MANDOC_CHAR(7) Standards, Environments, and Macros MANDOC_CHAR(7)

NAME

mandoc_char - mandoc special characters

DESCRIPTION

This page documents the mandoc_roff(7) escape sequences accepted by
mandoc(1) to represent special characters in mdoc(7) and man(7)
documents.

The rendering depends on the mandoc(1) output mode; it can be inspected
by calling man(1) on the mandoc_char manual page with different -T
arguments. In ASCII output, the rendering of some characters may be
hard to interpret for the reader. Many are rendered as descriptive
strings like "<integral>", "<degree>", or "<Gamma>", which may look
ugly, and many are replaced by similar ASCII characters. In
particular, accented characters are usually shown without the accent.
For that reason, try to avoid using any of the special characters
documented here except those discussed in the DESCRIPTION, unless they
are essential for explaining the subject matter at hand, for example
when documenting complicated mathematical functions.

In particular, in English manual pages, do not use special-character
escape sequences to represent national language characters in author
names; instead, provide ASCII transcriptions of the names.

Dashes and Hyphens

In typography there are different types of dashes of various width: the
hyphen (-), the en-dash (-), the em-dash (--), and the mathematical
minus sign (-).

Hyphens are used for adjectives; to separate the two parts of a
compound word; or to separate a word across two successive lines of
text. The hyphen does not need to be escaped:

blue-eyed
lorry-driver

The en-dash is used to separate the two elements of a range, or can be
used the same way as an em-dash. It should be written as `\(en':

pp. 95\(en97.
Go away \(en or else!

The em-dash can be used to show an interruption or can be used the same
way as colons, semi-colons, or parentheses. It should be written as
`\(em':

Three things \(em apples, oranges, and bananas.
This is not that \(em rather, this is that.

In mandoc_roff(7) documents, the minus sign is normally written as
`\-'. In manual pages, some style guides recommend to also use `\-' if
an ASCII 0x2d "hyphen-minus" output glyph that can be copied and pasted
is desired in output modes supporting it, for example in -T utf8 and -T
html. But currently, no practically relevant manual page formatter
requires that subtlety, so in manual pages, it is sufficient to write
plain `-' to represent hyphen, minus, and hyphen-minus.

If a word on a text input line contains a hyphen, a formatter may
decide to insert an output line break after the hyphen if that helps
filling the current output line, but the whole word would overflow the
line. If it is important that the word is not broken across lines in
this way, a zero-width space (`\&') can be inserted before or after the
hyphen. While mandoc(1) never breaks the output line after hyphens
adjacent to a zero-width space, after any of the other dash- or hyphen-
like characters represented by escape sequences, or after hyphens
inside words in macro arguments, other software may not respect these
rules and may break the line even in such cases.

Some mandoc_roff(7) implementations contains dictionaries allowing to
break the line at syllable boundaries even inside words that contain no
hyphens. Such automatic hyphenation is not supported by mandoc(1),
which only breaks the line at whitespace, and inside words only after
existing hyphens.

Spaces

To separate words in normal text, for indenting and alignment in
literal context, and when none of the following special cases apply,
just use the normal space character (` ').

When filling text, output lines may be broken between words, i.e. at
space characters. To prevent a line break between two particular
words, use the unpaddable non-breaking space escape sequence (`\ ')
instead of the normal space character. For example, the input string
"number\ 1" will be kept together as "number 1" on the same output
line.

On request and macro lines, the normal space character serves as an
argument delimiter. To include whitespace into arguments, quoting is
usually the best choice; see the MACRO SYNTAX section in
mandoc_roff(7). In some cases, using the non-breaking space escape
sequence (`\ ') may be preferable.

To escape macro names and to protect whitespace at the end of input
lines, the zero-width space (`\&') is often useful. For example, in
mdoc(7), a normal space character can be displayed in single quotes in
either of the following ways:

.Sq " "
.Sq \ \&

Quotes

On request and macro lines, the double-quote character (`"') is handled
specially to allow quoting. One way to prevent this special handling
is by using the `\(dq' escape sequence.

Note that on text lines, literal double-quote characters can be used
verbatim. All other quote-like characters can be used verbatim as
well, even on request and macro lines.

