps width2
- Enable track kerning for a font. Currently ignored.
- tl
'left'center'right'Print a title line.
- Currently unsupported.
- tm string
- Print to standard error output. Currently ignored.
- tm1
string
- Print to standard error output, allowing leading blanks. This is a groff
extension and currently ignored.
- tmc
string
- Print to standard error output without a trailing newline. This is a groff
extension and currently ignored.
- tr glyph glyph
...
- Output character translation. The first glyph in each pair is replaced by
the second one. Character escapes can be used; for example,
tr \(xx\(yy
replaces all invocations of \(xx with \(yy.
- track font minps
width1 maxps width2
- Static letter space tracking. This is a Heirloom extension and currently
ignored.
- transchar
char ...
- Define transparent characters for sentence-ending. This is a Heirloom
extension and currently ignored.
- trf
filename
- Output the contents of a file, disallowing invalid characters. This is a
groff extension and ignored because insecure.
- trimat left top
width height
- Set the TrimBox page parameter for PDF generation. This is a Heirloom
extension and currently ignored.
- trin glyph glyph
...
- Output character translation, ignored by asciify. Currently
unsupported.
- trnt glyph glyph
...
- Output character translation, ignored by \!. Currently unsupported.
- troff
-
Force troff mode. This is a groff extension and currently ignored.
- TS
- Begin a table, which formats input in aligned rows and columns. See tbl(7)
for a description of the tbl language.
- uf font
- Globally set the underline font. Currently ignored.
- ul [N]
- Underline next N input lines. Currently ignored.
- unformat
divname
- Unformat spaces and tabs in a diversion. Currently unsupported.
- unwatch
macroname
- Disable notification for string or macro. This is a Heirloom extension and
currently ignored.
- unwatchn
register
- Disable notification for register. This is a Heirloom extension and
currently ignored.
- vpt [1 |
0]
- Enable or disable vertical position traps. This is a groff extension and
currently ignored.
- vs
[[+|-]height]
- Change vertical spacing. Currently ignored.
- warn
flags
- Set warning level. Currently ignored.
- warnscale
si
- Set the scaling indicator used in warnings. This is a groff extension and
currently ignored.
- watch
macroname
- Notify on change of string or macro. This is a Heirloom extension and
currently ignored.
- watchlength
maxlength
- On change, report the contents of macros and strings up to the specified
length. This is a Heirloom extension and currently ignored.
- watchn
register
- Notify on change of register. This is a Heirloom extension and currently
ignored.
- wh dist
[macroname]
- Set a page location trap. Currently unsupported.
- while condition
body
- Repeated execution while a condition is true, with syntax similar
to if. Currently implemented with two restrictions: cannot nest,
and each loop must start and end in the same scope.
- write
["]string
- Write to an open file. Ignored because insecure.
- writec
["]string
- Write to an open file without appending a newline. Ignored because
insecure.
- writem
macroname
- Write macro or string to an open file. Ignored because insecure.
- xflag
level
- Set the extension level. This is a Heirloom extension and currently
ignored.
The nr, if, and ie requests accept integer
numerical expressions as arguments. These are always evaluated using the C
int type; integer overflow works the same way as in the C language.
Numbers consist of an arbitrary number of digits ‘0’ to
‘9’ prefixed by an optional sign ‘+’ or
‘-’. Each number may be followed by one optional scaling unit
described below Scaling Widths. The following equations hold:
1i = 6v = 6P = 10m = 10n = 72p = 1000M = 240u = 240
254c = 100i = 24000u = 24000
1f = 65536u = 65536
The following binary operators are implemented. Unless otherwise
stated, they behave as in the C language:
- +
- addition
- -
- subtraction
- *
- multiplication
- /
- division
- %
- remainder of division
- <
- less than
- >
- greater than
- ==
- equal to
- =
- equal to, same effect as == (this differs from C)
- <=
- less than or equal to
- >=
- greater than or equal to
- <>
- not equal to (corresponds to C !=; this one is of limited
portability, it is supported by Heirloom roff, but not by groff)
- &
- logical and (corresponds to C &&)
- :
-
logical or (corresponds to C ||)
- <?
- minimum (not available in C)
- >?
- maximum (not available in C)
There is no concept of precedence; evaluation proceeds from left
to right, except when subexpressions are enclosed in parentheses. Inside
parentheses, whitespace is ignored.
The mandoc(1) roff parser recognises the following escape
sequences. In mdoc(7) and man(7) documents, using escape sequences is
discouraged except for those described in the LANGUAGE SYNTAX section
above.
A backslash followed by any character not listed here simply
prints that character itself.