Accents

In output modes supporting such special output characters, for example
-T pdf, and sometimes less consistently in -T utf8, some mandoc_roff(7)
formatters convert the following ASCII input characters to the
following Unicode special output characters:

` U+2018 left single quotation mark
' U+2019 right single quotation mark
~ U+02DC small tilde
^ U+02C6 modifier letter circumflex

In prose, this automatic substitution is often desirable; but when
these characters have to be displayed as plain ASCII characters, for
example in source code samples, they require escaping to render as
follows:

\(ga U+0060 grave accent
\(aq U+0027 apostrophe
\(ti U+007E tilde
\(ha U+005E circumflex accent

Periods

The period (`.') is handled specially at the beginning of an input
line, where it introduces a mandoc_roff(7) request or a macro, and when
appearing alone as a macro argument in mdoc(7). In such situations,
prepend a zero-width space (`\&.') to make it behave like normal text.

Do not use the `\.' escape sequence. It does not prevent special
handling of the period.

Backslashes

To include a literal backslash (`\') into the output, use the (`\e')
escape sequence.

Note that doubling it (`\\') is not the right way to output a
backslash. Because mandoc(1) does not implement full mandoc_roff(7)
functionality, it may work with mandoc(1), but it may have weird
effects on complete mandoc_roff(7) implementations.

SPECIAL CHARACTERS

Special characters are encoded as `\X' (for a one-character escape),
`\(XX' (two-character), and `\[N]' (N-character). For details, see the
Special Characters subsection of the mandoc_roff(7) manual.

Spaces, non-breaking unless stated otherwise:
Input Description
`\ ' unpaddable space
\~ paddable space
\0 digit-width space
\| one-sixth \(em narrow space, zero width in nroff mode
\^ one-twelfth \(em half-narrow space, zero width in nroff
\& zero-width space
\) zero-width space transparent to end-of-sentence
detection
\% zero-width space allowing hyphenation
\: zero-width space allowing line break

Lines:
Input Rendered Description
\(ba | bar
\(br | box rule
\(ul _ underscore
\(ru _ underscore (width 0.5m)
\(rn - overline
\(bb | broken bar
\(sl / forward slash
\(rs \ backward slash

Text markers:
Input Rendered Description
\(ci O circle
\(bu +o bullet
\(dd <**> double dagger
\(dg <*> dagger
\(lz <> lozenge
\(sq [] white square
\(ps <paragraph> paragraph
\(sc <section> section
\(lh <= left hand
\(rh => right hand
\(at @ at
\(sh # hash (pound)
\(CR <cr> carriage return
\(OK \/ check mark
\(CL C club suit
\(SP S spade suit
\(HE H heart suit
\(DI D diamond suit

Legal symbols:
Input Rendered Description
\(co (C) copyright
\(rg (R) registered
\(tm tm trademarked

Punctuation:
Input Rendered Description
\(em -- em-dash
\(en - en-dash
\(hy - hyphen
\e \ back-slash
\. . period
\(r! ! upside-down exclamation
\(r? ? upside-down question

Quotes:
Input Rendered Description
\(Bq ,, right low double-quote
\(bq , right low single-quote
\(lq " left double-quote
\(rq " right double-quote
\(oq ` left single-quote
\(cq ' right single-quote
\(aq ' apostrophe quote (ASCII character)
\(dq " double quote (ASCII character)
\(Fo << left guillemet
\(Fc >> right guillemet
\(fo < left single guillemet
\(fc > right single guillemet

Brackets:
Input Rendered Description
\(lB [ left bracket
\(rB ] right bracket
\(lC { left brace
\(rC } right brace
\(la < left angle
\(ra > right angle
\(bv | brace extension (special font)
\[braceex] | brace extension
\[bracketlefttp] | top-left hooked bracket
\[bracketleftbt] | bottom-left hooked bracket
\[bracketleftex] | left hooked bracket extension
\[bracketrighttp] | top-right hooked bracket
\[bracketrightbt] | bottom-right hooked bracket
\[bracketrightex] | right hooked bracket extension
\(lt ,- top-left hooked brace
\[bracelefttp] ,- top-left hooked brace
\(lk { mid-left hooked brace
\[braceleftmid] { mid-left hooked brace
\(lb `- bottom-left hooked brace
\[braceleftbt] `- bottom-left hooked brace
\[braceleftex] | left hooked brace extension
\(rt -. top-left hooked brace
\[bracerighttp] -. top-right hooked brace
\(rk } mid-right hooked brace
\[bracerightmid] } mid-right hooked brace
\(rb -' bottom-right hooked brace
\[bracerightbt] -' bottom-right hooked brace
\[bracerightex] | right hooked brace extension
\[parenlefttp] / top-left hooked parenthesis
\[parenleftbt] \ bottom-left hooked parenthesis
\[parenleftex] | left hooked parenthesis
extension
\[parenrighttp] \ top-right hooked parenthesis
\[parenrightbt] / bottom-right hooked parenthesis
\[parenrightex] | right hooked parenthesis
extension

Arrows:
Input Rendered Description
\(<- <- left arrow
\(-> -> right arrow
\(<> <-> left-right arrow
\(da |v down arrow
\(ua |^ up arrow
\(va ^v up-down arrow
\(lA <= left double-arrow
\(rA => right double-arrow
\(hA <=> left-right double-arrow
\(uA =^ up double-arrow
\(dA =v down double-arrow
\(vA ^=v up-down double-arrow
\(an - horizontal arrow extension

Logical:
Input Rendered Description
\(AN ^ logical and
\(OR v logical or
\[tno] ~ logical not (text font)
\(no ~ logical not (special font)
\(te <there exists>
existential quantifier
\(fa <for all> universal quantifier
\(st <such that> such that
\(tf <therefore> therefore
\(3d <therefore> therefore
\(or | bitwise or

Mathematical:
Input Rendered Description
\- - minus (text font)
\(mi - minus (special font)
+ + plus (text font)
\(pl + plus (special font)
\(-+ -+ minus-plus
\[t+-] +- plus-minus (text font)
\(+- +- plus-minus (special font)
\(pc . center-dot
\[tmu] x multiply (text font)
\(mu x multiply (special font)
\(c* Ox circle-multiply
\(c+ O+ circle-plus
\[tdi] / divide (text font)
\(di / divide (special font)
\(f/ / fraction
\(** * asterisk
\(<= <= less-than-equal
\(>= >= greater-than-equal
\(<< << much less
\(>> >> much greater
\(eq = equal
\(!= != not equal
\(== == equivalent
\(ne !== not equivalent
\(ap ~ tilde operator
\(|= -~ asymptotically equal
\(=~ =~ approximately equal
\(~~ ~~ almost equal
\(~= ~= almost equal
\(pt <proportional to>
proportionate
\(es {} empty set
\(mo <element of>
element
\(nm <not element of>
not element
\(sb <proper subset>
proper subset
\(nb <not subset>
not subset
\(sp <proper superset>
proper superset
\(nc <not superset>
not superset
\(ib <subset or equal>
reflexive subset
\(ip <superset or equal>
reflexive superset
\(ca <intersection>
intersection
\(cu <union> union
\(/_ <angle> angle
\(pp <perpendicular>
perpendicular
\(is <integral> integral
\[integral] <integral> integral
\[sum] <sum> summation
\[product] <product> product
\[coproduct] <coproduct> coproduct
\(gr <nabla> gradient
\(sr <sqrt> square root
\[sqrt] <sqrt> square root
\(lc |~ left-ceiling
\(rc ~| right-ceiling
\(lf |_ left-floor
\(rf _| right-floor
\(if <infinity> infinity
\(Ah <Aleph> aleph
\(Im <Im> imaginary
\(Re <Re> real
\(wp p Weierstrass p
\(pd <del> partial differential
\(-h /h Planck constant over 2<pi>
\[hbar] /h Planck constant over 2<pi>
\(12 1/2 one-half
\(14 1/4 one-fourth
\(34 3/4 three-fourths
\(18 1/8 one-eighth
\(38 3/8 three-eighths
\(58 5/8 five-eighths
\(78 7/8 seven-eighths
\(S1 ^1 superscript 1
\(S2 ^2 superscript 2
\(S3 ^3 superscript 3