- \<newline>
- A backslash at the end of an input line can be used to continue the
logical input line on the next physical input line, joining the text on
both lines together as if it were on a single input line.
- \<space>
- The escape sequence backslash-space (‘\ ’) is an
unpaddable space-sized non-breaking space character; see Whitespace
and mandoc_char(7).
- \!
- Embed text up to and including the end of the input line into the current
diversion or into intermediate output without interpreting requests,
macros, and escapes. Currently unsupported.
- \"
- The rest of the input line is treated as Comments.
- \#
- Line continuation with comment. Discard the rest of the physical input
line and continue the logical input line on the next physical input line,
joining the text on both lines together as if it were on a single input
line. This is a groff extension.
- \$arg
- Macro argument expansion, see de.
- \%
- Hyphenation allowed at this point of the word; ignored by mandoc(1).
- \&
- Non-printing zero-width character, often used for various kinds of
escaping; see Whitespace, mandoc_char(7), and the “MACRO
SYNTAX” and “Delimiters” sections in mdoc(7).
- \'
- Acute accent special character; use \(aa instead.
- \(cc
- Special Characters with two-letter names, see mandoc_char(7).
- \)
- Zero-width space transparent to end-of-sentence detection; ignored by
mandoc(1).
- \*[name]
- Interpolate the string with the name. For short names, there are
variants \*c and \*(cc.
One string is predefined on the roff language level:
\*(.T expands to the name of the output device, for example
ascii, utf8, ps, pdf, html, or markdown.
Macro sets traditionally predefine additional strings which
are not portable and differ across implementations. Those supported by
mandoc(1) are listed in mandoc_char(7).
Strings can be defined, changed, and deleted with the
ds, as, and rm requests.
- \,
- Left italic correction (groff extension); ignored by mandoc(1).
- \-
- Special character “mathematical minus sign”; see
mandoc_char(7) for details.
- \/
- Right italic correction (groff extension); ignored by mandoc(1).
- \:
- Breaking the line is allowed at this point of the word without inserting a
hyphen.
- \?
- Embed the text up to the next \? into the current diversion without
interpreting requests, macros, and escapes. This is a groff extension and
currently unsupported.
- \[name]
- Special Characters with names of arbitrary length, see
mandoc_char(7).
- \^
- One-twelfth em half-narrow space character, effectively zero-width in
mandoc(1).
- \_
- Underline special character; use \(ul instead.
- \`
- Grave accent special character; use \(ga instead.
- \{
- Begin conditional input; see if.
- \|
- One-sixth em narrow space character, effectively zero-width in
mandoc(1).
- \}
- End conditional input; see if.
- \~
- Paddable non-breaking space character.
- \0
- Digit width space character.
- \A'string'
- Anchor definition; ignored by mandoc(1).
- \a
- Leader character; ignored by mandoc(1).
- \B'string'
- Interpolate ‘1’ if string conforms to the syntax of
Numerical expressions explained above or ‘0’
otherwise.
- \b'string'
- Bracket building function; ignored by mandoc(1).
- \C'name'
- Special Characters with names of arbitrary length.
- \c
- When encountered at the end of an input text line, the next input text
line is considered to continue that line, even if there are request or
macro lines in between. No whitespace is inserted.
- \D'string'
- Draw graphics function; ignored by mandoc(1).
- \d
- Move down by half a line; ignored by mandoc(1).
- \E
- Escape character intended to not be interpreted in copy mode. In
mandoc(1), it currently does the same as \ itself.
- \e
- Backslash special character.
- \F[name]
- Switch font family (groff extension); ignored by mandoc(1). For short
names, there are variants \Fc and \F(cc.
- \f[name]
- Switch to the font name, see Font Selection. For short
names, there are variants \fc and \f(cc. An
empty name \f[] defaults to \fP.
- \g[name]
- Interpolate the format of a number register; ignored by mandoc(1). For
short names, there are variants \gc and
\g(cc.
- \H'[+|-]number'
- Set the height of the current font; ignored by mandoc(1).
- \h'[|]width'
- Horizontal motion. If the vertical bar is given, the motion is relative to
the current indentation. Otherwise, it is relative to the current
position. The default scaling unit is m.
- \k[name]
- Mark horizontal input place in register; ignored by mandoc(1). For short
names, there are variants \kc and \k(cc.
- \L'number[c]'
- Vertical line drawing function; ignored by mandoc(1).
- \l'width[c]'
- Draw a horizontal line of width using the glyph c.
- \M[name]
- Set fill (background) color (groff extension); ignored by mandoc(1). For
short names, there are variants \Mc and
\M(cc.
- \m[name]
- Set glyph drawing color (groff extension); ignored by mandoc(1). For short
names, there are variants \mc and \m(cc.