Ligatures:
Input Rendered Description
\(ff ff ff ligature
\(fi fi fi ligature
\(fl fl fl ligature
\(Fi ffi ffi ligature
\(Fl ffl ffl ligature
\(AE AE AE
\(ae ae ae
\(OE OE OE
\(oe oe oe
\(ss ss German eszett
\(IJ IJ IJ ligature
\(ij ij ij ligature

Accents:
Input Rendered Description
\(a" " Hungarian umlaut
\(a- - macron
\(a. . dotted
\(a^ ^ circumflex
\(aa ' acute
\' ' acute
\(ga ` grave
\` ` grave
\(ab '` breve
\(ac , cedilla
\(ad " dieresis
\(ah v caron
\(ao o ring
\(a~ ~ tilde
\(ho , ogonek
\(ha ^ hat (ASCII character)
\(ti ~ tilde (ASCII character)

Accented letters:
Input Rendered Description
\('A 'A acute A
\('E 'E acute E
\('I 'I acute I
\('O 'O acute O
\('U 'U acute U
\('Y 'Y acute Y
\('a 'a acute a
\('e 'e acute e
\('i 'i acute i
\('o 'o acute o
\('u 'u acute u
\('y 'y acute y
\(`A `A grave A
\(`E `E grave E
\(`I `I grave I
\(`O `O grave O
\(`U `U grave U
\(`a `a grave a
\(`e `e grave e
\(`i `i grave i
\(`o `i grave o
\(`u `u grave u
\(~A ~A tilde A
\(~N ~N tilde N
\(~O ~O tilde O
\(~a ~a tilde a
\(~n ~n tilde n
\(~o ~o tilde o
\(:A "A dieresis A
\(:E "E dieresis E
\(:I "I dieresis I
\(:O "O dieresis O
\(:U "U dieresis U
\(:a "a dieresis a
\(:e "e dieresis e
\(:i "i dieresis i
\(:o "o dieresis o
\(:u "u dieresis u
\(:y "y dieresis y
\(^A ^A circumflex A
\(^E ^E circumflex E
\(^I ^I circumflex I
\(^O ^O circumflex O
\(^U ^U circumflex U
\(^a ^a circumflex a
\(^e ^e circumflex e
\(^i ^i circumflex i
\(^o ^o circumflex o
\(^u ^u circumflex u
\(,C ,C cedilla C
\(,c ,c cedilla c
\(/L /L stroke L
\(/l /l stroke l
\(/O /O stroke O
\(/o /o stroke o
\(oA oA ring A
\(oa oa ring a

Special letters:
Input Rendered Description
\(-D Dh Eth
\(Sd dh eth
\(TP Th Thorn
\(Tp th thorn
\(.i i dotless i
\(.j j dotless j

Currency:
Input Rendered Description
\(Do $ dollar
\(ct /c cent
\(Eu EUR Euro symbol
\(eu EUR Euro symbol
\(Ye =Y yen
\(Po -L pound
\(Cs ox Scandinavian
\(Fn ,f florin

Units:
Input Rendered Description
\(de <degree> degree
\(%0 <permille> per-thousand
\(fm ' minute
\(sd '' second
\(mc <micro> micro
\(Of a Spanish female ordinal
\(Om o Spanish masculine ordinal

Greek letters:
Input Rendered Description
\(*A A Alpha
\(*B B Beta
\(*G <Gamma> Gamma
\(*D <Delta> Delta
\(*E E Epsilon
\(*Z Z Zeta
\(*Y H Eta
\(*H <Theta> Theta
\(*I I Iota
\(*K K Kappa
\(*L <Lambda> Lambda
\(*M M Mu
\(*N N Nu
\(*C <Xi> Xi
\(*O O Omicron
\(*P <Pi> Pi
\(*R P Rho
\(*S <Sigma> Sigma
\(*T T Tau
\(*U Y Upsilon
\(*F <Phi> Phi
\(*X X Chi
\(*Q <Psi> Psi
\(*W <Omega> Omega
\(*a <alpha> alpha
\(*b <beta> beta
\(*g <gamma> gamma
\(*d <delta> delta
\(*e <epsilon> epsilon
\(*z <zeta> zeta
\(*y <eta> eta
\(*h <theta> theta
\(*i <iota> iota
\(*k <kappa> kappa
\(*l <lambda> lambda
\(*m <mu> mu
\(*n <nu> nu
\(*c <xi> xi
\(*o o omicron
\(*p <pi> pi
\(*r <rho> rho
\(*s <sigma> sigma
\(*t <tau> tau
\(*u <upsilon> upsilon
\(*f <phi> phi
\(*x <chi> chi
\(*q <psi> psi
\(*w <omega> omega
\(+h <theta> theta variant
\(+f <phi> phi variant
\(+p <pi> pi variant
\(+e <epsilon> epsilon variant
\(ts <sigma> sigma terminal

PREDEFINED STRINGS

Predefined strings are inherited from the macro packages of historical
troff implementations. They are not recommended for use, as they
differ across implementations. Manuals using these predefined strings
are almost certainly not portable.

Their syntax is similar to special characters, using `\*X' (for a
one-character escape), `\*(XX' (two-character), and `\*[N]'
(N-character).

Input Rendered Description
\*(Ba | vertical bar
\*(Ne != not equal
\*(Ge >= greater-than-equal
\*(Le <= less-than-equal
\*(Gt > greater-than
\*(Lt < less-than
\*(Pm +- plus-minus
\*(If infinity infinity
\*(Pi pi pi
\*(Na NaN NaN
\*(Am & ampersand
\*R (R) restricted mark
\*(Tm (Tm) trade mark
\*q " double-quote
\*(Rq " right-double-quote
\*(Lq " left-double-quote
\*(lp ( right-parenthesis
\*(rp ) left-parenthesis
\*(lq " left double-quote
\*(rq " right double-quote
\*(ua |^ up arrow
\*(va ^v up-down arrow
\*(<= <= less-than-equal
\*(>= >= greater-than-equal
\*(aa ' acute
\*(ga ` grave
\*(Px POSIX POSIX standard name
\*(Ai ANSI ANSI standard name

UNICODE CHARACTERS

The escape sequences

\[uXXXX] and \C'uXXXX'

are interpreted as Unicode codepoints. The codepoint must be in the
range above U+0080 and less than U+10FFFF. For compatibility, the
hexadecimal digits `A' to `F' must be given as uppercase characters,
and points must be zero-padded to four characters; if greater than four
characters, no zero padding is allowed. Unicode surrogates are not
allowed.

NUMBERED CHARACTERS

For backward compatibility with existing manuals, mandoc(1) also
supports the

\N'number' and \[charnumber]

escape sequences, inserting the character number from the current
character set into the output. Of course, this is inherently non-
portable and is already marked as deprecated in the Heirloom roff
manual; on top of that, the second form is a GNU extension. For
example, do not use \N'34' or \[char34], use \(dq, or even the plain
`"' character where possible.

COMPATIBILITY

This section documents compatibility between mandoc and other troff
implementations, at this time limited to GNU troff ("groff").

- The \N'' escape sequence is limited to printable characters; in
groff, it accepts arbitrary character numbers.
- In -Tascii, the \(ss, \(nm, \(nb, \(nc, \(ib, \(ip, \(pp, \[sum],
\[product], \[coproduct], \(gr, \(-h, and \(a. special characters
render differently between mandoc and groff.
- In -Thtml, the \(~=, \(nb, and \(nc special characters render
differently between mandoc and groff.
- The -Tps and -Tpdf modes format like -Tascii instead of rendering
glyphs as in groff.
- The \[radicalex], \[sqrtex], and \(ru special characters have been
omitted from mandoc either because they are poorly documented or
they have no known representation.

SEE ALSO

mandoc(1), man(7), mandoc_roff(7), mdoc(7)

AUTHORS

The mandoc_char manual page was written by Kristaps Dzonsons
<kristaps@bsd.lv>.

CAVEATS

The predefined string `\*(Ba' mimics the behaviour of the `|' character
in mdoc(7); thus, if you wish to render a vertical bar with no side
effects, use the `\(ba' escape.

illumos October 31, 2020 illumos