- \N'number'
- Character number on the current font.
- \n[+|-][name]
- Interpolate the number register name. For short names, there are
variants \nc and \n(cc. If the optional sign
is specified, the register is first incremented or decremented by the
stepsize that was specified in the relevant nr request, and
the changed value is interpolated.
- \Odigit,
\O[5arguments]
- Suppress output. This is a groff extension and currently unsupported. With
an argument of 1, 2, 3, or 4, it is
ignored.
- \o'string'
- Overstrike, writing all the characters contained in the string to
the same output position. In terminal and HTML output modes, only the last
one of the characters is visible.
- \p
- Break the output line at the end of the current word.
- \R'name
[+|-]number'
- Set number register; ignored by mandoc(1).
- \r
- Move up by one line; ignored by mandoc(1).
- \S'number'
- Slant output; ignored by mandoc(1).
- \s'[+|-]number'
- Change point size; ignored by mandoc(1). Alternative forms
\s[+|-]n, \s[+|-]'number',
\s[[+|-]number], and
\s[+|-][number] are also parsed and
ignored.
- \t
- Horizontal tab; ignored by mandoc(1).
- \u
- Move up by half a line; ignored by mandoc(1).
- \V[name]
- Interpolate an environment variable; ignored by mandoc(1). For short
names, there are variants \Vc and \V(cc.
- \v'number'
- Vertical motion; ignored by mandoc(1).
- \w'string'
- Interpolate the width of the string. The mandoc(1) implementation
assumes that after expansion of user-defined strings, the string
only contains normal characters, no escape sequences, and that each
character has a width of 24 basic units.
- \X'string'
- Output string as device control function; ignored in nroff mode and
by mandoc(1).
- \x'number'
- Extra line space function; ignored by mandoc(1).
- \Y[name]
- Output a string as a device control function; ignored in nroff mode and by
mandoc(1). For short names, there are variants \Yc and
\Y(cc.
- \Z'string'
- Print string with zero width and height; ignored by mandoc(1).
- \z
- Output the next character without advancing the cursor position.
The mandoc(1) implementation of the roff language is
incomplete. Major unimplemented features include:
- -
- For security reasons, mandoc(1) never reads or writes external files
except via so requests with safe relative paths.
- -
- There is no automatic hyphenation, no adjustment to the right margin, and
very limited support for centering; the output is always set
flush-left.
- -
- Support for setting tabulator and leader characters is missing, and
support for manually changing indentation is limited.
- -
- The ‘u’ scaling unit is the default terminal unit. In
traditional troff systems, this unit changes depending on the output
media.
- -
- Width measurements are implemented in a crude way and often yield wrong
results. Support for explicit movement requests and escapes is
limited.
- -
- There is no concept of output pages, no support for floats, graphics
drawing, and picture inclusion; terminal output is always continuous.
- -
- Requests regarding color, font families, font sizes, and glyph
manipulation are ignored. Font support is very limited. Kerning is not
implemented, and no ligatures are produced.
- -
- The "'" macro control character does not suppress output line
breaks.
- -
- Diversions and environments are not implemented, and support for traps is
very incomplete.
- -
- Use of macros is not supported inside tbl(7) code.
The special semantics of the nS number register is an
idiosyncrasy of OpenBSD manuals and not supported by other mdoc(7)
implementations.
mandoc(1), eqn(7), man(7), mandoc_char(7), mdoc(7), tbl(7)
Joseph F. Ossanna and Brian W. Kernighan, Troff User's
Manual, AT&T Bell Laboratories, Computing Science Technical
Report, 54, http://www.kohala.com/start/troff/cstr54.ps, Murray Hill, New
Jersey, 1976 and 1992.
Joseph F. Ossanna, Brian W. Kernighan, and Gunnar Ritter,
Heirloom Documentation Tools Nroff/Troff User's Manual,
http://heirloom.sourceforge.net/doctools/troff.pdf, September 17, 2007.
The RUNOFF typesetting system, whose input forms the basis for
roff, was written in MAD and FAP for the CTSS operating system by
Jerome E. Saltzer in 1964. Doug McIlroy rewrote it in BCPL in 1969, renaming
it roff. Dennis M. Ritchie rewrote McIlroy's roff in PDP-11
assembly for Version 1 AT&T UNIX, Joseph F. Ossanna improved roff
and renamed it nroff for Version 2 AT&T UNIX, then ported nroff
to C as troff, which Brian W. Kernighan released with Version 7
AT&T UNIX. In 1989, James Clark re-implemented troff in C++, naming it
groff.
This roff reference was written by Kristaps Dzonsons
<kristaps@bsd.lv> and Ingo Schwarze
<schwarze@openbsd.org>.